SSLA, 26, 1–34+ Printed in the United States of America+

DOI: 10+10170S0272263104261010

PERCEIVING VOWELS IN A
SECOND LANGUAGE

James Emil Flege

University of Alabama

Ian R+ A+ MacKay
University of Ottawa

This study examines the perception of English vowels by native speak-

ers of Italian. In two preliminary experiments, Italian university stu-
dents who had lived in Canada for 3 months were found to have
difficulty discriminating /Á/-/ö/, /E/-/æ/, and /i/-/I/ because they often
identified both members of each contrast as instances of a single
Italian vowel. The participants in two other experiments, long-time
residents of Canada, were assigned to groups based on their age of
arrival in Canada from Italy (early vs. late) and percentage of first
language (L1) use (high L1 use vs. low L1 use). Experiment 3 focused
on the discrimination of /Á/-/ö/, /E/-/æ/, and /i/-/I/, and experiment 4
examined the discrimination of correct from incorrect realizations of
/I/ and /i/. In both experiments, the early learners obtained higher
discrimination scores than the late learners, and low-L1-use partici-
pants obtained higher scores than high-L1-use participants. Most
important, the early learners who used Italian often (early high),
but not the early learners who used Italian seldom (early low), were
found to differ from native speakers of English in perceiving English
vowels. These results suggest two important conclusions regard-
ing second language (L2) perceptual learning: Learning an L2 in
childhood does not guarantee a nativelike perception of L2 vowels,
nor does the establishment of a sound system for the L1 preclude
a functionally nativelike perception of L2 vowels. Another important

This study was supported by grant DC00257 from the National Institute of Deafness and Other Com-
municative Disorders+ The authors thank J+ Prosperine and M+ Pearse for help locating participants,
Fr+ M+ Brodeur of St+ Anthony’s Church in Ottawa, Ontario, and all the participants+ The authors are
grateful to D+ Meador and T+ Piske for help preparing the stimuli used in experiment 4+ Finally, thanks
are extended to K+ Aoyama, S+ Imai, K+ Tsukada, T+ Piske, and three anonymous SSLA reviewers for
comments on an earlier version of this article+
Address correspondence to: J+ E+ Flege, Division of Speech and Hearing Sciences, CH20, Room
119, 1530 Third Avenue South, Birmingham, AL 35294-2042; e-mail: jeflege@uab+edu+

© 2004 Cambridge University Press 0272-2631004 $12+00 1

2 James Emil Flege and Ian R. A. MacKay

finding is that, although the late learners generally perceived English

vowels less accurately than the early learners, some perceived them
accurately.

It is important to understand how the vowels of a second language ~L2! are

perceived+ Differences in segmental perception between native and nonnative
speakers may slow the processing of an L2 ~Munro & Derwing, 1995; Schmid
& Yeni-Komshian, 1999! and may contribute to word-recognition difficulty ~e+g+,
Bradlow & Pisoni, 1999; Mayo, Florentine, & Buus, 1997!+ It has also been
hypothesized ~e+g+, Rochet, 1995! that native-nonnative differences in percep-
tion may limit the accuracy with which L2 phonetic segments can be pro-
duced+ The aim of this study, therefore, is to provide a better understanding
of L2 vowel perception+ The study focuses on the question as to whether adults
who begin learning their L2 in childhood can or cannot perceive L2 vowels in
a nativelike fashion+
A number of studies have examined the production of L2 vowels by adults
who were first exposed to their L2 either in childhood ~early learners! or in
late adolescence or early adulthood ~late learners!+ These studies have shown
that an influence of the first language ~L1! vowel system is often readily appar-
ent in late learners’ production of L2 vowels, especially in early stages of
learning ~Jun & Cowie, 1994; Major, 1987; Munro, 1993!+ However, late learners
typically produce L2 vowels more accurately as they gain experience in the
L2, sometimes producing L2 vowels with formant frequency values that are
intermediate to the values observed for monolingual speakers of the L1 and
L2 ~e+g+, Flege & Hillenbrand, 1984!+ Experienced late learners have also been
observed to produce certain L2 vowels accurately, especially when the L2 vow-
els are located in a portion of vowel space that is not occupied by an L1 vowel
~Bohn & Flege, 1992; Flege, 1987, 1992b; Ingram & Park, 1997!+ Previous research
has shown that early learners produce L2 vowels more accurately than most
late learners ~Baker, Trofimovich, Mack, & Flege, 2002; Flege, 1992a; Munro,
Flege, & MacKay, 1996! although they may differ from the native speakers of
the target language in producing certain vowels if they continue using their
L1 frequently ~Flege, Schirru, & MacKay, 2003; Piske, Flege, MacKay, & Meador,
2002!+
A similar pattern of results has been obtained in research examining the
perception of L2 vowels+ Gottfried ~1984! found that native speakers of English
who had studied French in the United States correctly identified naturally pro-
duced French vowels less often than native French speakers ~see also Ingram
& Park, 1997!+ The participants in a study by Flege, Bohn, and Jang ~1997!
identified the members of a synthetic “beat-to-bit” ~0i0-to-0I0! continuum that
differed orthogonally in spectral quality and duration+ Native English speak-
ers based their judgments primarily on spectral quality, whereas many of the
native Spanish late learners based their judgments exclusively on vowel dura-
L2 Vowel Perception 3

tion+ The results suggested that some native Spanish late learners failed to
perceive the spectral difference between English 0i0 and 0I0 even though pre-
vious research had shown that native Spanish adults can auditorily detect
such differences ~Flege, 1991; Flege, Munro, & Fox, 1994!+ However, 4 of the 20
late learners who were examined showed a nativelike use of spectral differ-
ences in classifying the English vowels ~see also Morrison, 2002!+
Baker et al+ ~2002! examined the discrimination of English vowels by groups
of Koreans who were matched for years of residence in the United States ~M 5
9 years! but differed in age of arrival ~AOA, M 5 9 vs+ 19 years! and percent-
age Korean use ~M 5 31% vs+ 55%!+ The early learners discriminated English
vowels better than the late learners but did not differ significantly from native
English ~NE! speakers+ Similar results were obtained by Flege, MacKay, and
Meador ~1999!, who examined the discrimination of English vowels by native
speakers of Italian+ The native Italian ~NI! participants were selected based on
their AOA in Canada from Italy and percentage Italian use+ The participants in
groups designated “early high” and “late high” used Italian relatively often but
differed in AOA ~M 5 7 vs+ 19 years!, whereas participants in “early low” and
“early high” groups were matched for AOA but differed in Italian use ~M 5 8%
vs+ 32%!+ Both groups of early learners ~early low and early high! obtained
higher discrimination scores than the late bilinguals but did not differ signif-
icantly from either the NE group or one another+
Other studies have provided evidence that early learners differ from native
speakers of the target L2 ~or L2 native speakers, for short!, however+ Mack
~1989! reported that French-English bilinguals living in the United States iden-
tified significantly fewer members of a synthetic 0i0-0I0 continuum as 0i0 than
NE speakers+ Four studies tested for differences between native Spanish learn-
ers of Catalan and native speakers of Catalan+ The early learners in these stud-
ies were university students in Barcelona who had begun to learn Catalan by
school age, were highly proficient in both Spanish and Catalan, and were said
to use both languages frequently+ Each study used a different technique to
assess the perception of Catalan speech sounds+ Pallier, Bosch, and Sebastián-
Gallés ~1997! examined the identification and discrimination of vowels in a
synthetic continuum+ Pallier, Colomé, and Sebastián-Gallés ~2001! used the rep-
etition priming paradigm+ Sebastián-Gallés and Soto-Faraco ~1999! used a ver-
sion of the gating paradigm+ Bosch, Costa, and Sebastián-Gallés ~2000! employed
the “perceptual magnet” paradigm+ All four studies examined Catalan 0e0 and
0E0, and all four revealed differences between early learners and native speak-
ers in the perception of these vowels+1 For example, the grouped 0e0-0E0 iden-
tification function obtained by Pallier et al+ ~1997! for native speakers of Catalan
but not for early learners revealed a clear crossover from 0e0 to 0E0+
The results obtained for early learners in Barcelona suggested that an accu-
rate perception of L2 vowels might be impossible following establishment of
the L1 sound system+ Sebastián-Gallés and Soto-Faraco ~1999, p+ 120! inter-
preted their findings to indicate a “lack of plasticity” in early learners and
suggested that the malleability of the speech perception system might be lim-
4 James Emil Flege and Ian R. A. MacKay

ited “severely” by school age because exposure to the L1 exerts a “very strong
constraint” on the “organization and acquisition of phonemic categories+” Pal-
lier et al+ ~1997, p+ B14! concluded that even early and frequent exposure to
an L2 might be insufficient to permit the learning of “two new phonetic cat-
egories which overlap” a single L1 category+ Bosch et al+ ~2000, pp+ 215–216!
inferred that the early learners continued to represent Catalan vowels as “for-
eign” speech sounds for which “stable representations in long-term memory”
were not established+

CAN EARLY LEARNERS PERCEIVE L2 VOWELS ACCURATELY?

The basis for vowel perception differences between the early learners in Bar-
celona and L2 native speakers is uncertain+ The differences were probably
not due to the passing of a critical period, at least not one ending at the age
of 12 years ~Scovel, 1988, 2000! or 15 years ~Patkowski, 1989!+ It seems unlikely
that a critical period for L2 speech perception, should one exist, would occur
prior to the completion of L1 speech perception development ~see, e+g+, Eisen-
berg, Shannon, Martinez, Wygonski, & Boothroyd, 2000; Johnson, 2000; Walley
& Flege, 2000!+
An explanation for the results obtained for early learners in Barcelona might
be drawn from the native language magnet model, or NLM ~e+g+, Kuhl, 2000!+
The primary aim of the NLM is to account for the transition from auditory to
language-specific perceptual processing+ The NLM proposes that perception
of the acoustic properties of speech sounds is defined by early experience+
Infants perceptually sort segment-sized units into categories based on the
recurrence of features they have detected in speech input+ This results in a
language-specific mapping between the categories developed for L1 speech
sounds and phonetic input+ In support of this, Kuhl, Williams, Lacerda,
Stevens, and Lindblom ~1992! observed differences in the perception of vow-
els by 6-month-old infants in the United States and Sweden+
Kuhl ~2000, p+ 11854! proposed that infants’ perceptual mapping of ambi-
ent language speech sounds creates a “complex network, or filter, through
which language is perceived+” Perceptual attunement to L1 categories may later
shape the perception of L2 speech sounds+ Interference effects might arise
because of the difficulty inherent in functionally separating L1 and L2 map-
pings ~i+e+, categories! or because a neural commitment to L1 category map-
pings will later influence the processing of L2 speech sounds+
Support for this was provided by Iverson et al+ ~2003!, who examined the
perception of English 0ò0 and 0l0 by NE adults and native Japanese adults in
Tokyo+ Participants rated the acoustic similarity of a grid of 0òa0 and 0la0 stimuli
differing in the frequency of F2 and F3 transitions into the vowel+ Multi-
dimensional scaling analyses suggested that the perception of acoustic-
phonetic dimensions was shaped by attunement to the L1 phonetic system in
a way that might be conceptualized as a “warping” of the phonetic space+
L2 Vowel Perception 5

Unlike NE participants, the native Japanese participants did not show a height-
ened discrimination of stimuli straddling the English 0ò0-0l0 boundary, nor did
they show evidence of a stretching or shrinking of the F3 dimension+ The
authors suggested that native speakers of Japanese develop perceptual maps
that, although well suited for Japanese, may impede acquisition of the English
0ò0-0l0 contrast+ They also suggested that Japanese adults who do manage to
establish new categories for English liquids might develop erroneous long-
term memory representations in which variation in F3 frequency is given too
little prominence+
Importantly, the NLM proposes that constraints on the perception of L2
speech sounds arise from prior experience, not a loss of neural plasticity+
Iverson et al+ ~2003! suggested that L1 interference effects might be “self-
reinforcing” for Japanese adults if, as the result of a warping of the phonetic
space, they fail to experience the same auditory distribution of F3 differences
in English 0ò0 and 0l0 tokens as do children who are learning English as an L1+
However, perceptual learning by adults remains possible, according to the NLM+
Kuhl ~2000, p+ 11855! suggested that the influence of prior experience might
be minimal for children who learn two languages simultaneously in early child-
hood if “two different mappings” are acquired for L1 and L2 speech sounds+
Adult L2 learners might circumvent L1 interference effects if they can recapit-
ulate infants’ experience of L1 speech—that is, if they manage to receive
“exaggerated acoustic cues, multiple instances by many talkers, and massed
listening experience” ~see also McCandliss, Fiez, Protopapas, Conway, &
McClelland, 2002; McClelland, Thomas, McCandliss, & Fiez, 1999!+
Although the findings for early learners in Barcelona are straightforward,
there is reason for caution in accepting the conclusion that an accurate per-
ception of L2 vowels is impossible following establishment of the L1 sound
system+ First, it is widely believed that children learn an L2 rapidly and well
~see Snow, 1987, for review!+ Second, it has been established that early bilin-
guals generally succeed better in producing and perceiving an L2 than late
bilinguals do ~see Flege, 1999, for review!+ If early bilinguals’ capacity for per-
ceptual learning were severely limited, one would expect to observe little if
any perceptual learning by late learners and, by extension, little improvement
in production+ However, the research previously reviewed indicated that adult
L2 learners do make progress in learning to produce L2 vowels+ Finally, con-
clusions drawn from the Barcelona research run counter to models of speech
acquisition such as the NLM and the speech learning model, or SLM+
The SLM ~Flege, 1988, 1992a, 1995, 1999, 2002, 2003a! proposes that even
adults retain the capacities used by infants and children to acquire their L1,
including the ability, in time, to perceive the properties of L2 speech sounds
accurately and to establish new phonetic categories+ However, the SLM
hypothesizes that the likelihood of category formation for L2 speech sounds
depends on perceived cross-language phonetic distance and the state of devel-
opment of L1 phonetic categories+ More specifically, it predicts that the like-
lihood of category formation for L2 speech sounds increases as a function of
6 James Emil Flege and Ian R. A. MacKay

their perceived distance from the closest L1 speech sound+ The SLM also pre-
dicts that, as L1 phonetic categories develop through childhood and into ado-
lescence, they will become more powerful attractors of L2 speech sounds and
thus become more likely to block the formation of new categories for L2 speech
sounds+ In support of this, Baker et al+ ~2002! obtained evidence that the per-
ceptual assimilation of English vowels by Korean vowels was stronger for
Korean adults than children+
One possibility evaluated in this study is that the observed difference
between early learners and native speakers in Barcelona may not be gen-
eralizable to all vowels encountered in an L2+ It is generally agreed that the
perception of L2 vowels will depend, at least initially, on their perceived rela-
tionship to vowels in the L1 inventory ~Best, 1995; Kuhl, 2000!+ For example,
research has shown that L2 vowels tend to be discriminated well if they map
onto ~i+e+, are perceptually assimilated by! two different L1 vowels+ A pair of
L2 vowels will be discriminated less accurately, however, if they are judged to
be instances of a single L1 vowel ~Best, Faber, & Levitt, 1996; Flege, Guion,
Akahane-Yamada, & Downs-Pruitt, 1998!+
Catalan 0e0 and 0E0 may pose an especially difficult perceptual learning task
for native speakers of Spanish+ These vowels occur in a portion of vowel space
that is occupied by a single Spanish vowel, 0e0+ Bosch et al+ ~2000! described
Spanish 0e0 as having @e# and @E# allophones and as occurring near the percep-
tual boundary between Catalan 0e0 and 0E0+ The perceived relationship between
Catalan 0e0 and 0E0 and Spanish 0e0 was not assessed+ However, if Spanish
speakers judge Catalan 0e0 and 0E0 tokens to be equally good instances of Span-
ish 0e0, then the perceptual assimilation model, or PAM ~e+g+, Best, 1995; Best,
McRoberts, & Goodell, 2001! would predict poor discrimination of Catalan 0e0
and 0E0 by Spanish learners of Catalan, regardless of their age of first expo-
sure to Catalan+
Another possibility is that the results obtained for early learners in Barce-
lona will not generalize to all early learners of an L2+ Language-use patterns
are known to influence performance in an L2 ~e+g+, Bahrick, Hall, Goggin,
Bahrick, & Berger, 1994!+ Recent studies have shown that, compared to NI learn-
ers of English who continue to use their L1 often, those who seldom use it
have a better overall pronunciation of English ~Flege, Frieda, & Nozawa, 1997;
Piske, MacKay, & Flege, 2001!, identify English consonants better ~MacKay, Mea-
dor, & Flege, 2001!, and recognize more English words in noise ~Meador, Flege,
& MacKay, 2000!+ The early bilinguals in Barcelona were said to use their L1
frequently ~Pallier et al+, 1997, p+ B11!+ It is therefore possible that early learn-
ers who used Spanish infrequently might not have differed from native speak-
ers of Catalan+

THE PRESENT STUDY

This study examined the perception of English vowels by native speakers of

Italian+ Standard Italian has fewer contrastive vowels ~0i, e, E, a, O, o, u0! than
L2 Vowel Perception 7

English ~Agard & DiPietro, 1964!+ If Italian children who learn English cannot
establish new categories for English vowels, one would expect them ~and a
fortiori Italian adults! to have difficulty discriminating certain pairs of English
vowels+ For example, if NI speakers identify English 0I0 and 0i0 tokens as
instances of Italian 0i0, they should discriminate these English vowels less accu-
rately than NE speakers ~Best, 1995; Best et al+, 1996; Polka, 1995!+
No previous study has examined the perceived relation between English
and Italian vowels+ The aim of the first two experiments, therefore, was to
assess the perceptual assimilation of English vowels by Italian vowels and to
determine which of nine English vowel contrasts would prove difficult for NI
speakers to discriminate+ The participants in experiments 1 and 2 were Italian
university students who had resided in Canada for just 3 months+ These exper-
iments revealed that both members of the 0i0-0I0, 0Á0-0ö0, and 0E0-0æ0 con-
trasts tended to be identified as instances of a single Italian vowel+ These
contrasts may, therefore, have posed the same kind of learning problem for
NI learners of English that Catalan 0e0 and 0E0 pose for native Spanish learn-
ers of Catalan+
Experiments 3 and 4 examined native speakers of Italian who were long-
time residents of Canada+ Half were early learners with an AOA ranging from 2
to 13 years, and half were late learners with an AOA ranging from 15 to 26
years+ Experiment 3 focused on the categorial discrimination of 0i0-0I0, 0Á0-0ö0,
and 0E0-0æ0, and experiment 4 examined the perception of 0i0 and 0I0 using an
error detection task+ As expected ~Flege, 1992a; Flege et al+, 1999; Yamada, 1995!,
the late learners discriminated English vowels less accurately than the early
learners+ The primary question, however, was whether the early learners would
differ from NE speakers+ The early and late learners were subdivided accord-
ing to percentage Italian use ~low L1 use, 1–15%; high L1 use, 25–100%!+ Flege
et al+ did not observe a difference in English vowel discrimination for early
learners differing in percentage Italian use+ However, the difference between
the early-low and early-high groups approached significance ~ p 5 +08!+ Obtain-
ing a significant L1 use effect was considered more likely in this study because
the L1 use difference between the early-low and early-high groups was larger
than in the previous study+ If the early-high but not the early-low group were
found to discriminate English vowels less accurately than the NE group,
it would challenge the view that an accurate perception of L2 vowels is impos-
sible following establishment of the L1 sound system+ Another question
addressed by experiment 3 was whether, as predicted by the SLM, some late
learners would establish new categories for English vowels and discriminate
English vowels as accurately as NE speakers+

EXPERIMENT 1

The purpose of this experiment was to examine the perception of English vow-
els by NI university students who had recently arrived in Canada+ Vowel per-
ception was evaluated using an oddity discrimination test that has been used
8 James Emil Flege and Ian R. A. MacKay

in recent L2 research ~Flege, 2003b; Flege et al+, 1998, 1999; Guion, Flege,
Akahane-Yamada, & Pruitt, 2000!+ The test was categorial in that each vowel
category was represented by multiple natural tokens+

Method

Participants. Two groups of university students participated in Ottawa,

Ontario+ One group ~3 males, 9 females! consisted of native speakers of Cana-
dian English enrolled at the University of Ottawa+ The other group ~3 males, 9
females! consisted of native speakers of Italian+ The NI students, who had the
same age ~M 5 22 years! and years of formal education ~M 5 15 years! as the
NE students, had all been living in Canada for 3 months at the time of testing+
They were enrolled in a special one-semester program at Carleton University
as part of their training in translation at an Italian university+ The Italian stu-
dents reported having studied English in Italy for an average of 9 years ~range 5
3–15 years! beginning at an average age of 12 years ~range 5 7–18 years!+ They
came from a variety of regions in Italy ~3 from Puglia, 3 Molise, 2 Sicilia, 2
Abruzzo, 1 Umbria, 1 Piemonte, 1 Lombardia! and so were likely to have learned
somewhat different L1 vowels as children ~e+g+, Canepari, 1986!+

Stimuli. The perceptual stimuli consisted of consonant-vowel-consonant

~CVC! English words produced by adult native speakers of Canadian English
~4 male, 1 female!+ The words were formed by inserting the vowels 0i0, 0I0,
0e I0, 0E0, 0æ0, 0ö0, and 020 into a 0b_d0 context and the vowels 0Á0 and 0ö0 into
a 0k_d0 context+ Vowels in the 0b_d0 context ~e+g+, bead, bid ! were used to test
the 0i0-0I0, 0I0-0E0, 0e I0-0E0, 0e I0-0i0, 0E0-0æ0, 0e I0-0I0, 0æ0-0ö0, and 020-0ö0 con-
trasts, and vowels in the 0k_d0 context ~e+g+, cod, cud ! were used to test the
0Á0-0ö0 contrast+
The words were digitized ~22+05 kHz! and then normalized for peak inten-
sity+ The design required that there be within-category variation in the tokens
representing each vowel category of interest+ As expected, acoustic analyses
revealed higher formant frequency values in vowels spoken by the female talker
than by the four male talkers and also differences in the duration, midpoint
formant frequency values, and amount of formant movement among the five
tokens of each vowel+ A preliminary auditory evaluation revealed that despite
the existence of considerable within-category variation, NE-speaking listeners
judged the vowels in each of the CVC stimuli to be good instances of their
intended categories+

Procedure. All participants were tested individually in a quiet room using

a notebook computer+ The Italian students were tested on the Carleton Uni-
versity campus, whereas the NE students were tested at the University of
Ottawa+ Instructions were administered in English to all participants in this
and subsequent experiments+
L2 Vowel Perception 9

The three CVC stimuli presented on each trial were always produced by
three different talkers+ A total of 20 trials tested each of the nine contrasts+
Half the trials, called change trials ~e+g+, 0bit0 0bIt0 0bit0!, contained an odd
item out that occurred with near-equal frequency in all three possible serial
positions+ The remaining trials, called no-change trials ~e+g+, 0be It0 0be It0 0be It0!,
contained three physically different instances of a single vowel category+ The
interstimulus interval between the three stimuli in all trials was 1+2 s+
The decision to include both change and no-change trials was motivated
by the widely held view ~e+g+, Francis & Nusbaum, 2002; Guenther, Husain,
Cohen, & Shinn-Cunningham, 1999; Kuhl, 1980! that the formation of a pho-
netic category will increase sensitivity to differences between members of the
new category and other categories but lead to a decrease in sensitivity to
differences among members of the new category+ The change trials tested the
participants’ ability to distinguish vowels drawn from two different catego-
ries+ The vowels in no-change trials differed audibly but not in a phonetically
relevant manner+ The no-change trials therefore tested the participants’ abil-
ity to ignore audible but phonetically irrelevant within-category variation+
The stimuli were presented via headphones at a self-selected comfortable
volume level+2 Feedback was provided during a 20-item practice session using
nontest stimuli ~0bUt0 and 0bot0 tokens! before the experiment began+ Feed-
back was not provided during the experiment+ However, five extra trials were
presented for practice at the beginning of the experiment+ The participants
were told to focus their attention on the vowels in the three CVC words pre-
sented on each trial+ They were instructed to click a button marked “1,” “2,”
or “3” to indicate the serial position of the odd item out, if they heard one+
They were told to click a fourth button marked “same” if they heard three
different instances of one vowel+ A trial could be replayed, but responses could
not be changed once given+
An A' score was calculated for each contrast to reduce the possible effect
of response bias+ The A' scores were based on the proportion of hits and false
alarms+ Hits were defined as the correct selection of the odd item out in change
trials ~maximum 5 10 per contrast!+ False alarms were defined as the incor-
rect selection of an odd item out in no-change trials ~maximum 5 10 per con-
trast!+3 An A' score of 1+000 indicated perfect sensitivity to a vowel contrast
~i+e+, correct responses to all 10 change and all 10 no-change trials!+ A score
of +500 represented a theoretically defined chance level of response ~see
Snodgrass, Levy-Berger, & Haydon, 1985!, that is, a lack of sensitivity+

Results and Discussion

The NE students’ scores were higher ~M 5 +996, SD 5 +006! than the NI stu-
dents’ scores ~M 5 +780, SD 5 +061!+ However, as shown in Figure 1, the size of
differences between the two groups varied as a function of vowel contrast+
The NE students obtained perfect scores for 020-0ö0 and near-perfect scores
10 James Emil Flege and Ian R. A. MacKay

Figure 1. Mean discrimination ~A' ! of nine English vowel contrasts by the

native English ~NE! and native Italian ~NI! students in experiment 1+ The error
bars bracket 61+0 SE+

for the remaining eight English vowel contrasts+ Accordingly, the 020-0ö0 scores
were excluded from the group ~NI vs+ NE! by contrast ~eight levels! ANOVA
examining the discrimination scores+ This analysis yielded significant main
effects of group, F~1, 22! 5 151+0, p , +01, and contrast, F~7, 154! 5 10+3, p ,
+01, and a significant two-way interaction, F~7, 154! 5 10+2, p , +01+
The two-way interaction was explored by a series of independent t-tests
~each with df 5 22! testing the simple effect of group for each contrast+ These
tests revealed that the Italian students obtained significantly lower scores than
the NE students for each of the eight contrasts examined in the ANOVA ~Bon-
ferroni adjusted p , +01!+ A one-sample t-test was conducted to evaluate the
NI students’ discrimination of the ninth contrast examined, 020-0ö0+ Their scores
for 020-0ö0 were significantly lower than the mean score of 1+000 obtained for
the NE students, t 5 2+54, p 5 +019+
The Italian students discriminated all nine English contrasts more poorly
than the NE students+ A series of one-sample t-tests was carried out to deter-
mine how many contrasts were discriminated at a significantly above-chance
rate+ The Italian students’ scores were compared to +500, the value indicating
a theoretical lack of sensitivity ~Snodgrass et al+, 1985!+ The students’ scores
significantly exceeded +500 ~Bonferroni adjusted p , +05! for all contrasts except
the two receiving the lowest discrimination scores ~0E0-0æ0, t 5 1+84;
0Á0-0ö0, t 5 1+88!+ This suggested that the Italian students were at least par-
tially aware of differences between certain pairs of English vowels+ The rela-
L2 Vowel Perception 11

tive difficulty of the nine English contrasts was explored further in a one-way
ANOVA, which yielded a significant effect of contrast, F~8, 88! 5 13+7, p , +01+
Tukey’s HSD procedure indicated that the Italian students obtained signifi-
cantly lower scores for both 0E0-0æ0 and 0Á0-0ö0 than for six other contrasts
~0i0-0I0, 0e I0-0i0, 0e I0-0I0, 0æ0-0ö0, 0e I0-0E0, 020-0ö0!, for 0I0-0E0 than for three other
contrasts ~0æ0-0ö0, 0e I0-0E0, 020-0ö0!, and for 0i0-0I0 than 020-0ö0 ~ p , +05!+
In summary, Italian students who lived in Canada for 3 months discrimi-
nated nine pairs of English vowels less accurately than age-matched NE stu-
dents+ However, the English vowel contrasts varied considerably in difficulty+
The Italian students discriminated seven of the nine contrasts that were exam-
ined at significantly above-chance rates+ They obtained significantly lower
scores for 0E0-0æ0, 0Á0-0ö0, 0I0-0E0, and 0i0-0I0 than for one or more of the other
contrasts examined+ The aim of the next experiment was to help account for
differences between the nine contrasts+

EXPERIMENT 2

The aim of this experiment was to assess the perceived relation between the
English vowel stimuli used in experiment 1 and Italian vowels+ Research within
the framework of the PAM ~Best, 1995! suggests that contrastive L2 vowels
that are identified as instances of two different L1 vowel categories will be
relatively easy for L2 learners to discriminate+ Conversely, the PAM predicts
less accurate discrimination of contrastive L2 vowels that are identified as
instances of a single L1 vowel category+

Procedure

The Italian students ~described previously! participated immediately after com-

pleting experiment 1+ The CVC stimuli from experiment 1, along with booed
~0u0! and bode ~0o0! tokens spoken by the same five NE speakers, were pre-
sented randomly via headphones+ Responses were written on a specially pre-
pared answer sheet rather than recorded by the notebook computer used for
testing+ This is because two different types of judgments were needed for each
vowel stimulus+ Each stimulus was aurally presented twice in a row+ When
hearing a stimulus for the first time, the participants classified its vowel as
Italian 0i0, 0e0, 0E0, 0a0, 0o0, 0O0, or 0u0+4 Following the second presentation, the
participants rated the stimulus vowel for degree of similarity to the Italian
vowel just selected using a scale that ranged from 1 ~very different! to 5 ~very
similar!+ The participants were required to give both a classification response
and a goodness-of-fit rating before proceeding to the next trial+
No training was provided for either the classification or rating task+ How-
ever, we were concerned that differences in the participants’ L1 vowel sys-
tems might influence the results+ For example, distinctions between 0e0-0E0
and 0o0-0O0 are taught in Italian elementary schools because they do not exist
12 James Emil Flege and Ian R. A. MacKay

in certain varieties or dialects of Italian+ As a precaution, the participants were

given a written list of Italian keywords containing the seven vowels of stan-
dard Italian before the experiment began+ They were asked to repeat the key-
words aloud and pay special attention to the distinction between 0e0 and 0E0
and between 0o0 and 0O0+ One of the 12 Italian students reported that these
distinctions do not exist in her native dialect of Italian+

Results and Discussion

Table 1 shows the percentage of times that the English vowel stimuli were
identified as instances of each Italian vowel category+ The percentages in ital-
ics indicate the modal classification of each English vowel+ Both vowels in
three contrasts received the same modal classification: English 0E0 and 0æ0 as
Italian 0E0; 0Á0 and 0ö0 as Italian 0a0; and 0i0 and 0I0 as Italian 0i0+ However,
different modal classifications were obtained for the English vowels compris-
ing the remaining six English vowel contrasts+ Table 1 also shows, in paren-
theses, the average ratings assigned to the stimuli that were classified in terms
of each Italian vowel category+ The most notable aspect of these data is that
the English 020 stimuli received much lower goodness-of-fit ratings than the
other English vowel stimuli, especially 0i0 and 0u0+
A question of interest was whether the perceptual assimilation data could
provide an explanation as to why certain English vowels were more difficult
than others for the Italian students to discriminate in experiment 1+ To address

Table 1. Classification of the English vowel stimuli as one of seven Italian

vowels in experiment 1

Mean percentage of classification ~goodness-of-fit rating!

Stimulus 0i0 0e0 0E0 0a0 0o0 0O0 0u0

0bit0 87~4+2! 8~3+2! 5~4+3! — — — —

0bIt0 65~2+9! 35~4+0! — — — — —
0be I t0 8~2+8! 62~3+3! 30~3+5! — — — —
0bEt0 — 47~3+6! 53~3+8! — — — —
0bæt0 — 10~3+2! 75~3+8! 15~2+6! — — —
0böt0 — — — 93~3+7! — — 3~2+0!
0b2t0 18~1+8! 63~1+6! 15~1+6! — — — —
0kÁd0 — — — 47~3+4! 20~3+7! 33~4+1! —
0köd0 — — — 68~3+4! 25~3+3! 7~4+0! —
0bot0 — — — 3~4+5! 75~3+6! 22~3+5! —
0but0 — — — — — 3~4+0! 95~4+2!
Note+ Percentages less than 2% are not shown+ The goodness-of-fit ratings ranged from 1 ~very different! to 5 ~very
similar!+ The values in parentheses are mean goodness-of-fit ratings+
L2 Vowel Perception 13

this question, classification overlap scores were computed for each contrast+
The computation can be illustrated as follows+ The Italian students classified
the English 0E0 and 0æ0 tokens as Italian 0e0 in 47% and 10% of instances,
respectively+ This gave a 10% overlap in use of the Italian 0e0 category+ The
0E0 and 0æ0 tokens were classified as Italian 0E0 in 53% and 75% of instances,
giving a 53% overlap in use of the 0E0 category+ The two partial overlap scores
yielded a score of 63% for the 0E0-0æ0 contrast+
There was a high degree of overlap for three of the four English vowel
contrasts that were most difficult for the Italian students to discriminate in
experiment 1 ~viz+, 0E0-0æ0, 0Á0-0ö0, 0i0-0I0!+ A single Italian vowel was used in
63% of instances to classify both the English 0E0 and 0æ0 tokens, in 74% of
instances to classify both the English 0Á0 and 0ö0 tokens, and in 72% of
instances to classify both the English 0i0 and 0I0 tokens+ Conversely, there was
little classification overlap for two of the three contrasts that were discrimi-
nated most accurately by the Italian students ~viz+, 0ö0-0æ0 and 020-0ö0!+ Spe-
cifically, a single Italian vowel was used in only 15% of instances to classify
both 0ö0 and 0æ0, and the same Italian vowel was never used to classify both
020 and 0ö0+
These results are consistent with predictions generated by the PAM ~Best,
1995!+ However, the results for two other contrasts diverged from the general
pattern just described+ The high classification overlap score computed for
0e I0-0E0 ~viz+, 87%! led to the expectation of poor discrimination+ However, the
Italian students discriminated 0e I0-0E0 much better than the three other con-
trasts receiving high classification overlap scores ~viz+, 0E0-0æ0, 0Á0-0ö0, and
0i0-0I0!+ An inspection of the classifications given by individual students pro-
vided some insight into this anomaly+ When considered on an individual basis,
the overlap of Italian vowel categories used to classify 0e I0-0E0 averaged only
40%+
The results for 0I0-0E0 also diverged from the general pattern+ The rela-
tively low classification overlap score computed for 0I0-0E0 ~viz+, 35%! led to
the expectation of relatively good discrimination+ However, 0I0-0E0 received
lower discrimination scores than all but two other contrasts ~viz+, 0E0-0æ0 and
0Á0-0ö0!+ The difficulty of 0I0-0E0 might be explained in part by considering the
acoustic specification of these vowels+ Most vowels that are adjacent to one
another in the English vowel space differ in terms of midpoint formant fre-
quency values, duration, and formant movement patterns+ However, English
0I0 and 0E0 differ relatively little in terms of their midpoint formant frequen-
cies and duration and do not show a differing pattern of formant movement
~Hillenbrand, Clark, & Nearey, 2001!+ This might explain why NE-speaking lis-
teners sometimes misidentify English 0I0 and 0E0 tokens that have been pro-
duced by other NE speakers ~see Flege, 1988, for review!+ The results obtained
here for 0I0-0E0 suggest indirectly, therefore, that nonnative discrimination of
L2 vowels may depend on more than just cross-language patterns of percep-
tual assimilation+
14 James Emil Flege and Ian R. A. MacKay

EXPERIMENT 3

This experiment examined discrimination of English vowels by long-time NI

residents of Canada using the stimuli and procedures from experiment 1+ Analy-
ses focused on the 0E0-0æ0, 0Á0-0ö0, and 0i0-0I0 contrasts, which showed a
single-category perceptual assimilation pattern in experiment 2+ The PAM ~Best,
1995! predicts that contrasts of this type will be difficult for L2 learners to
discriminate+

Method

Participants. Eighteen NE and 72 NI speakers participated+ The NI partici-

pants were required to have been born in Italy and have immigrated to Can-
ada between the ages of 2 and 13 years ~early L2 learners! or 15 and 26 years
~late L2 learners!+ They also had to report using Italian between 1% and 15%
~low L1 use! or between 25% and 100% ~high L1 use! of the time+ Length of
residence ~LOR! in Canada was not used as a selection criterion+ However, all
but two of the 72 NI participants had lived in Canada for more than 10 years,
and all but three had lived there for more than 20 years+
The NI participants were assigned to one of four groups of 18 each based
on their AOA in Canada and self-reported percentage use of Italian+ The early
learners who reported using Italian relatively seldom and often were desig-
nated the early-low and early-high groups, respectively+ The late learners who
reported using Italian seldom and often were designated the late-low and late-
high groups, respectively+ Characteristics of the four groups are summarized
in Table 2+ The NI participants were born in one of 13 Italian regions ~24 in
Abruzzo, 12 Calabria, 8 Sicilia, 7 Veneto, 6 Campania, 4 Basilicata, 3 Lazio, 2
Friuli, 2 Puglia, 1 Lombardia, 1 Marche, 1 Piemonte, 1 Toscana!+ Place of birth
did not vary systematically across the four groups+ The age of the NE speak-
ers was comparable ~M 5 50, SD 5 5! to that of the four NI groups+ None of
the 90 participants reported a history of auditory disorder, and all passed a
pure-tone hearing screening at octave frequencies between 500 and 4,000 Hz
~re: 35 dB HL!+
The Language Background Questionnaire ~LBQ! shown in Appendix A was
administered to the NI participants before testing began+ The experimenter
read each question and recorded all answers to prevent variation in reading
ability from influencing the results obtained+ Analysis of the LBQ revealed that
the early learners had received substantially more education in Canada than
in Italy ~M 5 12+6 vs+ 2+2 years!, whereas the late learners had received sub-
stantially less education in Canada than in Italy ~M 5 1+7 vs+ 9+0 years!+ Infor-
mal interactions with the participants revealed that they had received little, if
any, exposure to English in Italy before arriving in Canada+
The NI participants were asked to estimate their percentage use of Italian
in the 5 years, 5 months, and 5 weeks prior to testing+ The three estimates
L2 Vowel Perception 15

Table 2. Characteristics ~means, standard deviations, ranges! of the five

groups of participants in experiment 3

Learner groups Gender CA AOA % use LOR NII Educ

NE 9m, 9f 50~4! — — — — —
39–57
Early low 8m, 10f 50~4! 7~3! 7%~4! 42~4! 2+8~1+4! 14~3!
42–58 2–13 1–13 36–50 1–7 10–18
Early high 8m, 10f 49~6! 8~4! 43%~15! 40~4! 5+0~1+7! 11~6!
35–61 2–13 25–80 33–49 2–10 2–24
Late low 10m, 8f 51~7! 20~3! 10%~5! 31~8! 2+6~1+0! 2~2!
29–62 15–25 2–15 4–42 0–5 0–6
Late high 8m, 10f 49~8! 20~3! 53%~13! 29~9! 4+4~1+6! 2~2!
29–57 15–26 30–75 8–39 2–7 0–8
M 49~6! 14~7! 28%~23! 36~9! 3+7~1+8! 7~6!
Note+ CA 5 chronological age in years; AOA 5 age of arrival in Canada in years; % use 5 self-reported percentage use
of Italian; LOR 5 length of residence in Canada in years; NII 5 number of interlocutors with whom Italian was used;
Educ 5 years of education in Canada in years+ The values in parentheses are standard deviations+

were averaged in Table 2 because they were highly correlated ~ p , +001!+ Par-
ticipants in the early-low and late-low groups reported using Italian 8% of the
time on the average, whereas those in the early-high and late-high groups
reported using Italian 48% of the time+ The AOA of the early and late learners
averaged 8 and 20 years, respectively+ An ANOVA revealed that the low-L1-use
and high-L1-use participants did not differ significantly according to AOA,
F~1, 68! 5 0+7, p . +10+ Another ANOVA revealed that the late learners used
Italian more than the early learners, F~1, 68! 5 7+3, p , +01+ However, AOA and
L1 use did not interact significantly in an ANOVA examining percentage Italian
use, F~1, 68! 5 2+45, p . +10+
The NI participants’ L1 use estimates appear to have been valid and reli-
able+ They were asked to name the persons with whom they spoke Italian+
The number of named interlocutors was examined in a two-way ANOVA+ Par-
ticipants assigned to the high-L1-use groups named significantly more per-
sons than those assigned to the low-L1-use groups, F~1, 68! 5 34+1, p , +01+
However, the number of persons named by participants in the early and late
groups did not differ significantly, F~1, 68! 5 0+3, p . +10, nor did the AOA 3
L1 Use interaction reach significance, F~1, 68! 5 0+27, p . +10+
In addition to providing global percentage Italian use estimates, the NI par-
ticipants were also asked to indicate their percentage Italian use in a variety
of contexts ~at work, while shopping, on the telephone, at home, in social sit-
uations, with friends, and with family members!+ The average contextualized
estimates given by the four NI groups are shown in Figure 2+ These findings
suggest that participants in the early-low and late-low groups used Italian
almost exclusively with family members+ An average of the contextualized esti-
mates was computed for each NI participant+ These average estimates were
16 James Emil Flege and Ian R. A. MacKay

Figure 2. Mean percentage use of Italian reported by the four groups of par-
ticipants in experiment 3 at work ~WO!, while shopping ~SH!, on the telephone
~TE!, at home ~HO!, at social events ~SO!, with friends ~FR!, and with family
members ~FA!+

correlated with the global Italian use estimates reported in Table 2, r~70! 5
+91, p , +01+

Procedures. All 90 participants were tested individually in a quiet room

located at a predominantly Italian Roman Catholic parish in Ottawa, Ontario+
The stimuli and procedures were the same as those used in experiment 1+

Results and Discussion

The discrimination scores for the five groups are shown in Figure 3+ The NE
and early-low groups obtained similar mean scores for the nine contrasts ~M 5
+988 vs+ +985!, whereas participants in the other three groups obtained lower
average scores ~early high 5 +957, late low 5 +927, and late high 5 +869!+
Figure 4 shows the scores for 0E0-0æ0, 0Á0-0ö0, and 0i0-0I0 in greater detail+ A
series of AOA 3 L1 use ANOVAs revealed that the early learners discrimi-
nated all three of these contrasts significantly better than the late learners:
0E0-0æ0, F~1, 68! 5 19+2, p , +01; 0Á0-0ö0, F~1, 68! 5 29+1, p , +01; 0i0-0I0,
F~1, 68! 5 6+0, p , +05+ Also, the low-L1-use participants discriminated all three
contrasts better than the high-L1-use participants: 0E0-0æ0, F~1, 68! 5 5+8,
L2 Vowel Perception 17

Figure 3. Mean discrimination of nine English vowel contrasts by native

English ~NE! speakers and four native Italian ~NI! groups in experiment 3+ Scores
for the NI students in experiment 1 are included for comparison+

p , +05; 0Á0-0ö0, F~1, 68! 5 13+1, p , +01; 0i0-0I0, F~1, 68! 5 5+1, p , +05+ No
significant AOA 3 L1 Use interactions were obtained: 0E0-0æ0, F~1, 68! 5 1+8,
p . +10; 0Á0-0ö0, F~1, 68! 5 0+1, p . +10; 0i0-0I0, F~1, 68! 5 0+3, p . +10+
Differences between the NE group and the four NI groups were evaluated
in a series of one-way ANOVAs+ The effect of group was significant for all three
contrasts: 0E0-0æ0, F~4, 85! 5 10+2, p , +01; 0Á0-0ö0, F~4, 85! 5 17+5, p , +01;
0i0-0I0, F~4, 85! 5 5+5, p , +01+ The four NI groups were compared to the NE
group in a series of t-tests ~df 5 34! to evaluate native versus nonnative differ-
ences+ Participants in the late-low, late-high, and early-high groups, but not
those in the early-low group, obtained lower scores than the NE group for
0Á0-0ö0 ~Bonferroni adjusted p , +05!+ Participants in the late-low and late-high
groups obtained lower scores than the NE group for 0E0-0æ0 ~ p , +05!+ The
difference between the early-high and NE groups for 0E0-0æ0 was marginally
significant ~ p 5 +06!, but the difference between the early-low and NE groups
was nonsignificant ~ p . +10!+ Only the late-low and late-high groups differed
significantly from the NE group for 0i0-0I0 ~ p , +05!+
The scores obtained for each of the 72 NI participants for 0E0-0æ0, 0Á0-0ö0,
and 0i0-0I0 were evaluated to determine if they fell within 62+0 SDs of the NE
groups’ mean scores+ The late learners met the 2-SD criterion in 32% of 216
~3 contrasts 3 72! possible instances+ The early learners met the 2-SD cri-
terion in 81% of instances+5 Chi-square tests revealed that more early than
late learners met the criterion for each contrast: 0Á0-0ö0, x 2 ~1! 5 10+9, p , +05;
18 James Emil Flege and Ian R. A. MacKay

Figure 4. Mean discrimination of ~a! 0E0-0æ0, ~b! 0Á0-0ö0, and ~c! 0i0-0I0 by four
native Italian ~NI! groups in experiment 3+ The error bars bracket 61+0 SE+
The reference lines show the mean scores obtained by the native English ~NE!
and NI students tested in experiment 1+

0E0-0æ0, x 2 ~1! 5 11+0, p , +05; 0i0-0I0, x 2 ~1! 5 3+8, p , +05+ To obtain a high
discrimination score, participants had to correctly choose the odd item out
in change trials and also ignore phonetically irrelevant but auditorily accessi-
ble within-category differences ~e+g+, the gender of the talker! in no-change
trials+ These findings therefore support the SLM hypothesis that, although indi-
viduals of all ages retain the capacity for category formation, early L2 learn-
ers are more likely than late L2 learners to establish new categories for L2
speech sounds+

Multiple Regression Analyses. Exploratory multiple regression analyses

were run to examine the relation between the six participant variables shown
in Table 2 and vowel discrimination+ The analyses were necessarily explor-
atory because, as expected from previous research ~e+g+, Bahrick et al+, 1994;
L2 Vowel Perception 19

Flege, 1998; Yeni-Komshian, Flege, & Liu, 2000!, the participant variables were
intercorrelated+
As summarized in Table 3, there was a strong correlation between the bilin-
guals’ AOA in Canada and how many years of education they had received in
English-medium schools in Canada+ All participants who arrived in Canada as
children were soon enrolled in school, whereas many later-arriving partici-
pants received no education in Canada+6 The years-of-education variable, in
turn, was correlated significantly with other variables+ A relatively large amount
of education was associated with a relatively long LOR in Canada, a relatively
young chronological age at the time of testing, and a relatively low self-
estimated percentage use of Italian+ Not surprisingly, the higher the self-
estimates of percentage Italian use, the more specific individuals the bilingual
participants tended to name as persons with whom they spoke Italian+ Finally,
a relatively lengthy residence in Canada was associated with a relatively early
arrival in Canada and a relatively old age at the time of testing+
Two forward, step-wise multiple regression analyses examined the relation
between the six participant variables ~in Table 2! and vowel discrimination+
The criterion variables were the average discrimination scores obtained for
all nine English vowels contrasts and the average score for just the three con-
trasts of special interest+ As summarized in Table 4, years of education in Can-
ada accounted for 37% of the variance in the overall discrimination scores at
step 1, and percentage Italian use accounted for an additional 16% of the vari-
ance at step 2+ Years of education accounted for 37% of the variance in the
scores obtained for 0Á0-0ö0, 0E0-0æ0, and 0i0-0I0, and percentage Italian use
accounted for an additional 12% of the variance+
The failure of AOA to emerge as a significant predictor of vowel discrimi-
nation in either analysis might seem surprising, given the focus on the age of
L2 learning in so much second language acquisition research+ The results
obtained by Flege, Yeni-Komshian, and Liu ~1999! suggest the possibility that

Table 3. Simple Pearson correlations between the

participant variables in Table 2

Educ LOR CA % use NII

AOA 2+86** 2+66** +19 +18 2+15

Educ — +49* 2+26* 2+25* +10
LOR — — +61** +12 +01
CA — — — +04 2+15
% use — — — — +42**
NII — — — — —
Note+ AOA 5 age of arrival in Canada in years; Educ 5 years of education in Canada in years;
LOR 5 length of residence in Canada in years; CA 5 chronological age in years; % use 5 self-
reported percentage use of Italian; NII 5 number of interlocutors with whom Italian was used+
For each correlation, df 5 70+
*p , +05+ **p , +01+
20 James Emil Flege and Ian R. A. MacKay

Table 4. Multiple regression analyses examining the relation between

participant variables ~see Table 2! and the vowel discrimination scores
obtained in experiment 3 for 72 Italian-English bilinguals

R-square
Criterion variable Predictor variable Step R-square change F p

Average discrimination Years of education 1 +373 +373 55+1 +0000

of nine contrasts in Canada ~+364! ~+364!
Self-reported 2 +533 +159 23+5 +0000
Italian use ~+512! ~+148!
Average discrimination Years of education 1 +374 +374 51+0 +0000
of 0Á0-0ö0, 0E0-0æ0, 0i0-0I0 in Canada ~+365! ~+365!
Self-reported 2 +493 +119 16+2 +0001
Italian use ~+479! ~+114!
Note+ Adjusted R-square values are in parentheses+

the lack of an AOA effect on L2 perception was due to the multicollinearity

mentioned previously+ These authors used a subgroup matching procedure to
control for the effect of variation in years of education in L2-medium schools+
One analysis compared two subgroups of 20 Korean immigrants each that were
matched for AOA in the United States but differed in years of education in the
United States+ These subgroups were not found to differ significantly in over-
all degree of foreign accent+ However, the subgroup consisting of participants
with many years of education displayed significantly greater knowledge of
grammatically regular aspects of English morphosyntax than the group con-
sisting of participants with fewer years of education+ The opposite pattern
was obtained for subgroups of 20 each that consisted of Korean immigrants
who were matched for years of education in English-medium schools but dif-
fered in AOA in the United States+ That is, early-arriving participants were found
to have a significantly better pronunciation of English than later-arriving par-
ticipants when the years-of-education variable was controlled+ However, the
early-arriving and late-arriving Korean participants were not found to differ in
terms of morphosyntax scores+
In the present study, a strong correlation existed between the NI partici-
pants’ AOA in Canada and how long they had attended L2-medium schools in
Canada ~see Table 3!+ AOA was not identified as a predictor of English vowel
discrimination in the regression analyses presented earlier because a margin-
ally stronger correlation existed between the discrimination scores and years
of education—overall average discrimination, r~70! 5 +611, p , +01; discrimi-
nation of 0Á0-0ö0, 0E0-0æ0, and 0i0-0I0, r~70! 5 +612, p , +01—than between the
discrimination scores and AOA—overall average discrimination, r~70! 5 –+572,
p , +01; discrimination of 0Á0-0ö0, 0E0-0æ0, and 0i0-0I0, r~70! 5 –+572, p , +01+
Two additional regression analyses were undertaken in which the years-of-
education variable was excluded from the set of predictor variables+ AOA
L2 Vowel Perception 21

emerged as the dominant predictor of the Italian-English bilinguals’ discrimi-

nation of English vowels in these analyses+ AOA accounted for 33% of vari-
ance in the average discrimination scores ~ p , +01!, and percentage Italian
use accounted for an additional 19% of the variance ~ p , +01!+ AOA accounted
for 33% of the variance in the analysis of the average scores obtained for
0Á0-0ö0, 0E0-0æ0, and 0i0-0I0 ~ p , +01!, and percentage Italian use accounted for
15% of the variance ~ p , +01!+ These results underscore the need for control-
ling factors that are confounded with AOA in research evaluating the effect of
age on L2 performance+

Comparison to the Experiment 1 Results. Previous research ~Flege, Bohn,

et al+, 1997; Ingram & Park, 1997! has suggested that L2 vowel perception is
likely to improve only modestly as the result of several additional years of
residence in a predominantly L2 speaking environment+ The question addressed
here was whether larger amounts of additional L2 input would yield a more
substantial improvement in L2 vowel perception+
The discrimination scores obtained for the NI students in experiment 1 have
been juxtaposed in Figure 3 to the scores obtained in experiment 3+ The Ital-
ian students might be considered late learners because their first extensive
exposure to native English speakers occurred when they arrived in Canada at
the age of 21 years+ Accordingly, independent t-tests were carried out to deter-
mine if the two groups of late learners from experiment 3 obtained signifi-
cantly higher scores for 0Á0-0ö0, 0E0-0æ0, and 0i0-0I0 than the Italian students+
Participants in the late-low group obtained higher scores ~Bonferroni adjusted
p , +05! than the Italian students for all three contrasts: 0Á0-0ö0, t~28! 5 3+00;
0E0-0æ0, t~28! 5 6+82; 0i0-0I0, t~28! 5 4+93+ Participants in the late-high group
obtained significantly higher scores for two contrasts: 0E0-0æ0, t~28! 5 3+78,
p , +05; 0i0-0I0, t~28! 5 3+65, p , +05; 0Á0-0ö0, t~28! 5 1+46, p . +10+ As previously
mentioned, the experienced late learners in experiment 3 obtained discrimi-
nation scores that fell within 2 SDs of the mean scores obtained for age-
matched NE speakers in 32% of instances+ However, none of the Italian students
in experiment 1 obtained scores for 0E0-0æ0, 0Á0-0ö0, or 0i0-0I0 that fell within
62+0 SDs of the mean scores obtained for age-matched NE students+
Participants in the late-low and late-high groups had lived in Canada lon-
ger ~M 5 30+2 years! than the Italian students ~M 5 0+3 years!+ These results
therefore suggest that late learners’ discrimination of L2 vowels improves as
they receive additional native speaker input+ Of course, LOR in a predomi-
nantly L2-speaking environment may not accurately predict amount of L2 native
speaker input ~see Flege & Liu, 2001!+ Moreover, the experienced late learners
differed from the Italian students in more than just LOR+ For example, the Ital-
ian students were younger than the experienced late learners and may have
had greater aptitude for language learning inasmuch as they were studying to
become professional translators+ Both of these differences would have tended
to favor the Italian students, which suggests that the difference between late
22 James Emil Flege and Ian R. A. MacKay

learners with a short versus long LOR in Canada may have been underesti-
mated+ However, an anonymous reviewer speculated that the Italian students
may have received more Italian-accented English input than the late learners
had because much of their early English input was from NI teachers in Italy+
Additional research will therefore be needed to quantify the effect of differing
amounts of native speaker input on the perception of L2 vowels+

EXPERIMENT 4

In experiment 3, participants in the early-low group obtained lower discrimi-

nation scores than the NE group for 0Á0-0ö0 ~ p , +05! and 0E0-0æ0 ~ p 5 +06!+
Neither group of early learners differed significantly from the NE group for
0i0-0I0, however+ The aim of experiment 4 was therefore to determine if either
or both groups of early bilinguals would differ from the NE group in perceiv-
ing 0i0-0I0 if a more difficult perceptual test were employed+
The test used in this experiment required participants to detect mispro-
nunciations of English 0i0 and 0I0+ Previous research has shown that listeners
readily detect segmental errors in L1 words ~e+g+, Cole, 1981; Flege, 1984; Flege
& Hammond, 1982!+ Other research has shown that some NI late learners pro-
duce English 0I0 as an @i#-quality vowel and English 0i0 as an @I#-quality vowel
~Flege et al+, 1999; Piske et al+, 2002!+ Such individuals may have developed a
compromise L1-L2 vowel category that merged the phonetic properties of Ital-
ian 0i0, English 0i0, and English 0I0 ~see e+g+, Flege, 1999!+ If so, they would prob-
ably not be able to detect @i#-for-0I0 or @I#-for-0i0 substitutions in their own
speech or that of others+
The perceptual stimuli used here were short English phrases containing
the vowel 0i0 ~e+g+, you meet some! or the vowel 0I0 ~e+g+, very difficult!+ The
target vowels in some phrases were produced correctly, whereas the vowels
in other phrases were produced incorrectly ~@i#-for-0I0 or @I#-for-0i0 substitu-
tions!+ The participants’ task was to determine if the target vowel in each
phrase had been produced correctly or incorrectly+ We reasoned that a high
rate of detections of both @i#-for-0I0 and @I#-for-0i0 substitutions would require
distinct representations for 0i0 and 0I0 in long-term memory as well as correct
lexicalization of the words containing the target vowels ~see McAllister, Flege,
& Piske, 2002!+

Method

Participants. Sixty-four participants from experiment 3 ~14 NE, 15 early low,

13 early high, 9 late low, and 13 late high! returned 1 year later for this exper-
iment+ Along with 16 new participants drawn from the Italian-speaking com-
munity of Ottawa, they were assigned to five groups, each with 16 members+7
The Italian use estimates given by the NI participants who took part in this
experiment as well as experiment 3 were correlated, r~48! 5 +85, p , +01+ Not
L2 Vowel Perception 23

surprisingly, the mean characteristics of the five groups were very similar to
those presented in Table 2 for the experiment 3 participants+ The NI partici-
pants had a mean age of 50 years ~range 5 30–63 years! and had lived in Can-
ada for an average of 36 years ~range 5 9–51!+ The early learners arrived in
Canada at an earlier age ~M 5 8 years, range 5 3–13! than the late bilinguals
had ~M 5 19 years, range 5 15–28!+ The low-L1-use participants reported using
Italian less ~M 5 8%, range 5 2–15%! than the high-L1-use bilinguals ~M 5 46%,
range 5 29–75%!+

Stimuli. The perceptual stimuli used here consisted of phrases drawn from
an unpublished study in which NI late learners responded extemporaneously
in English to questions about immigration+ The speech samples were digi-
tized, and phrases containing various target vowels were edited out+ The
phrases were then presented to six NE adults with phonetic training+ The lis-
teners’ classifications of the target vowels were used to select one to three
phrases produced by 13 NE speakers and 24 NI late learners+ The selected
phrases contained the target vowels 0i0, 0I0, and 0æ0+ Some target vowels were
identified as intended by the majority of listeners, whereas others were mis-
identified by most listeners in a particular way+
Three sets of phrases containing the target vowel 0i0 were selected as stim-
uli+ The native English-correct ~NE-correct! set contained 0i0 tokens produced
by NE speakers that were transcribed as @i# by at least four of the six listen-
ers+ The native Italian-correct ~NI-correct! set also contained 0i0 tokens that
were transcribed as @i# by the majority of listeners+ However, the 0i0 tokens in
the native Italian-incorrect ~NI-incorrect! set were transcribed as @I# rather than
@i# by the majority of listeners+ The same procedures were used in selecting
three sets of phrases containing the target vowel 0I0+ ~Productions of 0I0 in
the NI-incorrect set were transcribed as @i# by the majority of listeners+! Also,
three sets of phrases containing the target vowel 0æ0 ~incorrect productions
of 0æ0 transcribed as @a# or @Á#! were selected as filler material+

Procedure. The stimulus sets containing the target 0I0 and 0i0 tokens were
presented in counterbalanced order, with the 0æ0 sets in between+ The phrases
were presented via loudspeakers at a comfortable level+ As the phrases were
presented auditorily, a written version of the phrases ~see Appendix B! was
presented on the screen of the notebook computer used for testing+ The tar-
get vowel in each written phrase was replaced by an asterisk+ This was done
to ensure that the participants knew which vowel in each ~auditory! phrase
was to be judged+ For example, the asterisk in very d*fficult indicated that the
target vowel to be judged was 0I0+ ~This assumes, of course, that participants
knew that the word difficult contains 0I0, not 0i0+! The participants were told
to indicate if the target vowel in each phrase had been produced correctly or
incorrectly+ They did so by clicking one of two buttons shown on the com-
puter screen+ A stimulus phrase could be replayed, but a response could not
24 James Emil Flege and Ian R. A. MacKay

be changed once given+ The interval between each response and the next stim-
ulus was 1 s+

Analysis. Five practice stimuli were presented at the beginning of each

block and were not analyzed+ A' scores were computed for responses to the
0i0 and 0I0 targets in the NI-correct and NI-incorrect sets+ The A' scores were
based on the proportion of hits and false alarms ~Snodgrass et al+, 1985!+ Hits
~maximum 5 16! were defined as judgments of target vowels in the NI-correct
sets as correct; false alarms ~maximum 5 16! were defined as judgments of
target vowels in the NI-incorrect sets as correct+ The rationale for not includ-
ing responses to stimuli in the NE-correct set was that phrases in this set,
unlike phrases in the NI-correct and NI-incorrect sets, were produced without
foreign accent+

Results and Discussion

The mean A' scores obtained for the five groups are shown in Figure 5+ The
scores obtained here were considerably lower than the scores obtained for
0i0-0I0 in experiment 3, probably because the target vowels under examina-
tion were not good instances of the 0i0 and 0I0 categories+ However, the pat-

Figure 5. Mean error detection scores obtained for four native Italian ~NI!
groups in experiment 4+ The reference line shows the mean score obtained
for native English ~NE! speakers+ The error bars bracket 61+0 SE+
L2 Vowel Perception 25

tern of between-group differences obtained here was remarkably similar to

the experiment 3 pattern+ A two-way ANOVA examining the scores obtained
for the NI participants yielded significant main effects of AOA, F~1, 59! 5 9+3,
p , +01, and L1 use, F~1, 59! 5 9+5, p , +01, and a nonsignificant interaction,
F~1, 59! 5 0+4, p . +10+ This replicated the results for 0i0-0I0 in experiment 3+
Native-nonnative differences were evaluated by t-tests comparing the scores
obtained for the NE group to the scores for the four NI groups+ Significantly
lower scores were obtained for the early-high, late-low, and late-high groups
than for the NE group, t~30! 5 2+8–3+9, Bonferroni adjusted, p , +05+ However,
the early-low and NE groups did not differ significantly, t~30! 5 +09, p . +10+
This replicated the results obtained for the discrimination of 0E0-0æ0 and 0Á0-0ö0
in experiment 3+

GENERAL DISCUSSION

This study began with two preliminary experiments ~experiments 1 and 2!

examining the perception of English vowels by Italian university students who
had resided in Canada for just 3 months+ The results of these experiments
suggested that the contrasts between English 0Á0-0ö0, 0E0-0æ0, and 0i0-0I0 are
difficult for Italian speakers to discriminate because both members of each
contrast tend to be identified as instances of a single Italian vowel+ The two
principal experiments of the study then examined the perception of 0Á0-0ö0,
0E0-0æ0, and 0i0-0I0 by NI speakers who had lived in Canada for an average of
36 years+ These participants were assigned to one of four groups based on
their AOA in Canada ~early vs+ late! and percentage Italian use ~high L1 use
vs+ low L1 use!+ Experiment 3 focused on the categorial discrimination of
0Á0-0ö0, 0E0-0æ0, and 0i0-0I0 in CVC words+ Experiment 4 tested participants’
ability to differentiate correct from incorrect productions of 0I0 and 0i0 in short
English phrases+
ANOVAs examining the scores from experiments 3 and 4 yielded significant
main effects of AOA and L1 use and nonsignificant two-way interactions+ Lower
scores were obtained for the late L2 learners than for the early L2 learners+
This result is consistent with previous research examining L2 segmental per-
ception ~e+g+, MacKay et al+, 2001; Yamada, 1995!, including studies that focused
on vowel perception ~Baker et al+, 2002; Flege et al+, 1999!+ The lower scores
obtained for high-L1-use than low-L1-use participants were expected from
research examining overall degree of foreign accent ~Piske et al+, 2002!, the
identification of L2 consonants ~MacKay et al+!, and the recognition of L2 words
in noise ~Meador et al+, 2000!+
The primary purpose of this study, however, was to determine if the early
learners differ from NE speakers in perceiving English vowels+ Some previous
research has revealed no difference between early learners and L2 native speak-
ers ~Baker et al+, 2002; Flege et al+, 1999!+ However, research with native Span-
ish learners of Catalan in Barcelona did reveal such differences ~Bosch et al+,
26 James Emil Flege and Ian R. A. MacKay

2000; Pallier et al+, 1997, 2001; Sebastián-Gallés & Soto-Faraco, 1999!, which
suggests that an accurate perception of L2 vowels might be impossible follow-
ing establishment of the L1 sound system+ The hypothesis tested here—that
high-L1-use but not low-L1-use early learners would differ from NE speakers—
was largely confirmed+ The early-low group did not differ from the NE speak-
ers in discriminating 0Á0-0ö0, 0E0-0æ0, or 0i0-0I0 in experiment 3+ However, the
early-high group obtained scores that were significantly lower than the NE
groups’ scores for 0Á0-0ö0, and their scores for 0E0-0æ0 differed from the NE
speakers’ scores at the +06 level+ In experiment 4, the early-high group but not
the early-low group was found to differ significantly from the NE group in an
error detection task focusing on the English 0i0-0I0 distinction+
Two conclusions can be drawn from the results obtained here for early
learners+ Consistent with the results obtained in Barcelona, beginning to learn
an L2 in childhood does not guarantee a nativelike perception of L2 vowels+
On the other hand, establishment of the L1 phonetic system does not guar-
antee that measurable vowel-perception differences will exist between early
learners and L2 native speakers+ The L1 phonetic systems of the early-
high and early-low groups were probably similar when they began to learn
English, for participants in these groups arrived in Canada at the same age+
Therefore, if early learners are prevented from perceiving L2 vowels accu-
rately as the result of interference from L1 vowels ~e+g+, Kuhl et al+, 1992!,
one would have expected comparable results for the early-high and early-
low groups+
The tests administered in experiments 3 and 4 were sufficiently sensitive
to reveal differences between participants in the NE and early-high groups+
Thus, the results for these experiments suggest that the representations devel-
oped for English vowels by participants in the early-low group were function-
ally equivalent+ However, the lack of significant differences between the NE
and early-low groups does not necessarily indicate that the long-term mem-
ory representations developed for English vowels by participants in these
groups were identical+ It is unlikely that NE and early-low group participants
had received identical English input over the course of their lives+ Moreover,
the SLM predicts that when new phonetic categories are established for L2
vowels that are close in vowel space to preexisting L1 vowels, the L1 and L2
vowels will dissimilate ~see Flege, 2002; Flege, Schirru, & MacKay, 2003!+ This
might also lead to subtle perceptual differences between native speakers and
early learners+ It is also possible that residual differences in feature weighting
might distinguish successful early learners from L2 native speakers ~see, e+g+,
Crowther & Mann, 1994; Iverson et al+, 2003!+
Although the AOA and L1 use effects obtained here were straightforward,
their interpretation is not+ Age effects on L2 speech acquisition have been
attributed, among other things, to age-related differences in neural plasticity
~e+g+, Scovel, 1988, 2000! and differences in the state of development of L1 pho-
netic categories ~e+g+, Flege, 1999!+ Such effects might also be attributed to
L2 Vowel Perception 27

factors that are typically confounded with age ~e+g+, Flege, Yeni-Komshian, et al+,
1999!+ For example, there was a strong correlation between the NI partici-
pants’ AOA and how many years of education they had received in English-
speaking Canadian schools+ Years of education, in turn, showed a slightly
stronger correlation with vowel discrimination scores than AOA+ Perhaps the
early learners discriminated English vowels more accurately than the late learn-
ers because they had received more phonetic input from NE speakers during
early stages of L2 learning ~see Flege & Liu, 2001!+ Still another possibility is
that the early and late learners differed in motivation to learn English because
of perceived differences in the social or economic utility of English, or both
~Grenier, 1984; Stevens, 1999!+
Interpretation of the L1 use effect is also uncertain+ The L1 use effect may
have had a psycholinguistic origin+ For example, the Italian system of the high-
L1-use participants might have been activated more strongly than the low-L1-
use participants’ Italian system+ If so, it might have exerted a comparatively
stronger influence on their representations of English vowels, how they pro-
cessed English vowels, or both+ Alternatively, the L1 use effect may have been
due to differences in phonetic input+ For example, the high-L1-use partici-
pants might have been exposed to Italian-accented English more frequently
than the low-L1-use participants+ Another possible explanation is that more
early-low than early-high participants were dominant in English, and L2 dom-
inance contributes to an accurate perception of L2 vowels ~see Flege, MacKay,
& Piske, 2002!+
Still another possible explanation of the observed difference between the
early-low and early-high groups was offered by an anonymous reviewer: The
L1 use effect was actually an effect of differences in L2 use+ The NI partici-
pants were not asked to estimate their use of English ~see Appendix A! because
other research with participants drawn from the same community has shown
that English and Italian use estimates are inversely correlated+ For example,
196 native speakers of Italian living in the Ottawa region were recently asked
to estimate their percentage use of English, Italian, and French+ The estimates
averaged 51+1% for English, 48+0% for Italian, and 0+9% for French+ The corre-
lation between the English and Italian estimates was r~194! 5 –+995+ It is con-
ceivable, therefore, that the low-L1-use participants in this study perceived
English vowels more accurately than the high-L1-use participants because they
used English more and had thus heard English vowels more frequently than
the high-L1-use participants+
Finally, the results obtained here lend support to the SLM hypothesis ~e+g+,
Flege, 1995! that the capacity to establish new vowel categories remains intact
across the life span+ As previously mentioned, Italian students who had lived
in Canada for 3 months had difficulty discriminating English 0Á0-0ö0, 0E0-0æ0,
and 0i0-0I0+ None of the Italian students obtained discrimination scores that
fell within 2 SDs of the mean discrimination scores obtained for age-matched
NE students+ However, the late learners in experiment 3 obtained discrimina-
28 James Emil Flege and Ian R. A. MacKay

tion scores that fell within 2 SDs of the mean value for age-matched NE speak-
ers in 32% of instances+
In conclusion, early learners who continued to use Italian L1 often, but not
those who seldom used Italian, were found to differ significantly from native
speakers of English in perceiving English vowels+ This suggests that the estab-
lishment of the L1 vowel system does not by itself prevent an accurate per-
ception of L2 vowels+ The late learners who were examined in the present
study generally perceived English vowels less accurately than the early learn-
ers+ However, as predicted by the SLM, some late learners were found to per-
ceive English vowels accurately+

~Received 24 February 2003!

NOTES

1+ Sebastián-Gallés and Soto-Faraco ~1999! also examined Catalan 0o0-0O0, 0s0-0z0, and 0S0-0Z0, and
Pallier et al+ ~2001! also examined 0o0-0O0, 0s0-0z0, and 0m0-0n0+
2+ In some categorial discrimination tests ~e+g+, Best et al+, 2001!, the trials testing each contrast
of interest are presented in separate, counterbalanced blocks+ In this study, the trials testing all
nine contrasts were presented in a single, randomized block to increase task difficulty and thus
maximize the likelihood of observing significant between-group differences+
3+ If the proportion of hits ~H! equaled the proportion of false alarms ~FA!, then A' was set to
+500+ If H exceeded FA, then A' 5 +500 1 ~~H – FA! 3 ~1 1 H – FA!!0~~4 3 H! 3 ~1 – FA!!+ However, if FA
exceeded H, then A' 5 +500 – ~~FA – H! 3 ~1 1 FA – H!!0~~4 3 FA! 3 ~1 – H!!+
4+ To prevent possible confusions arising from a lack of familiarity with phonetic symbols, alter-
nate labels were also provided for the mid vowels ~e chiusa and e aperta for 0e0 and 0E0, o chiusa
and o aperta for 0o0 and 0O0!+ These terms are taught in Italian elementary schools+
5+ The NE group’s scores for 0Á0-0ö0 averaged +988 ~SD 5 +032!+ A total of 33 participants met the
2-SD criterion for 0Á0-0ö0 ~17 early low, 9 early high, 4 late low, and 3 late high!+ The NE speakers’
scores for 0E0-0æ0 averaged +990 ~SD 5 +015!, with 44 NI participants meeting the 2-SD criterion ~18
early low, 15 early high, 8 late low, and 3 late high!+ Finally, the NE speakers’ 0i0-0I0 scores averaged
+990 ~SD 5 +015!, with 45 NI participants meeting the 2-SD criterion ~17 early low, 12 early high, 10
late low, and 6 late high!+
6+ The 20 participants with an AOA less than 9 years attended Canadian schools for 14+4 years
on average, whereas the 27 participants with an AOA greater than 17 years attended school for just
1+3 years on average+
7+ The data for one participant in the late-high group was lost due to a technical error+

REFERENCES

Agard, F+, & DiPietro, R+ ~1964!+ The sounds of English and Italian+ Chicago: University of Chicago
Press+
Bahrick, H+, Hall, L+, Goggin, J+, Bahrick, L+, & Berger, S+ ~1994!+ Fifty years of language maintenance in
bilingual Hispanic immigrants+ Journal of Experimental Psychology: General, 123, 264–283+
Baker, W+, Trofimovich, P+, Mack, M+, & Flege, J+ ~2002!+ The effect of perceived phonetic similarity on
non-native sound learning by children and adults+ In B+ Skarabela, S+ Fish, & A+ Do ~Eds+!, Pro-
ceedings of the 26th annual Boston University Conference on Language Development ~pp+ 36–47!+
Somerville, MA: Cascadilla Press+
Best, C+ ~1995!+ A direct realistic perspective on cross-language speech perception+ In W+ Strange
~Ed+!, Speech perception and linguistic experience: Issues in cross-language research ~pp+ 171–
206!+ Timonium, MD: York Press+
Best, C+, Faber, A+, & Levitt, A+ ~1996!+ Perceptual assimilation of non-native vowel contrasts to the
American English vowel system+ Journal of the Acoustical Society of America, 99, 2602+
L2 Vowel Perception 29

Best, C+, McRoberts, G+, & Goodell, E+ ~2001!+ Discrimination of non-native consonant contrasts vary-
ing in perceptual assimilation to the listener’s native phonological system+ Journal of the Acous-
tical Society of America, 109, 775–794+
Bohn, O+-S+, & Flege, J+ ~1992!+ The production of new and similar vowels by adult German learners
of English+ Studies in Second Language Acquisition, 14, 131–158+
Bosch, L+, Costa, A+, & Sebastián-Gallés, N+ ~2000!+ First and second language vowel perception in
early bilinguals+ European Journal of Cognitive Psychology, 12, 189–221+
Bradlow, A+, & Pisoni, D+ ~1999!+ Recognition of spoken words by native and non-native listeners:
Talker-, listener-, and item-related factors+ Journal of the Acoustical Society of America, 106,
2074–2085+
Canepari, L+ ~1986!+ Italiano standard e pronunce regionali @Standard Italian and regional pronuncia-
tions# ~3rd ed+!+ Padua, Italy: Cooperativa Libraria Editrice Università di Padova+
Cole, R+ ~1981!+ Perception of fluent speech by children and adults+ Annals of the New York Academy
of Sciences, 379, 92–109+
Crowther, C+, & Mann, V+ ~1994!+ Use of vocalic cues to consonant voicing and native language back-
ground: The influence of experimental design+ Perception & Psychophysics, 55, 513–525+
Eisenberg, L, Shannon, R+, Martinez, A+, Wygonski, J+, & Boothroyd, A+ ~2000!+ Journal of the Acousti-
cal Society of America, 107, 2704–2710+
Flege, J+ ~1984!+ The detection of French accent by American listeners+ Journal of the Acoustical Soci-
ety of America, 76, 692–707+
Flege, J+ ~1987!+ The production of “new” and “similar” phones in a foreign language: Evidence for
the effect of equivalence classification+ Journal of Phonetics, 15, 47–65+
Flege, J+ ~1988!+ The production and perception of speech sounds in a foreign languages+ In H+ Winitz
~Ed+!, Human communication and its disorders: A review ~pp+ 224–401!+ Norwood, NJ: Ablex+
Flege, J+ ~1991!+ Orthographic evidence for the perceptual identification of vowels in Spanish and
English+ Quarterly Journal of Experimental Psychology, 43, 701–731+
Flege, J+ ~1992a!+ Speech learning in a second language+ In C+ Ferguson, L+ Menn, & C+ Stoel-Gammon
~Eds+!, Phonological development: Models, research, and application ~pp+ 565–604!+ Timonium,
MD: York Press+
Flege, J+ ~1992b!+ The Intelligibility of English vowels spoken by British and Dutch talkers+ In R+ Kent
~Ed+!, Intelligibility in speech disorders: Theory, measurement, and management ~pp+ 157–232!+
Amsterdam: Benjamins+
Flege, J+ ~1995!+ Second-language speech learning: Theory, findings, and problems+ In W+ Strange ~Ed+!,
Speech perception and linguistic experience: Issues in cross-language research ~pp+ 229–273!+ Timo-
nium, MD: York Press+
Flege, J+ ~1998!+ The role of subject and phonetic variables in L2 speech acquisition+ In M+ Gruber, D+
Higgins, K+ Olsen, & T+ Wysocki ~Eds+!, Papers from the 34th annual meeting of the Chicago Lin-
guistic Society: Vol. 2. The panels ~pp+ 213–232!+ Chicago: Chicago Linguistic Society+
Flege, J+ ~1999!+ Age of learning and second-language speech+ In D+ Birdsong ~Ed+!, New perspectives
on the critical period hypothesis for second language acquisition ~pp+ 101–132!+ Mahwah, NJ:
Erlbaum+
Flege, J+ ~2002!+ Interactions between the native and second-language phonetic systems+ In P+ Bur-
meister, T+ Piske, & A+ Rohde ~Eds+!, An integrated view of language development: Papers in honor
of Henning Wode ~pp+ 217–244!+ Trier, Germany: Wissenschaftlicher Verlag Trier+
Flege, J+ ~2003a!+ Assessing constraints on second-language segmental production and perception+
In A+ Meyer & N+ Schiller ~Eds+!, Phonetics and phonology in language comprehension and pro-
duction: Differences and similarities ~pp+ 319–355!+ Berlin: Mouton de Gruyter+
Flege, J+ ~2003b!+ Methods for assessing the perception of vowels in a second language+ In E+ Fava &
A+ Mioni ~Eds+!, Issues in clinical linguistics ~pp+ 19–44!+ Padua, Italy: UniPress+
Flege, J+, Bohn, O+-S+, & Jang, S+ ~1997!+ The effect of experience on non-native subjects’ production
and perception of English vowels+ Journal of Phonetics, 25, 437–470+
Flege, J+, Frieda, A+, & Nozawa, T+ ~1997!+ Amount of native-language ~L1! use affects the pronuncia-
tion of an L2+ Journal of Phonetics, 25, 169–186+
Flege, J+, Guion, S+, Akahane-Yamada, R+, & Downs-Pruitt, J+ ~1998!+ Categorial discrimination of English
and Japanese vowels and consonants by native Japanese and English subjects+ In P+ Kuhl & L+
Crum ~Eds+!, Proceedings of the 16th International Congress on Acoustics and the 135th meeting of
the Acoustical Society of America: Vol. 4+ ~pp+ 2973–2974!+ Woodbury, NY: Acoustical Society of
America+
30 James Emil Flege and Ian R. A. MacKay

Flege, J+, & Hammond, R+ ~1982!+ Mimicry of non-distinctive phonetic differences between language
varieties+ Studies in Second Language Acquisition, 5, 1–18+
Flege, J+, & Hillenbrand, J+ ~1984!+ Limits on phonetic accuracy in foreign language speech produc-
tion+ Journal of the Acoustical Society of America, 76, 708–721+
Flege, J+, & Liu, S+ ~2001!+ The effect of experience on adults’ acquisition of a second language+ Stud-
ies in Second Language Acquisition, 23, 527–552+
Flege, J+, MacKay, I+, & Meador, D+ ~1999!+ Native Italian speakers’ production and perception of English
vowels+ Journal of the Acoustical Society of America, 106, 2973–2987+
Flege, J+, MacKay, I+, & Piske, T+ ~2002!+ Assessing bilingual dominance+ Journal of Applied Psycholin-
guistic Research, 23, 567–598+
Flege, J+, Munro, M+, & Fox, R+ ~1994!+ Auditory and categorical effects on cross-language vowel per-
ception+ Journal of the Acoustical Society of America, 95, 3623–3641+
Flege, J+, Schirru, C+, & MacKay, I+ ~2003!+ Interaction between the native and second language pho-
netic subsystems+ Speech Communication, 40, 467–491+
Flege, J+, Yeni-Komshian, G+, & Liu, S+ ~1999!+ Age constraints on second language learning+ Journal of
Memory and Language, 41, 78–104+
Francis, A+, & Nusbaum, H+ ~2002!+ Selective attention and the acquisition of new phonetic catego-
ries+ Journal of Experimental Psychology: Human Perception and Performance, 28, 349–366+
Gottfried, T+ ~1984!+ Effects of consonant context on the perception of French vowels+ Journal of Pho-
netics, 12, 91–114+
Grenier, G+ ~1984!+ Shifts to English as usual language by Americans of Spanish mother tongue+ Social
Science Quarterly, 65, 537–550+
Guenther, F+, Husain, F+, Cohen, M+, & Shinn-Cunningham, B+ ~1999!+ Effects of categorization and dis-
crimination training on auditory perceptual space+ Journal of the Acoustical Society of America,
106, 2900–2912+
Guion, S+, Flege, J+, Akahane-Yamada, R+, & Pruitt, J+ ~2000!+ An investigation of current models of
second language speech perception: The case of Japanese adults’ perception of English conso-
nants+ Journal of the Acoustical Society of America, 107, 2711–2725+
Hillenbrand, J+, Clark, M+, & Nearey, T+ ~2001!+ Effects of consonant environment on vowel formant
patterns+ Journal of the Acoustical Society of America, 109, 748–763+
Ingram, J+, & Park, S+-G+ ~1997!+ Cross-language vowel perception and production by Japanese and
Korean learners of English+ Journal of Phonetics, 25, 343–370+
Iverson, P+, Kuhl, P+, Yamada, R+, Diesch, E+, Tohkura, Y+, Ketterman, A+, & Siebert, C+ ~2003!+ A percep-
tual interference account of acquisition difficulties for non-native phonemes+ Cognition, 87,
B47–B57+
Johnson, C+ ~2000!+ Children’s phoneme identification in reverberation and noise+ Journal of Speech,
Language, and Hearing Research, 43, 129–143+
Jun, S+-A+, & Cowie, I+ ~1994! Interference for “new” and “similar” vowels in Korean speakers of English,
Ohio State University Working Papers, 43, 117–130+
Kuhl, P+ ~1980!+ Perceptual constancy for speech sound categories in early infancy+ In G+ Yeni-
Komshian, J+ Kavanagh, & C+ Ferguson ~Eds+!, Child phonology: Vol. 2. Perception ~pp+ 41–66!+
San Diego, CA: Academic Press+
Kuhl, P+ ~2000!+ A new view of language acquisition+ Proceedings of the National Academy of Science,
97, 11850–11857+
Kuhl, P+, Williams, K+, Lacerda, F+, Stevens, K+, & Lindblom, B+ ~1992!+ Linguistic experience alters
phonetic perception in infants six months of age+ Science, 255, 606–608+
Mack, M+ ~1989!+ Consonant and vowel perception and production: Early English-French and French-
English bilinguals+ Perception & Psychophysics, 46, 187–200+
MacKay, I+, Meador, D+, & Flege, J+ ~2001!+ The identification of English consonants by native speak-
ers of Italian+ Phonetica, 58, 103–125+
Major, R+ ~1987!+ Phonological similarity, markedness, and rate of L2 acquisition+ Studies in Second
Language Acquisition, 9, 63–82+
Mayo, L+, Florentine, M+, & Buus, S+ ~1997!+ Age of second-language acquisition and perception of
speech in noise+ Journal of Speech and Hearing Research, 40, 686–693+
McAllister, R+, Flege, J+, & Piske, T+ ~2002!+ The influence of the L1 on the acquisition of Swedish
vowel quantity by native speakers of Spanish, English, and Estonian+ Journal of Phonetics, 30,
229–258+
L2 Vowel Perception 31

McCandliss, B+, Fiez, J+, Protopapas, A+, Conway, M+, & McClelland, J+ ~2002!+ Success and failure in
teaching the @r#-@l# contrast to Japanese adults: Predictions of a Hebbian model of plasticity
and stabilization in spoken language perception+ Cognitive, Affective, and Behavioral Neurosci-
ence, 2, 89–108+
McClelland, J+, Thomas, A+, McCandliss, B+, & Fiez, J+ ~1999!+ Understanding failures of learning: Heb-
bian learning, competition for representational space, and some preliminary experimental data+
In J+ Reggia, E+ Ruppin, & D+ Glanzman ~Eds+!, Progress in brain research: Vol. 121. Disorders of
brain, behavior, and cognition—the neurocomputational perspective ~pp+ 75–80!+ Amsterdam:
Elsevier+
Meador, D+, Flege, J+, & MacKay, I+ ~2000!+ Factors affecting the recognition of words in a second
language+ Bilingualism: Language and Cognition, 3, 55–67+
Morrison, G+ ~2002!+ Effects of L1 duration experience on Japanese and Spanish listeners’ perception of
English high front vowels+ Unpublished Master’s thesis, Simon Fraser University, Vancouver,
Canada+
Munro, M+ ~1993!+ Productions of English vowels by native speakers of Arabic: Acoustic measure-
ments and accentedness ratings+ Language and Speech, 36, 39–66+
Munro, M+, & Derwing, T+ ~1995!+ Processing time, accent, and comprehensibility in the perception of
native and foreign-accented speech+ Language and Speech, 38, 289–306+
Munro, M+, Flege, J+, & MacKay, I+ ~1996!+ The effect of age of second-language learning on the pro-
duction of English vowels+ Applied Psycholinguistics, 17, 313–334+
Pallier, C+, Bosch, L+, & Sebastián-Gallés, N+ ~1997!+ A limit on behavioral plasticity in speech percep-
tion+ Cognition, 64, B9–B17+
Pallier, C+, Colomé, A+, & Sebastián-Gallés, N+ ~2001!+ The influence of native-language phonology on
lexical access: Exemplar-based versus abstract lexical entries+ Psychological Science, 12, 445–449+
Patkowski, M+ ~1989!+ Age and accent in a second language: A reply to James Emil Flege+ Applied
Linguistics, 11, 73–89+
Piske, T+, Flege, J+, MacKay, I+, & Meador, D+ ~2002!+ The production of English vowels by fluent early
and late bilinguals+ Phonetica, 59, 49–71+
Piske, T+, MacKay, I+, & Flege, J+ ~2001!+ Factors affecting degree of foreign accent in an L2: A review+
Journal of Phonetics, 29, 191–215+
Polka, L+ ~1995!+ Linguistic influences in adult perception of non-native vowel contrasts+ Journal of
the Acoustical Society of America, 97, 1286–1296+
Rochet, B+ ~1995!+ Perception and production of second-language speech sounds by adults+ In W+
Strange ~Ed+!, Speech perception and linguistic experience: Issues in cross-language speech research
~pp+ 379–410!+ Timonium, MD: York Press+
Schmid, P+, & Yeni-Komshian, G+ ~1999!+ The effects of speaker accent and target predictability on
perception of mispronunciation+ Journal of Speech, Language, and Hearing Research, 42, 56–64+
Scovel, T+ ~1988!+ A time to speak: A psycholinguistic inquiry into the critical period for human speech+
Rowley, MA: Newbury House+
Scovel, T+ ~2000!+ A critical review of critical period research+ Annual Review of Applied Linguistics,
20, 213–223+
Sebastián-Gallés, N+, & Soto-Faraco, S+ ~1999!+ On-line processing of native and non-native phonemic
contrasts in early bilinguals+ Cognition, 72, 111–123+
Snodgrass, J+, Levy-Berger, G+, & Haydon, M+ ~1985!+ Human experimental psychology+ Oxford: Oxford
University Press+
Snow, C+ ~1987!+ Relevance of the notion of a critical period to language acquisition+ In M+ Bornstein
~Ed+!, Sensitive periods in development: Interdisciplinary perspectives ~pp+ 183–209!+ Mahwah, NJ:
Erlbaum+
Stevens, G+ ~1999!+ Age at immigration and second language proficiency among foreign-born adults+
Language in Society, 28, 555–578+
Walley, A+, & Flege, J+ ~2000!+ Effects of lexical status on children’s and adults’ perception of native
and non-native vowels+ Journal of Phonetics, 27, 307–332+
Yamada, R+ ~1995!+ Age and acquisition of second language speech sounds: Perception of American
English 0ò0 and 0l0 by native speakers of Japanese+ In W+ Strange ~Ed+!, Speech perception and
linguistic experience: Issues in cross-language research ~pp+ 305–320!+ Timonium, MD: York Press+
Yeni-Komshian, G+ H+, Flege, J+, & Liu, S+ ~2000!+ Pronunciation proficiency in the first and second
languages of Korean-English bilinguals+ Bilingualism: Language and Cognition, 3, 131–150+
32 James Emil Flege and Ian R. A. MacKay

APPENDIX A

LANGUAGE BACKGROUND QUESTIONNAIRE

The purpose of this questionnaire is to learn something about your language history+
We would like to find out what languages you know, when you first learned them, and
how much you use them+

1+ Your name: _______________________ 2+ Gender: _____ 3+ Today’s date: ________

4+ City and province of birth: _________________________ 5+ Date of birth: ________
6+ What is your 1st language? _____________ 2nd _____________ 3rd _____________
7+ Your age of arrival in Canada: ______________________________________________
8+ Years you have lived in Ottawa: ____________________________________________
9+ Years and places you have lived elsewhere in Canada: _________________________
10+ Please estimate to the nearest 10% how much you speak any kind of Italian in
these places or situations+ Try to base your estimate on your use of Italian over
the past 5 years+

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
While at home
Visiting family
members
At work ~including
volunteer work!
At church or
church functions
Visiting friends
On the telephone
While on vacation
While shopping
At parties and
social gathering

11+ Please estimate, using a percentage ~%!, how much you have spoken Italian in
the past 5 years _____; in the past 5 months _____; in the past 5 weeks _____+
L2 Vowel Perception 33

12+ Please tell me the people you typically speak Italian with, and their relation to
you+

First name or initials Relation to you

1
2
3
4
5
6
7

13+ Please tell me the people you sometimes speak Italian with, and their relation to
you+

First name or initials Relation to you

1
2
3
4
5
6
7

14+ Number of years of formal education in Italy ____ and in Canada ____
15+ Please estimate your ability to speak, understand, read, and write English and
Italian+ Use the number “1” if your ability is poor, “7” if your ability is good, and
numbers in between for ability levels that are in between+

English Italian

1 2 3 4 5 6 7 1 2 3 4 5 6 7

Speaking

Understanding

Reading

Writing
34 James Emil Flege and Ian R. A. MacKay

APPENDIX B

Table B1. Excerpts of extemporaneous speech by NE speakers and NI late

learners of English

Vowel NE-correct NI-correct NI-incorrect

0I0 very d*fferent to l*ve in very d*fficult a

0I0 to l*ve in all d*fferent to l*ve in a
0I0 of l*ving big d*fference been l*ving a
0I0 another c*ty my k*ds they bigger c*ty a
0I0 a c*ty to l*ve in of d*fferent a
0I0 to l*ve in to *taly nice c*ty a
0I0 the k*ds are and b*ld a the k*ds a
0I0 never v*sited are d*fferent big c*ty a
0i0 don’t f*l very I sp*k English do sp*k b
0i0 to d*l with with p*ple I f*l today b
0i0 to d*l with to sp*k ++uh to d*l with b
0i0 sp*k the you n*d something to sp*k English b
0i0 a w*k lot *sier didn’t f*l comfortable b
0i0 several w*ks at you m*t some and r*ding b
0i0 the m*dia I’m sp*king always sp*k English b
0i0 no s*t on I sp*k + + + uh to sp*k English b
Note+ Correct productions of the target vowels were judged by the majority of NE-speaking listeners to be instances
of their intended category, whereas incorrect productions were usually heard as the vowels indicated+ The asterisks
denote the target vowel, either 0I0 or 0i0+
a
@i#-quality realizations of 0I0+
b
@I#-quality realizations of 0i0+