ATTENTION

Information Processing and Beyond

Attention
■ the means by which we actively process a limited amount of information from the enormous
amount of information
– From senses, our stored memories, and our other cognitive processes

■ Includes both conscious and unconscious processes.

■ Conscious processes are relatively easy to study compared to Unconscious processes
■ allows us to use our limited mental resources judiciously by highlighting the stimuli that
interest us.
■ This heightened focus increases the likelihood that we can respond speedily and accurately to
interesting stimuli
■ We are more likely to remember information to which we paid attention than information we
ignored
Main Functions of Attention
■ Signal detection and vigilance
– We try to detect the appearance of a particular
stimulus
– Ex. Detecting unwelcome sights or sound on a
dark street
■ Search
– engaging in an active search for particular
stimuli
– Ex. If we detect smoke, we may engage in an
active search for the source of the smoke
■ Selective Attention
– Attending to some stimuli and ignore others
– Ex. Reading a textbook or listening
■ Divided Attention
– Engaging in more than one task at a time, and
shifting our attentional resources to allocate
them prudently, as needed
– Ex. Talking while driving
Signal Detection
Theory
■ A framework to explain how people pick out the few
important stimuli when they are embedded in a
wealth of irrelevant, distracting stimuli.
■ Used to measure sensitivity to a target’s presence.
■ The presence of a target is usually difficult to detect.
■ Thus, we make detection judgments based on
inconclusive information with some criteria for target
detections.
■ The number of hits is influenced by where you place
your criteria for considering something a hit.
■ In other words, how willing are you to make false
alarms
Signal Detection Signal Detect a Signal Do Not Detect a
Signal
Theory
Present Hit Miss
The screener The screener fails to
■ Four possible outcomes recognizes a box see the box cutter in
when trying to detect a cutter in the the luggage
stimulus. luggage.

Absent False alarm Correct rejection

The screener The screener
thinks there is a recognizes that there
box cutter in the is no box cutter in
luggage when the luggage, and
there is none. there is indeed none.
 Can be discussed in the context of
attention, perception, or memory:

Attention

• Paying enough attention to perceive objects that are

there
Signal Perception
Detection • Perceiving faint signals that may or may not be beyond
Theory your perceptual range (such as a very high-pitched
tone)

Memory

• Indicating whether you have/have not been exposed to

a stimulus before, such as whether the word
“champagne” appeared on a list that was to be
memorized.
Vigilance

■ Refers to a person’s ability to attend to a field of

stimulation over a prolonged period, during
which the person seeks to detect the
appearance of a particular target stimulus of
interest.
■ When being vigilant, the individual watchfully
waits to detect a signal stimulus that may
appear at an unknown time.
■ Typically, vigilance is needed in settings where a
given stimulus occurs only rarely but requires
immediate attention as soon as it does occur.
Vigilance
■ In vigilance tasks, expectations regarding stimulus
location strongly affect response efficiency.
– Thus, a busy lifeguard may respond quickly to a
signal within a narrow radius of where a signal is
expected to appear.
– But signals appearing outside the concentrated
range of vigilant attention may not be detected as
quickly or as accurately.
■ However, the sudden appearance of a stimulus captures
our attention.
– Thus, we seem to be predisposed to notice the
sudden appearance of stimuli in our visual field.
■ Adaptive advantage of vigilance may have offered to our
ancestral hunter-gatherer forebears.
– They presumably needed to avoid predators and had
to catch prey
Search: Actively Looking

■ Refers to a scan of the environment for

particular features
■ Actively looking for something when you are not
sure where it will appear.
■ As with vigilance, when we are searching for
something, we may respond by making false
alarms.
■ Search is made more difficult by distracters-
nontarget stimuli that divert our attention away
from the target stimulus.
■ False alarms usually arise when we encounter
such distracters while searching for the target
stimulus
Search: Actively Looking

■ The number of targets and distracters affects the

difficulty of the task.
■ Display size is the number of items in each visual
array.
■ Display-size effect
– The degree to which the number of items in a
display hinders (slows down) the search process.
– When studying visual-search phenomena,
investigators often manipulate the display size.
– They then observe how various contributing
factors increase or decrease the display-size
effect.
DISPLAY
SIZE
EFFECT
Distracters
■ cause more trouble under some conditions
than under others
■ Feature search - scan the environment for that
feature. Distracters play little role in slowing
our search in this case.
– Featural singletons - items with
distinctive features, stand out in the
display.
– When featural singletons are targets,
they seem to grab our attention.
– Unfortunately, any featural singletons
grab our attention, including those that
can distract us from finding the target.
■ conjunction search, we look for a particular
combination of features
Search Process Theories
■ Feature-integration theory
– Explains the relative ease of conducting feature searches and the
relative difficulty of conducting conjunction searches
– For each possible feature of a stimulus, each of us has a mental map for
representing the given feature across the visual field.
■ For example, there is a map for every color, size, shape, or
orientation
– (e.g., p, q, b, d) of each stimulus in our visual field.
– during feature searches, we monitor the relevant feature map for the
presence of any activation anywhere in the visual field.
– This monitoring process can be done in parallel (all at once). It therefore
shows no display-size effects.

– However, during conjunction searches, an additional stage of processing

is needed.
– During this stage, we must use our attentional resources as a sort of
mental “glue.”
– This additional stage conjoins two or more features into an object
representation at a particular location.
– In this stage, we can conjoin the features only one object at a time.
– Effects of display size therefore appear.
Search Process
Theories
■ Similarity Theory
– As the similarity between target and distracter
increases, so does the difficulty in detecting the
target stimuli
– Targets that are highly similar to distracters are
relatively hard to detect.
– Targets that are highly disparate from distracters
are relatively easy to detect
– Factors influencing search
■ Similarity between the target and the
distracters
■ Similarity among distracters
Search Process
Theories
■ Guided Search Theory
– Suggests that all searches, whether
feature searches or conjunction
searches, involve two consecutive
stages.
– Parallel stage- simultaneous activation
of a mental representation of all the
potential targets.
– Serial stage- sequential evaluation
each of the activated elements,
according to the degree of activation.
– The person then chooses the true
targets from the activated elements
– the parallel initial stage helps to guide
the evaluation and selection process of
the serial second stage of the search
SELECTIVE AND
DIVIDED ATTENTION
Defining the two processes
Selective Attention

■ The process of focusing on a particular object

in the environment for a certain period of time.
■ Attention is a limited resource
■ selective attention allows us to tune out
unimportant details and focus on what
matters.
Selective Attention
Theories
■ Broadbent’s Model
– We filter information right after it is
registered at the sensory level
■ Moray’s Selective Filter Model
– The selective filter blocks out most
information at the sensory level, but
some highly salient messages are so
powerful that they burst through the
filtering mechanism (e.g. your name)
 ■ Participant’s name gets through

Deficiencies
– Cocktail party phenomenon -a
partygoer can focus on a single
conversation in a noisy room

of ■ Participants can shadow meaningful

messages that switch from one ear to

Broadbent’s
another
■ Effects of practice on detecting information
in unattended ear
Model – You can be trained to detect in
unattended ear based on the meaning
of the message
Selective Attention Theories

■ Treisman’s Attenuation Model

– Three Stages
– We pre attentively analyze the physical
properties of a stimulus (stimuli with
target properties)
– We analyze whether a given stimulus has
a pattern, such as speech or music
– We sequentially evaluate the incoming
messages, assigning appropriate
meanings to the selected stimuli
messages
Selective Attention Theories
■ Deutsch and Deutsch’s Late Filter Model
– Placed the signal-blocking filter later in the process,
after sensory analysis and also after some perceptual
and conceptual analysis of input had taken place
– suggested that stimuli are filtered out only after they
have been analyzed for both their physical properties
and their meaning.
– This later filtering would allow people to recognize
information entering the unattended ear. For example,
they might recognize the sound of their own names or
a translation of attended input (for bilinguals).
■ Neisser’s Synthesis
– Two processes governing attention
– Pre-attentive processes (rapid, automatic, parallel)
– Attentive processes (controlled, occur later, serial)
Divided Attention

■ Attending to two different stimuli at the same

time, and respond to the multiple demands of
your surroundings.
■ type of simultaneous attention that allows us to
process different information sources and
successfully carry out multiple tasks at a time
■ How well people can divide their attention also
has to do with their intelligence
■ Interference - when a person has a hard time
attending to two stimuli at a time.
Theories of
Divided Attention
■ Capacity models of attention
– Posit that people have a fixed
amount of attention that they
can choose to allocate
according to what the task
requires.
– Two different kinds:
■ One model suggests
that there is one single
pool of attentional
resources that can be
divided freely, and
■ The other model
suggests that there are
multiple sources of
attention
STROOP
TASK: SAY
THE COLOR
OF EACH
WORD
Limitations of ■ People are much better at dividing their attention
when competing tasks are in different modalities.

Capacity ■ At least some attentional resources may be specific

to the modality (e.g., verbal or visual) in which a
Model task is presented.
– Ex. most people easily can listen to music and
concentrate on writing simultaneously.
– It is harder to listen to the news station and
concentrate on writing at the same time.
– The reason is that both are verbal tasks- The
words from the news interfere with the words
you are thinking about.
– Similarly, two visual tasks are more likely to
interfere with each other than are a visual
task coupled with an auditory one
Factors that Influence
Attention
■ Anxiety
– Being anxious, either by nature (trait-based anxiety) or by
situation (state-based anxiety), places constraints on attention
■ Arousal
– overall state of arousal affects attention as well.
– Being tired, drowsy, or drugged, which may limit attention.
– Being excited sometimes enhances attention.
■ Task difficulty
– Working on a task that is very difficult or novel for will need
more attentional resources than workinng on an easy or highly
familiar task.
– Task difficulty particularly influences performance during
divided attention.
■ Skills
– The more practiced and skilled you are in performing a task,
the more your attention is enhanced.
NEUROSCIENCE OF
ATTENTION
Brain and physiology
Neuroscience and Attention: A Network
Model
■ Three subfunctions of attention:
■ Alerting
– Being prepared to attend to some incoming
event, and maintaining this attention.
– The brain areas involved in alerting are the right
frontal and parietal cortexes as well as the locus
coeruleus.
– The neurotransmitter norepinephrine is involved
in the maintenance of alertness.
– If the alerting system does not work properly,
people develop symptoms of ADHD;
– Dysfunctions of the alerting system may develop
in old people as well.
Neuroscience and Attention:
A Network Model
■ Orienting
– The selection of stimuli to attend to.
– Needed when we perform a visual search.
– The orienting network develops during the first year of life.
– The brain areas involved in the orienting function are the superior
parietal lobe, the temporal parietal junction, the frontal eye fields,
and the superior colliculus.
– The modulating neurotransmitter for orienting is acetylcholine.
– Dysfunction within this system can be associated with autism.
■ Executive attention
– Includes processes for monitoring and resolving conflicts that arise
among internal processes.
– Include thoughts, feelings, and responses.
– The brain areas involved in this final and highest order of attentional
process are the anterior cingulate, lateral ventral, and prefrontal
cortex as well as the basal ganglia.
– The neurotransmitter most involved in the executive attention process
is dopamine.
– Dysfunction within this system is associated with Alzheimer’s
disease, borderline personality disorder, and schizophrenia.
Intelligence and Attention
■ Luria’s (1973) theory of intelligence
■ Assumes that intelligence consists of an assortment of
functional units that are the basis for specific actions
■ Planning, Attention, and Simultaneous–Successive
Process Model of Human Cognition (PASS)
■ Three distinct processing units and each is associated
with specific areas of the brain: arousal and attention,
simultaneous and successive processing, and planning
■ arousal and attention, is primarily attributed to the
brainstem, diencephalon, and medial cortical regions of
the brain.
■ The researchers suggest that arousal is an essential
antecedent to selective and divided attention.
Intelligence and
Attention
■ Inspection time
– The amount of time it takes you to inspect items and
make a decision about them
– Task requires concentrated bursts of focused attention.
– Shorter inspection times correlate with higher scores on
intelligence tests
■ Reaction Time
– the smart person is someone whose neural circuits
conduct information rapidly
– Participants with higher IQs are faster than participants
with lower IQs in their choice reaction time (CRT).
– These findings may be a function of increased central
nerve-conduction velocity, although at present this
proposal remains speculative
Habituation and Adaptation
■ Habituation
– Becoming accustomed to a stimulus so that we gradually pay
less and less attention to it.
– The processes involve no conscious effort.
– The relative stability and familiarity of the stimulus govern these
processes.
■ Dishabituation
– A change in a familiar stimulus prompts us to start noticing the
stimulus again. Both processes occur automatically.
– Any aspects of the stimulus that seem different or novel
(unfamiliar) either prompt dishabituation or make habituation
less likely to occur in the first Place
■ Sensory adaptation
– lessening of attention to a stimulus that is not subject to
conscious control.
– It occurs directly in the sense organ, not in the brain.
Habituation and
Adaptation
■ Two factors that influence habituation:
■ Internal variation
– Changes that occur within the stimuli
– Ex. background music contains more internal
variation (changing melodies, harmonies, and
rhythms) than does the steady drone of an air
conditioner.
■ Arousal
– Degree of physiological excitation, responsivity,
readiness for action, relative to a baseline.
– Often is measured in terms of heart rate, blood
pressure, electroencephalograph (EEG)
patterns, and other physiological signs.
Automatic and Controlled
Processes in Attention
■ Automatic processes
– Performed without conscious awareness
– Demand little or no effort or even intention.
– Three attributes characterize automatic processes:
■ concealed from consciousness
■ unintentional
■ consume few attentional resources.

■ Parallel processes
– Multiple automatic processes may occur at once, or at
least very quickly, and in no particular sequence.
■ Ex. You are able to read while at the same time
sharpening your pencil and scratching your leg with
your foot.
Automatic and Controlled Processes in
Attention
■ Controlled processes
– Accessible to conscious control and even require it.
– Occur sequentially, one step at a time. They take a relatively long
– time to execute, at least as compared with automatic processes

■ Automatization (Proceduralization)
– Tasks that start off as controlled processes eventually become automatic ones as a
result of practice
– However, when conditions change, the same activity may again require conscious
control.
■ Ex. When driving, if the roads become icy, you will likely need to pay attention to when
you need to brake or accelerate.
How Does
Automatization Occur?
■ Repeated practice of behavior
■ requires few or no cognitive resources, such as attention

■ Instance theory - suggests that automatization occurs

because we gradually accumulate knowledge about
specific responses to specific stimuli.
■ Ex. when a child first learns to add or subtract, he or she
applies a general procedure—counting—for handling
each pair of numbers.
■ Following repeated practice, the child gradually stores
knowledge about particular pairs of particular numbers.
■ Eventually, the child can retrieve from memory the
specific answers to specific combinations of numbers.
Practice Effect

■ The effects of practice on automatization show a negatively accelerated curve.

■ Early practice effects are great.
■ Later practice effects make less and less difference in the degree of automatization.
■ Automatic processes generally govern familiar, well-practiced as well as easy tasks.
■ Controlled processes govern relatively novel as well as difficult tasks.
■ highly automatized behaviors require little effort or conscious control, we often can
engage in multiple automatic behaviors.
■ We rarely can engage in more than one labor-intensive controlled behavior.
DEFICITS AND DISORDERS
IN THE ATTENTIONAL
PROCESS
When attention fails
Deficits in the
Attentional Process
■ Change Blindness-
inability to detect
changes in objects or
scenes that are being
viewed
■ Inattentional
Blindness- a
phenomenon in which
people are not able to
see things that are
actually there
Disorders in the
Attentional Process
■ Spatial neglect or hemi-neglect
– An attentional dysfunction in which
participants ignore the half of their visual
field that is contralateral to (on the
opposite side of) the hemisphere of the
brain that has a lesion.
– Caused mainly by unilateral lesions in the
parietal and frontal lobes, most often in
the right hemisphere.
– One way to test for neglect is to give
patients who are suspected of suffering
from neglect a sheet of paper with a
number of horizontal lines.
– Patients are then asked to bisect the
lines precisely in the middle of each.
– Patients with lesions in the right
hemisphere tend to bisect the lines to the
right of the midline.
– Patients with lesions in the left
hemisphere tend to bisect the lines to the
left of the midline
Disorders in the
Attentional Process
■ Attention deficit hyperactivity disorder (ADHD)
– Difficulty in focusing their attention in ways that enable them to
adapt in optimal ways to their environment
– The three primary symptoms are inattention, hyperactivity, and
impulsiveness.
– There are three main types: (a) hyperactive-impulsive, (b)
inattentive, and (c) a combination of hyperactive-impulsive and
inattentive behavior.
– Often treated with a combination of psychotherapy and drugs.
– Some of the drugs currently used to treat ADHD are Ritalin
(methylphenidate), Metadate
– Methylphenidate are stimulants while Strattera (atomoxetine) is not.
– Atomoxetine affects the neurotransmitter norepinephrine.
– The stimulants (methylphenidate), in contrast, affect the
neurotransmitter dopamine
END OF
LECTURE
Any Questions?