Insomniacs were found to have compromised perception of
facial expressions. Through eye movement examinations,
here we test the hypothesis that this effect is due to impaired
visual attention functions for retrieving diagnostic features in
facial expression judgments. 23 individuals with insomnia
symptoms and 23 non-insomniac controls completed a task to
categorize happy, sad, fearful, and angry faces. The
insomniacs were less accurate to recognize angry faces and
made more “fearful” mistakes than controls. A hidden
Markov modeling approach for eye movement data analysis
revealed that when recognizing angry faces, more insomniacs
adopted an eye movement pattern focusing on the mouth
while more controls adopted a pattern attending to both the
eyes and the mouth. This result is consistent with previous
findings that the primary diagnostic feature for recognizing
angry faces is the eyes suggesting that impaired information
selection through visual attention control may account for the
compromised emotion perception in insomniac individuals.