Objectives: In autism research, psychosocial deficits have been related to atypical eyetracking to faces and impaired emotion recognition (Pelphrey et al., 2002). We examined these measures in Primary AgCC, to see if they would show similarity to what has been found in autism, specifically impaired emotion recognition and reduced visual attention to the eyes in faces.
Methods: Nine adults with Primary AgCC and 9 neurotypical controls completed 4 tasks with the Ekman emotional faces: emotion recognition of upright faces and inverted faces, gender naming, and passive viewing. Participants were assessed for accuracy on the three recognition tasks. High-resolution eye-movement data collected throughout were analyzed according to examiner-designated facial regions of interest for absolute number of fixations and proportion of trial time fixating each ROI.
Results: The AgCC group was less accurate than controls in naming all emotions except happiness in upright faces. Naming of fear and anger was significantly impaired relative to controls. For upright faces, the AgCC group had smaller fractional dwell times and fewer fixations in the eye regions, and larger fractional dwell times and more fixations in the nose and mouth regions, compared to controls. Distribution of fixations across trial time indicates that control subjects generally fixated the eyes earlier in the trial than did AgCC subjects.
The AgCC group exhibited an inversion effect for emotion recognition, with a greater decline in performance than controls on happy, neutral and fearful inversions. Group difference was only significant for fearful faces. For inverted faces, fractional dwell times and number of fixations did not differ between groups.
AgCC subjects did not differ from controls in accuracy of gender identification, nor did they have significant differences in eye-tracking patterns during gender judgment. On the passive viewing task, the AgCC group exhibited a non-significant tendency toward lower fractional dwell time and fewer fixations in the eye regions.
Conclusions: Primary AgCC and autism share impairments in facial emotion recognition, which may be secondary to abnormal fixations to the features of faces. Specifically, participants with AgCC made fewer fixations to the eye region, with variable increases to mouth and nose regions of faces. These fixation abnormalities were relatively selective to emotion judgments of faces, and were associated with impaired recognition of emotion, especially fear and anger. These findings provide additional support for the connectivity hypothesis of social deficits in autism.