Saccadic movements using eye-tracking technology in individuals with autism spectrum disorders: pilot study.

OBJECTIVE To verify differences in the visual scanning strategies between pervasive developmental disorders (PDD) and controls when they are observing social and non-social pictures. METHOD PDD group (PDDG) comprised by 10 non-retarded subjects (age from 4 to 41) and age-matched control group (CG). Nine social pictures with human beings (including two pictures of cat mask), and 3 nonsocial pictures of objects were presented for 5 seconds. Saccadic movements and fixation were recorded with equipment EyeGaze (LC Technologies Inc.). RESULTS PDDG (mean=292.73, SE=67.62) presented longer duration of saccadic movements for social pictures compared to CG (mean=136.06, SE=14.01) (p=0.04). The CG showed a higher number of fixations in the picture 7 (a women using a cat mask, with the eyes erased) (CG: mean=3.40; PDDG: mean=1.80; p=0.007). CONCLUSION The results suggest differences in strategies that PDD explore human picture. Moreover, these strategies seem not to be affected by the lack of expected part of the face (the eyes).