Broken Social Scene - Fire Eye'd Boy (WATCH on YouTube)
An interesting new study used eye-tracking methodology to compare how individuals with Williams syndrome ("hyper social") and autism ("hypo social") view pictures of social scenes containing people.
Broken Social Scene Perception1 (Riby & Hancock, 2008)
Williams syndrome (WS) is a rare genetic disorder that results from a deletion in the region q11.23 of chromosome 7. Individuals with Williams Syndrome have a characteristic facial appearance, severely impaired visuospatial skills, relative preservation of language skills (typically in concrete, practical vocabulary, as opposed to abstract vocabulary), and a highly social demeanor. In contrast, individuals with autism have notable impairments in social interaction abilities. Thus, these two developmental disorders have quite opposite effects on social behaviors, and comparative studies may illuminate many aspects of social cognition (Tager-Flusberg et al., 2006).
A number of previous studies have examined the patterns of eye gaze while participants with autism view pictures of human faces (e.g., Sasson et al., 2007), but no experiments to date have applied the same techniques to WS. Riby and Hancock (2008) tested 16 people with WS (ages 8-28, mean age 17.5 yrs) and 20 people with autism (ages 6-18 years, mean age 13 yrs). A control group of typically developing children and adults with low nonverbal scores (ages 8-28, mean age 17.5 yrs), and groups of age-controls were formed for comparison.
The participants viewed 20 pictures of social scenes and 5 filler photographs for 5 sec each while gaze was monitored with an eye tracker. Fixation "areas of interest" (AOI) were designated, and included face (eyes and mouth), body, and background. The results are illustrated below.
Fig. 1 (Riby & Hancock, 2008). Fixation duration as a function of group membership. Hotspots represent the relative amount of time spent fixating throughout the scene for each group (a) typically developing children, (b) autism and (c) WS.
There was a statistically significant interaction between AOI and group. The WS subjects viewed faces for a longer duration than did their respective controls. Specifically, the WS group spent more time viewing the eyes, but not the mouth. Conversely, as has been demonstrated in previous studies, the participants with autism spent significantly less time looking at faces (eyes in particular) than did their controls.
Whilst individuals with autism spent a significantly smaller proportion of time than typical fixating on characters’ eyes (17% of face gaze time), those with WS spent significantly longer than typical fixating on the same region (58% of face gaze time). Visual attention to the eyes may be implicated in other divergent abilities in face perception, such as the interpretation of gaze cues and expressions, where individuals with WS are more proficient than those with autism.The authors suggest that future research should focus on the causes of atypical social preferences in WS (e.g., differences in amygdala and prefrontal cortex function relative to controls).
Footnote
1 The authors are not responsible for that title, which is not meant to be offensive.
References
RIBY D, HANCOCK P. (2008). Viewing it differently: Social scene perception in Williams syndrome and Autism. Neuropsychologia, 46(11), 2855-2860. DOI: 10.1016/j.neuropsychologia.2008.05.003
The genetic disorder Williams syndrome (WS) is associated with a propulsion towards social stimuli and interactions with people. In contrast, the neuro-developmental disorder autism is characterised by social withdrawal and lack of interest in socially relevant information. Using eye-tracking techniques we investigate how individuals with these two neuro-developmental disorders associated with distinct social characteristics view scenes containing people. The way individuals with these disorders view social stimuli may impact upon successful social interactions and communication. Whilst individuals with autism spend less time than is typical viewing people and faces in static pictures of social interactions, the opposite is apparent for those with WS whereby exaggerated fixations are prevalent towards the eyes. The results suggest more attention should be drawn towards understanding the implications of atypical social preferences in WS, in the same way that attention has been drawn to the social deficits associated with autism.
Sasson N, Tsuchiya N, Hurley R, Couture SM, Penn DL, Adolphs R, Piven J. (2007). Orienting to social stimuli differentiates social cognitive impairments in autism and schizophrenia. Neuropsychologia 45:2580–2588.
Tager-Flusberg H, Plesa Skwerer D, Joseph RM. (2006). Model syndromes for investigating social cognitive and affective neuroscience: A comparsion of autism and Williams syndrome. Social, Cognitive and Affective Neuroscience 1:175–182.
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