In a recent post, the Eides (www.eideneurolearningblog.blogspot.com) wrote about a study showing that elementary school children look away from their questioner when given a difficult problem to solve (http://eideneurolearningblog.blogspot.com/2009/07/eye-contact-look-away-to-think-and.html#comments). When children were trained in gaze aversion, it helped their performance. When instructed to "look at me," their performance decreases. The theory is that looking away decreases "cognitive load" by removing extra environmental input from the attentional field.
Interestingly, the poorest performance occurred while looking at the examiner (over and above the decrease in performance from looking at a moving visual stimulus). As social beings, we're highly tuned to the facial expressions and gestures of others. So it's not surprising that looking at another person would be particularly distracting.
Children on the autistic spectrum are known for looking away from faces and eyes. What are we to conclude about them from this study, if anything?
Some researchers think spectrum kids look away from faces because they process faces differently than other kids. They note that spectrum kids show less activation in the fusiform face area (FFA) while looking at faces1. The FFA is particularly sensitive to faces, since most of us are face-reading experts, but they also activate in response to any visual stimuli in which a person has expertise. Car experts' FFAs activate for cars, but not for birds, while bird experts' FFAs activate for birds but not for cars2. Children on the spectrum process faces differently, some researchers argue, because from an early age, they do not look at faces as much as their peers3. As a result, they don't develop that expertise and their FFA does not wire properly to become sensitive to faces. That prevents them from taking in information by looking at faces.
Some researchers have disputed that assumption, I think convincingly. Dapretto found that spectrum and typically developing kids looked at the eyes for equal lengths of time, contradicting the assumption that children on the spectrum always look at faces less than their peers4. She used a fixation cross to cue spectrum kids to focus on the face and eyes, which studies showing less activation in the FFA did not do. The fixation cross overcame spectrum kids' usual tendency not to look at faces and eyes. If differences in methodology can remove gaze effects, then they're not a fundamental characteristic of autistic spectrum disorders. Furthermore, even at the most liberal thresholds, Dapretto didn't see any difference in FFA activation between kids on the spectrum and typically developing kids5. It doesn't look like face processing problems are the culprit here.
The gaze aversion studies suggest another possibility. What if children on the spectrum actually look away from faces because they are particularly sensitive to, and overwhelmed by, large amounts of stimuli from the environment? Many children on the spectrum are either over- or under-sensitive to sensory stimuli, so it would make sense. (Children who are over-sensitive are more obviously overwhelmed by stimuli from the environment, but it's possible that children appear undersensitive because they've developed the habit of tuning out stimuli so they don't become too overwhelming).
If children are just overwhelmed by large amounts of stimuli, they need not have a problem processing faces. Maybe faces are no more a problem for them than for their peers, but since they have a lower threshold of overwhelm, they have to look away more?
Maybe the fact that autistic spectrum kids look away more from faces, combined with the studies described by the Eides, supports the caetextia theory6. In other words, kids on the spectrum have difficulty shifting between attentional foci, and integrating memory and information from the environment into their thinking and decision-making. If taking in & integrating information from the environment is particularly a problem for spectrum kids, they'd probably be more likely to look away from faces than their peers.
I'd love to see research on this topic. For instance, it would be great to compare typically developing kids' and autistic spectrum kids' performance decrease when asked to look at the experimenter (vs. when asked to look at some other moving object).
Also--it'd be interesting to know how many people on the autistic spectrum have a hyperfocused attentional profile. There may be a connection here.
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1 Bolte, S., Feineis-Matthews, S., Prvulovic, D., Dierks, T. & Poustka, F. (2006). Facial
affect recognition training in autism: Can we animate the fusiform gyrus? Behavioral Neuroscience in the Public Domain, 120(1), 211-216
Wang, A.T., Dapretto, M., Hariri, A.R., Sigman, M., & Bookheimer, S.Y. (2004). Neural
correlates of facial affect processing in children and adolescents with autism spectrum disorder. Journal of the American Academy of Child & Adolescent Psychiatry, 43(4), 481-490.
Schultz, R.T. (2005). Developmental deficits in social perception in autism: The role of
the amygdala and the fusiform face area. International Journal of Developmental Neuroscience, 23(2-3), 125-141
2 Schultz, R.T., Grelotti D.J., Klin A., Kleinman J., Van der Gaag C., Marois R.,
Skudlarski P. (2003). The role of the fusiform face area in social cognition: Implications for the pathobiology of autism. Philosophical Transactions of the Royal Society of London—Series B: Biological Sciences 358(1430), 415-427
3 Schultz, R.T. (2005). Developmental deficits in social perception in autism: The role of
the amygdala and the fusiform face area. International Journal of Developmental Neuroscience, 23(2-3), 125-141
4 Dapretto, M., Davies, M.S., Pfeiffer, J.H., Scott, A.A., Sigman, M., Bookheimer, S.Y.,
Iacoboni, M. (2006): Understanding emotions in others: mirror neuron dysfunction in children with autism spectrum disorders. Nature Neuroscience 9(1): 28-30
5 As above.
6 www.caetextia.com
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