Home > Cognition, fMRI, Social > Social cognitive deficits in autism spectrum disorder

Social cognitive deficits in autism spectrum disorder

ResearchBlogging.org One of the hallmarks of Autism Spectrum Disorder (ASD) is an impairment in social cognitive skills. This manifests in individuals with ADS having trouble orienting their attention towards people. Accordingly, they also show deficits orienting their attention in response to social cues from others, such as eye gaze, head turns and pointing gestures.

Understanding the social cognitive impairments associated with ASD has been challenging in that studies set in naturalistic settings often reveal the deficit but lab experiments performed on computers don’t.

For example, some naturalistic studies have looked at home movies of infants and found that those later diagnosed with ASD showed less social orienting and were less responsive to cues from others to orient to objects. For example, if their mom was in the room, they would look at her a lot less and they’d also be less likely to respond when their mothers tried to direct their attention to a toy in the room by looking or pointing at it.

However, people with ASD have been shown to respond to non-naturalistic social cues in the lab. Social orienting has been frequently been tested by use of a variation on Michael Posner’s spatial cueing paradigm. This works as follows:

1. Participants are seated in front of a computer
2. A stimulus – a pair of eyes gazing to either side (or straight ahead) or arrows pointing to either side or neither – appears on the screen
3. Shortly after, a stimulus (the target object) appears to one side or the other, either on the side which the eyes or arrows were pointing towards or the opposite side.
4. Participants have to indicate which side the target object appeared on by pressing either a right or left button.
5. Performance on the task is assessed by measuring the amount of time it takes to participants to press the button indicating on which side the target appeared. Most participants, including ASD patients, are as quick with the gaze cue (the eyes) as with the arrow cue.

Posner cue paradigm

(The left side of the above figure shows a single trial (with “directional eyes”), in which participants first see a fixation cross, then one of four directional/non-directional stimuli, after which the target appears either on the same side indicated by the cue or the opposite side. Participants need to indicate which side a target stimulus appeared on by pushing a button. The right side shows the three other trial types (from top to bottom): neutral arrow, directional arrow, neutral eyes)

Past studies have shown that people orient faster to cued (like in the left side of the above figure) versus noncued locations, known as the facilitation effect. Previous studies using this task have produced inconsistent results, but most of them have shown ASD populations performing comparably to non-ASD populations.

In this study, researchers used the above-described cue task to examine the neural mechanisms underlying social orienting in ASD, with the hope that if there were no behavioral differences, neural activity might reveal that ASD individuals are performing the task differently. Other studies have shown that non-ASD populations treat social and non-social cue stimuli differently. It was hoped that neural activity revealed in this study would shed light on the discrepancies in behavioral results for ASD populations in lab versus computer settings.

Results
In terms of behavior, both the control and the ASD group showed quicker responses for gaze and arrow cues with no between group difference, which is consistent with previous lab studies.

However, neural activation patterns showed significant group differences. The control group showed greater activation for social vs. nonsocial cues in many different brain regions, with gaze (eyeball) cues eliciting increased activity in many frontoparietal areas, supporting the idea that neurotypical brains treat social stimuli different from non-social stimuli. The ASD group, on the other hand, showed much less difference in neural activation between social vs. non-social cues. Although these differences in neural activation are too numerous to cover here, one region of interest, superior temporal sulcus (STS), stood out. The STS has been shown to be associated with the perception of eye gaze and other work has suggested the region may be involved in understanding the intentions and mental states of others. In this study, ASD individuals showed decreased STS in the gaze cue condition (versus controls). This data suggests that the STS may not be sensitive toward the social significance of eye gaze in ASD individuals.

Implications
The authors point out that although ASD individuals don’t seem to rely on the same neural circuitry to perceive social cues such as eye gaze, they have found a way to use the low-level perceptual information available in social cues to adapt a strategy that allows them to discern that gaze direction conveys meaning about the environment. That being said, ASD individuals mostly don’t do this very well in more naturalistic environments. So, although this strategy might work in a scanner with “cartoon” eyes and where there are no environmental distractions, it’s unlikely that ASD individuals could adapt this strategy in a naturalistic environment. On the contrary, one could also frame these results from the perspective of the ASD individual; that is, given the non-naturalistic environment of the scanner, and the fact that the task demands were very simple and not dependent on social cognitive processing, why should non-ASD individuals treat the gaze vs. arrow stimuli differently? Why not just rely on low-level information and thus expend less cognitive energy? It’s a good example of the automaticity of social cognitive processes. Give humans a set of cartoon eyeballs to look at and they can’t help but process these as distinct from something non-social.

An additional take away from this paper is that even when one finds no behavioral differences between groups, there might be some interesting differences in neural activity worth exploring via fMRI or EEG.

References

Greene DJ, Colich N, Iacoboni M, Zaidel E, Bookheimer SY, & Dapretto M (2011). Atypical neural networks for social orienting in autism spectrum disorders. NeuroImage, 56 (1), 354-62 PMID: 21334443

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  1. Azkyroth
    May 7, 2011 at 4:02 pm | #1

    One note: a lot of people on the spectrum have difficulty processing what you might call “high level” stimuli from more than one sense at a time; thus, for example, they might find both listening to a person and maintaining eye contact to be overwhelming, and look away while paying attention to the words. The end result of this is that the assumption that someone is only paying attention to something they’re looking at 1) comes closest to holding for purely visual stimuli (looking away to “process” it might still occur, I suppose) and 2) is a needless, unfortunate, and almost cruel roadblock to full and productive participation in social, academic, and professional settings.

  2. DIfferent, Not Less
    May 8, 2011 at 8:50 am | #2

    This article is written in the “deficit” style of thinking about autism (it’s right there in the title). It’s a huge value judgement to call a difference in social orientation an “impairment.” It’s only an impairment to NT folks who don’t know what to do when others don’t respond to them as they expect.

    • dj
      May 8, 2011 at 10:45 am | #3

      I’m sorry if you find the term offensive – Perhaps you’re close to someone with ASD and you resent them being labeled with a term that carries negative connotations. If so, I can understand why you would be bothered.

      The word “deficit” that I used in the post wasn’t of my own invention; it’s standard lingo in the research trade.

      If I understand you correctly, you’ve suggested that saying ASDs perform less well than NTs in the area of social communication is to make a value judgment.

      If that’s the case, then I’d have to say we disagree.

      As we live in a world where social communication skills are vital to full participation in the society at large, the ability to attend to and process information from faces, including making eye contact, responding to emotional displays, recognizing faces, and following attentional cues, is quite important. To the extent that an individual presents a “different” (lower) level of competency in terms of these skills, it’s logical to think of the difference as a liability.

      This isn’t to say that the social cognitive profile of ASDs is wrong, incorrect or “bad” in some absolute sense, but only to say that relative to the cultural practices of modern homo sapiens, one will probably do less well if they don’t possess “normal” levels of social cognitive facility.

      From the perspective of scientists communicating autism-related research to the public and their peers, to say that ASDs perform “differently” in the domain of social communication from NTs lacks specificity. Hence, you see terms such as “deficit’ or “impairment,” which are references to domain-specific under performance compared to the larger population. The terms are not meant to suggest anything beyond that.

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