Slide 31

At least as interesting as this posterior hyperactivation is an anterior deactivation, which seems at least in a preliminary analysis to be shared by normal, non-autistic brothers of people with autism.

Again comparing incongruent distractors against congruent distractors, normal subjects activated right frontal pole, while people with autism failed to activate this region and also deactivated rostral anterior cingulum. The sib group actually deactivated frontal pole, as well as the cingulate region.

There were slight differences in behavioural performance between groups, the autism and sib groups being marginally worse at the task than normal - so it isn't clear whether the frontal deactivation may be cause or consequence of behaviour. In either case, though, the result seems of interest.

This rostral region of the cingulum is an affective region that's normally deactivated when a more dorsal, cognitive subregion is engaged.

Dorsal cingulum may indeed have been active in this attentionally demanding task, though not significantly differentially active between the congruent and incongruent conditions.