Abstract:
It is theorized that the implicit learning impairments seen in persons with ASD may be due to a more general underlying neural dysfunction evidenced by diminished activation in the basal ganglia, specifically the caudate nucleus, and diminished communication between areas of the brain in persons with ASD, specifically the caudate and medial temporal cortex. This study examined the relationship between implicit learning deficits in individuals with ASD and parents of persons with ASD and associated differences in brain activation. Twelve high-functioning children and adolescents with ASD and 17 age and verbal ability matched typically developing controls, 10 parents of participants with ASD, and 9 parents of typically developing participants completed an artificial grammar learning task while in an fMRI scanner. Behaviorally, participants with ASD showed significantly less grammar learning than typically developing participants. Additionally, parents of participants with ASD showed significantly less grammar learning than parents of typically developing participants. Activation analyses contrasting the neural response to grammatical versus nongrammatical stimuli revealed less activation in the areas of the anterior cingulate and caudate for participants with ASD compared to typically developing participants. Similar differences in these areas were also found in the parent groups. Results indicated that diminished activation in the caudate nucleus and cingulate cortex may underlie differences in implicit learning.
