1. Kenet T, Orekhova EV, Bharadwaj H, Shetty NR, Israeli E, Lee AK, Agam Y, Joseph RM, Hamalainen MS, Manoach DS. {{Disconnectivity of the cortical ocular motor control network in autism spectrum disorders}}. {Neuroimage};2012 (Mar 11)
Response inhibition, or the suppression of prepotent but contextually inappropriate behaviors, is essential to adaptive, flexible responding. Individuals with autism spectrum disorders (ASD) consistently show deficient response inhibition during antisaccades. In our prior functional MRI study, impaired antisaccade performance was accompanied by reduced functional connectivity between the frontal eye field (FEF) and dorsal anterior cingulate cortex (dACC), regions critical to volitional ocular motor control. Here we employed magnetoencephalography (MEG) to examine the spectral characteristics of this reduced connectivity. We focused on coherence between FEF and dACC during the preparatory period of antisaccade and prosaccade trials, which occurs after the presentation of the task cue and before the imperative stimulus. We found significant group differences in alpha band mediated coherence. Specifically, neurotypical participants showed significant alpha band coherence between the right inferior FEF and right dACC and between the left superior FEF and bilateral dACC across antisaccade, prosaccade, and fixation conditions. Relative to the neurotypical group, ASD participants showed reduced coherence between these regions in all three conditions. Moreover, while neurotypical participants showed increased coherence between the right inferior FEF and the right dACC in preparation for an antisaccade compared to a prosaccade or fixation, ASD participants failed to show a similar increase in preparation for the more demanding antisaccade. These findings demonstrate reduced long-range functional connectivity in ASD, specifically in the alpha band. The failure in the ASD group to increase alpha band coherence with increasing task demand may reflect deficient top-down recruitment of additional neural resources in preparation to perform a difficult task.
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2. Poljac E, Yeung N. {{Cognitive Control of Intentions for Voluntary Actions in Individuals With a High Level of Autistic Traits}}. {J Autism Dev Disord};2012 (Mar 21)
Impairments in cognitive control generating deviant adaptive cognition have been proposed to account for the strong preference for repetitive behavior in autism. We examined if this preference reflects intentional deficits rather than problems in task execution in the broader autism phenotype using the Autism-Spectrum Quotient (AQ). Participants chose between two tasks differing in their relative strength by indicating first their voluntary task choice and then responding to the subsequently presented stimulus. We observed a stronger repetition bias for the harder task in high AQ participants, with no other differences between the two groups. These findings indicate that the interference between competing tasks significantly contributes to repetitive behavior in autism by modulating the formation of task intentions when choosing tasks voluntarily.
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3. Reaven J, Blakeley-Smith A, Culhane-Shelburne K, Hepburn S. {{Group cognitive behavior therapy for children with high-functioning autism spectrum disorders and anxiety: a randomized trial}}. {J Child Psychol Psychiatry};2012 (Apr);53(4):410-419.
BACKGROUND: Children with high-functioning autism spectrum disorders (ASD) are at high risk for developing significant anxiety. Anxiety can adversely impact functioning across school, home and community environments. Cognitive behavioral therapies (CBT) are frequently used with success for children with anxiety symptoms. Modified CBT interventions for anxiety in children with ASD have also yielded promising results. METHODS: Fifty children with high-functioning ASD and anxiety were randomizedto group CBT or treatment-as-usual (TAU) for 12 weeks. Independent clinical evaluators, blind to condition, completed structured interviews (Anxiety Disorders Interview Schedule – Parent Version;ADIS-P) pre- and post-intervention condition. RESULTS: Forty-seven children completed either the CBT or TAU condition. Results indicated markedly better outcomes for the CBT group. Significant differences by group were noted in Clinician Severity Ratings, diagnostic status, and clinician ratings of global improvement. In the intent-to-treat sample, 10 of 20 children (50%) in the CBT group had a clinically meaningful positive treatment response, compared to 2 of 23 children (8.7%) in the TAU group. CONCLUSIONS: Initial results from this randomized, designed treatment study suggest that agroup CBT intervention specifically developed for children with ASD may be effective in decreasing anxiety. Limitations of this study include small sample size, lack of an attention control group, and use of outcome measures normed with typically developing children
4. Russell-Smith SN, Maybery MT, Bayliss DM, Sng AA. {{Support for a Link Between the Local Processing Bias and Social Deficits in Autism: An Investigation of Embedded Figures Test Performance in Non-Clinical Individuals}}. {J Autism Dev Disord};2012 (Mar 21)
The aim of this investigation was to explore the degree to which specific subsets of autistic-like traits relate to performance on the Embedded Figures Test (Witkin et al. in A manual for the embedded figures test. Consulting Psychologists Press, Palo Alto, CA, 1971). In the first group-based investigation with this focus, students were selected for their extreme scores (either high or low) on each of the ‘Social Skills’ and ‘Details/Patterns’ factors of the Autism Spectrum Quotient (Baron-Cohen et al. in J Austim Dev Disord 31:5-17, 2001). The resulting 2 x 2 factorial design permitted examination of the degree to which the social and non-social autistic-like traits separately relate to EFT performance. Surprisingly, in two studies, superior EFT performance was found to relate only to greater social difficulty, suggesting that the local processing bias in autism may be linked specifically to the social deficits.
