Abstract:
Background: The Poffenberger task is a useful paradigm that measures the interhemispheric transfer time (IHTT) across the corpus callosum. Past research has demonstrated that the right to left transfer is faster in typically developing individuals compared to a left to right transfer. Numerous studies have found that the corpus callosum is structurally smaller and atypical in individuals with Autistic spectrum disorder (ASD) but whether this is associated with changes in interhemispheric time transfer in adult individuals with ASD is relatively unknown. Method: The current study used a Poffenberger paradigm in combination with electro- encephalography (EEG) to measure IHTT between individuals with ASD and typically developing controls. The IHTT in each direction was estimated by comparing the latencies of P100 and N170 components in hemispheres contralateral and ipsilateral to lateralised visual stimulation. Results: Both groups demonstrated faster right to left transfer of information compared to the left to right transmission. Individuals with ASD exhibited faster IHTT latencies overall for the P100 and N170 components compared to matched typically developing controls. More importantly, these results demonstrate that the ASD group exhibited faster transfer in both directions com- pared to matched typically developing controls. Conclusion: These findings suggest hyper-connectivity of local networks in parietal and occipital regions of the corpus callosum in ASD and may have implications in how information is integrated between hemispheres in ASD.
