Semantic decisions in adolescents with autism spectrum disorders - functional magnetic resonance imaging study

Goal: to assess fMRI activation during semantic tasks in adolescents with ASD.

Material: 44 right-handed male adolescents aged 12-19 (mean 14.3 ± 2.0) - 31 with autism spectrum disorders who met DSM-IV-TR criteria for Asperger's syndrome and 13 neurotypical adolescents matched according to age and handiness. Method: Functional testing (fMRI) was performed during semantic decisions tasks and phonological decisions in three categories of tasks: concrete nouns, verbs with plural meanings, words describing states of mind, as a control condition. Statistical analyzes were performed at the level of p <0.05 with FWE (family-wise error) correction and p <0.001.

Results: lower BOLD signal was demonstrated in many brain areas including precuneus, posterior cingulate gyrus, angular gyrus, parahippocampal gyrus, regardless of task category and processing method in the ASD group. The smallest differences in semantic processing were found for concrete nouns and the greatest ones for words describing states of mind.

Conclusions: the presence of different activation patterns in the ASD group suggests that far more than just the areas traditionally attributed to language processing, are involved in semantic deficits in ASD.