  Anatomical and functional brain studies have converged to the hypothesis that
Autism Spectrum Disorders (ASD) are associated with atypical connectivity.
Using a modified resting-state paradigm to drive subjects' attention, we
provide evidence of a very marked interaction between ASD brain functional
connectivity and cognitive state. We show that functional connectivity changes
in opposite ways in ASD and typicals as attention shifts from external world
towards one's body generated information. Furthermore, ASD subject alter more
markedly than typicals their connectivity across cognitive states. Using
differences in brain connectivity across conditions, we classified ASD subjects
at a performance around 80% while classification based on the connectivity
patterns in any given cognitive state were close to chance. Connectivity
between the Anterior Insula and dorsal-anterior Cingulate Cortex showed the
highest classification accuracy and its strength increased with ASD severity.
These results pave the path for diagnosis of mental pathologies based on
functional brain networks obtained from a library of mental states.
