Face recognition in Asperger syndrome: a study on EEG spectral power changes.

EEG reactions in emotional face recognition were studied in five participants with Asperger syndrome (AS) and seven control subjects. Control subjects showed a spectral power increase following the stimulus onset in two time-frequency intervals-(1) 150-300ms in the 1-16Hz frequency range and (2) 300-650ms in the 1-8Hz range. Also, alpha/beta desynchronization occurred 400-1000ms after the stimulus onset with maximal amplitude in the posterior region. Theta synchronization (4-8Hz) was weaker in the AS group than in the control group, but beta2 desynchronization was stronger in the AS group. The results were interpreted in terms of automatic and voluntary control of perception.