EEG COHERENCE AND SYNDROMES IN SCHIZOPHRENIA

Background Frith et al (1995) and others have hypothesised that disrup tions in the connection between left frontal and temporal areas of the brain are a central deficit in schizophrenia. In this paper we examin e whether such connectivity as assessed by EEG coherence is related to level of symptoms in patients with schizophrenia. Method For 73 patie nts with schizophrenia, assessments of the EEG coherence between front al and temporal regions were carried out under conditions of activatio n by a mathematical task, and between frontal and occipital regions wh en performing a visuo-spatial task. We then examined the relationship between these coherence measures and the reality distortion, disorgani sation and psychomotor poverty dimensions of symptomatology. Results O nly left frontal-temporal connectivity was found to have a significant negative relationship to symptomatology. This relationship was, howev er, specific to reality distortion rather than to symptoms of disorgan isation or psychomotor poverty, and may be more characteristic of male s than females. Conclusions Disruption of frontal temporal connectivit y appears to have a specific relationship to reality distortion sympto ms in schizophrenia.