Different psychopathological models and quantified EEG in schizophrenia

Background. This study compared the ability of two different models of psyc hopathology in schizophrenia to account for findings in the quantified elec troencephalogram (qEEG) recorded from midline sites in a group of 40 subjec ts with schizophrenia. The first model was based on the positive and negati ve syndrome dichotomy, the second was a tripartite model that resembled Lid dle's syndromes of psychomotor poverty, disorganization and reality distort ion(Liddle, 1987a). Methods. A group of 40 subjects with predominantly chronic schizophrenia wa s assessed with the Positive and Negative Syndrome Scale (PANSS) prior to t he acquisition of their quantified electroencephalogram. The relationship b etween EEG data and symptomatology was explored, initially with the PANSS p ositive and negative subscales and then with a tripartite model derived fro m a principal component analysis of the 14 positive and negative subscale i tems. Results, The tripartite syndrome model showed a greater concordance with th e qEEG of the subjects than the dichotomous model. 'Psychomotor poverty' wa s significantly positively correlated with both delta and beta power and 'r eality distortion' was significantly positively correlated with alpha-2 pow er. No significant correlations between the positive and negative syndrome dichotomy and the qEEG were observed. Conclusions. This study lends support to the factor analysis of psychopatho logy, and specifically the tripartite syndrome model of schizophrenia, as a step in explicating the biological dimensions of the disorder.