Schneider's first rank symptoms and continuous performance disturbance as indices of dysconnectivity of left- and right-hemispheric components of language in schizophrenia.

Background: Here we investigate pathophysiological dimensions (language disturbance, negative symptoms, lateralisation and the continuous performance test) in relation to ICD-10 and DSM-IV concepts of diagnosis.

Methods: A total of 32 consecutive psychotic patients with at least one Schneider's first rank symptom (SFRS), 15 depressed patients without SFRS and 17 normal volunteers were assessed with the Clinical Language Disorder Rating Scale (CLANG), SFRS, "pure defect" Huber's basic symptoms (HBS), handedness (Annett's pegboard task), and the A-X Continuous Performance Test (AX-CPT).

Results: CLANG total score (an index of severity of language disorder) was correlated with the severity of SFRS, a higher leftward shift of handedness, and poorer performance on AX-CPT.