Frontal cortex reactivity differentiates between schizophrenic subtypes: auditory ERP-evidence

To extend the hypothesis that late auditory EP shifts represent pathophysiologcial markers in schizophrenia.

Early negative (±100 μs) and late positive (>300 ms) auditory oddball and CNV responses are topographically compared in 3 medicated schizophrenic subtypes.

Only late cortical responses differentiate between paranoid, residual and disorganised schizophrenia. Core features of the deficit residual state encompass low-voltage N2P3 responses and missing central initial CNV components. Both paranoid and disorganised schizophrenics show a distinctive reactivity of the frontal cortex. Paranoid schizophrenia is characterized by an extensive frontal spread of the task-related P3 response. Disorganised schizophrenia shows a specifically increased frontal CNV component indicating a nonspecific arousal reaction.

Combinations of late auditory EP-patterns fairly fit with the cognitive/behavioral status observed in schizophrenia spectrum disorders.