Brain evoked potential in schizophrenic patients
Kubiszewski, M.; Hein-Antonik, K.; Maciejowski, A.; Kiejna, A.; Sobieszczańska-Lampika, M.
Psychiatria Polska 27(4): 407-422
1993
ISSN/ISBN: 0033-2674 PMID: 8416001 Document Number: 410050
The authors reviewed the literature on evoked potentials in mentally ill patients, with particular emphasis on schizphreniacs. The commonly observed abnormalities were as follows: 1) higher SEPs amplitudes with less waveshape variability during first 100 ms in non-depressed chronic, paranoid or undifferentiated patients with florid psychotic symptoms; normal SEPs amplitudes in acute or latent schizophrenics and in chronic depressed schizophrenics but without florid psychotic symptoms; 2) reduced SEPs and VEPs amplitude recovery and faster latency recovery; 3) reduced AEPs amplitude and latency; 4) greater VEPs waveshape variability and tendency to be "reducers" in hallucinating patients; reduced amplitude and latency recovery; prolonged latencies in patients with positive family history (schizophrenia or affective disorders in close relatives); prolonged N2 latency in motor responses to "easy" and "difficult" stimuli; reduced activity of "late potentials"; 5) greater waveshape variability in all modalities in chronic schizophrenics, abnormal P300 (reduced amplitude, lack of P300 or negative "effect of uncertainty") and abnormal CNV (less "readiness" potential, prolonged negativity with motor responses).