Psychophysiological measures of (dis)inhibition as liability indicators for schizophrenia

Abstract

Two psychophysiological measures, poor suppression of midlatency auditory-evoked responses in a paired stimulus paradigm and ocular motor abnormalities, may index genetic liability for schizophrenia. An important feature of these measures is that both patients and their nonpsychotic relatives exhibit basically the same performance. These measures may be successful endophenotypes for schizophrenia because they assess poor response inhibition associated with dysfunction of dorsolateral prefrontal cortex circuitry. Data bearing on this hypothesis are reviewed, and it is posited that assessment of the auditory-evoked gamma band response and saccade measures of inhibitory abilities are the most valid behavioral measures of schizophrenia's neuropathological correlates. The extant data suggest that psychophysiological studies of schizophrenia can provide consistent and theoretically meaningful information for localizing neuropathology and for assessing the genetics of this complex disorder.

Alpha-7 nicotinic receptor agonists: potential new candidates for the treatment of schizophrenia

“…Genetics of the P50 gating deficit and the alpha 7 nicotinic receptor gene Because many relatives of people with schizophrenia have poor P50 suppression (Siegal et al 1984;Waldo et al 1991Clementz 1998;Ross et al 1999), this deficiency is possibly a genetically determined trait (Waldo et al 1991). An initial genome scan using poor P50 suppression as a phenotype gave only suggestive results at several chromosomes (Coon et al 1993).…”

Test–retest reliability of P50, N100 and P200 auditory sensory gating in healthy subjects

“…Deficits in inhibitory functions under various experimental conditions are often found in schizophrenic patients and may be considered a core feature of the schizophrenic pathophysiology (Boutros et al, 2004;Braff et al, 2001;Clementz, 1998;Curtis et al, 2001;Mathalon et al, 2002;Moritz et al, 2001;Poole et al, 1999). A disturbed inhibitory function of the brain to irrelevant sensory input, i.e.…”

Saccadic inhibition among schizotypal personality disorder subjects

“…One means for investigating the relationship between SPD and schizophrenia is using laboratory measures of purported schizophrenia risk~Cadenhead, Light, Geyer, & Braff, 2000;Clementz, 1998!. The schizophrenia spectrum disorders are hypothesized to share a neurobiological etiology~Kendler et al, 1995!.…”