| Abstract: | Determined whether a deviation from normal amplitude in the evoked potential in response to attention directed to a stimulus would occur in 10 undergraduates with high scores on a measure of physical anhedonia (AN) and 9 undergraduates with a high score on a measure of perceptual aberration (PA). Ss were compared with 10 control undergraduates and 7 schizophrenics (mean age 25.6 yrs). Previous studies have shown low amplitudes for schizophrenics. Somatosensory evoked potentials (SEPs) were recorded from 5 scalp locations while Ss counted stimuli to 1 of 4 randomly stimulated fingers; SEPs to counted stimuli contained the attention-related late positive wave (P400). P400 amplitudes of AN Ss were lower than those of normal controls, whereas P400 amplitudes of PA Ss and their matched controls did not differ. P400 amplitudes of AN Ss did not differ significantly from those of schizophrenics, although AN means were somewhat higher. P400 amplitude may provide information that is different from the associated behavioral response and a more sensitive indication of central mechanism dysfunction. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
