ATTENTIONAL MODULATION OF STARTLE IN PSYCHOSIS-PRONE COLLEGE-STUDENTS

Attentional modulation of startle eyeblink was studied in college stud ents putatively at risk for psychosis and in normal controls. At-risk subjects had extreme scores on scales for either anhedonia or perceptu al aberration-magical thinking (per-mags). Subjects were presented wit h to-be-attended and to-be-ignored tones; white noise startle probes w ere presented at lead intervals of 60, 120, 240, or 2,000 ms following the onset of attended and ignored tones and during intertone interval s. Controls showed greater inhibition of startle blink at 120 ms and g reater facilitation at 2,000 ms during to-be-attended than to-be-ignor ed tone, demonstrating attentional modulation of prepulse inhibition a nd facilitation. Both at-risk groups showed normal overall levels of e arly inhibition and late facilitation. However, per-mags failed to sho w attentional modulation of either inhibition at 120 ms or facilitatio n at 2,000 ms; anhedonics showed no modulation of inhibition and modul ation of facilitation was delayed in development. The results for the per-mags are strikingly similar to those observed in schizophrenic pat ients and suggest that these deficits index a trait-linked vulnerabili ty to disorders in the schizophrenic spectrum.