Prepulse inhibition of perceived stimulus intensity: paradigm assessment.

In 1939, Helen Peak reported that the presentation of paired acoustic stimuli, separated by 177ms, resulted in a 25% reduction in the perceived intensity of the second stimulus. After 65 years, this form of prepulse inhibition of perceived stimulus intensity (PPIPSI) remains relatively less developed, compared to technically and analytically complex "gating" measures, e.g.

Prestimulus modification of the startle reflex: relationship to personality and physiological markers of dopamine function.

Prepulse inhibition (PPI), a measure of sensorimotor gating, is regulated by dopamine (DA) in rodents. We examined the relationship of PPI in humans to putative markers of brain DA function: (1) novelty seeking (NS; Cloninger's Tridimensional Personality Questionnaire (TPQ)), which is associated with specific DA receptor subtypes, and is reduced in Parkinson's Disease; (2) blink rate, which is increased in primates by DA agonists, and is reduced in Parkinson's Disease. PPI, TPQ and blink rate were measured in 79 normal adult males.