Prepulse inhibition (PPI) refers to the suppression of the startle reflex that occurs when an intense startling stimulus is preceded by a weaker ‘prepulse’ stimulus. PPI is considered a measure of sensorimotor gating, automatic inhibitory regulation of sensory input and/or motor response that allows for an undisturbed processing of relatively weak sensory events. Gating deficits are considered to be a possible neurobiological mechanism mediating cognitive abnormalities in schizophrenia and some other disorders (Braff et al., 2001). PPI is considered one of the potential endophenotypes for schizophrenia (Light et al., 2012).
