Perruchet Effect

Discovered by psychologist Pierre Perruchet in a 1985 eyeblink conditioning experiment. Participants were exposed to a musical tone (conditioned stimulus) paired with an air-puff to the eye (unconditioned stimulus). The results revealed a double dissociation: as runs of paired trials increased, conditioned responses strengthened, while conscious expectancy decreased according to the gambler's fallacy. This demonstrated that automatic associative learning can operate independently of conscious expectation, challenging traditional conditioning theories.