WITHIN-EVENT LEARNING DURING FILIAL IMPRINTING

Newly hatched domestic chicks (Gallus gallus domesticus) that have rec eived a period of exposure to a visual stimulus (V1) approach V1 in pr eference to a novel stimulus (V2). The learning process that underlies such changes in chicks' behavior is known as filial imprinting. Under natural conditions, and in laboratory studies, V1 is often accompanie d by an auditory stimulus, the maternal call of a hen (Al). Experiment s la and Ib demonstrated that simultaneous exposure to V1 and Al poten tiated chicks' preference for V1 in a test in which Al was absent. Sub sequent experiments revealed that additional exposure to Al after (Exp eriment 2) or before (Experiment 3) exposure to the V1A1 compound redu ced the preference for V1. These findings suggest that the potentiatio n of visual imprinting is a product of within-event learning that is u ndermined when one element of the compound is presented in isolation.