Drug effects on sucessive discrimination learning in young chickens.

Chicks were trained to avoid pecking either a red or a blue bead in a one-trial avoidance task by coating one bead with methy anthranilate. They avoided the aversant bead on retention tests 10 to 180 min or 24 hr after learning, but not the neutral bead. Intracranial administration of ouabain or cycloheximide (CXM) 5 min before learning resulted in decay in retention after 10 and 30 min respectively following learning, discrimination being effective prior to those times. In a second experiment, chicks were trained on three physically distinct beads, two of which were made aversive during the learning period, the training trials separated by an hour. Saline-treated chickens retained memory of both aversive beads on retention trials 180 min later. CXM- and ouabain-treated chickens showed loss of memory for the bead associated with the drug but showed retention of the task which was not associated with the drug.