UNILATERAL CONDITIONING OF AN ODOR AVERSION IN 6-DAY-OLD RAT PUPS

In young rats, several forms of olfactory memory can be functionally l ocalized to one side of the brain by restricting training stimuli to o ne naris and corresponding olfactory bulb. In this experiment, the ana lysis of lateralized olfactory learning in 6-day-old rat pups was exte nded by an evaluation of the consequences of aversive reinforcers in a unilateral olfactory conditioning paradigm. An olfactory aversion was conditioned by delivering a mild footshock to animals in the presence of a novel odor. Olfactory stimulation was confined to one naris and corresponding olfactory bulb by inserting a soft rubber plug into the opposite naris. This lateralization in processing resulted in unilater al memory for the odor aversion that was only expressed when the train ed naris was open during an odor preference test. The hypothesis that the hedonic value (or valence) component of conditioning is represente d in structures that are unilaterally accessed during training and tes ting is discussed.