Olfactory bulb ablation or nerve section and behavior of pigeons in nonolfactory learning

Abstract

The possible significance of the primary olfactory system for behavior that does not involve olfaction was examined in a visual learning experiment with pigeons. Four groups were trained, one with bilateral section of the olfactory nerve, one with bilateral destruction of the olfactory bulb, one with an equivalent amount of damage on the hyperstriatal surface bilaterally, and one with anesthesia only. The final task required pecking the left of two keys when both keys were lighted with color 1 and pecking the right when both were lighted with color 2. Training was done in several stages which involved learning to eat from the food hopper in the training box, learning to peck one key while it was lighted with the first color, transferring pecking to the other key, and finally learning the complete task. The two groups with damage in the olfactory pathway were significantly slower in learning to eat from the hopper, in learning to peck the first key, and in transferring pecking to the second key. It is suggested that the olfactory system participates in some way in general limbic system functions.