Effects of learning on cytochrome oxidase activity in cuttlefish brain.

Using cytochrome oxidase (CO) histochemistry, the effects of instrumental conditioning in cuttlefish central nervous system were examined. The posterior superior frontal lobe showed an increase of CO labelling just after training, whereas the anterior superior frontal lobe exhibited a decrease of CO staining 24 h post-training. These findings provide the first metabolic evidence for the involvement of the superior frontal lobe in learning and memory processes in cuttlefish. It is concluded that CO histochemistry can be used to provide a functional mapping of learning-induced plasticity in cuttlefish brain.