When I was still at Harvard, I was in constant contact with Alden Spencer, in part because I was eager for him to come to Harvard – he wanted to leave Oregon – and also because we had formulated a parallel strategy. He had carried out in the spinal cord experiments dealing with habituation, actual behavior habituation. And he wasn't able to reduce it to monosynaptic level, but nonetheless was able to see changes in synaptic strength, and we realized that a cellular approach was going to be extremely productive to studying learning and memory. So we wrote a review together for Physiological Reviews that came out in the early 1960s called “Cellular Neurophysiological Approaches in the Study of Learning” which really encouraged people who were cellular physiologists to get interested in behavior and learning. And we spelled out a number of strategies, including analogues of learning, but pointed out that the real challenge was to explore real instances of learning, and indicated how this might be done.

So we got a great deal of pleasure doing this. We learned a great deal from doing it, and I think the review was quite influential. And it started a trend in my own thinking of periodically writing reviews, which led to my later writing, the Cellular Basis of Behavior, and then getting inspired to do a textbook of neural science. And one of the things that we did at Columbia, once we got there, was to take the syllabus that we had at NYU, expand it, make it even better, include illustrations, and after a while we said, this is too good for just Columbia students. We should make a book out of it. We called it modestly Principles of Neural Science. And did extremely well. It's now in its fifth edition, and it's often considered the standard textbook in the field. It's gotten two awards, and we're looking forward to doing the sixth edition.