This is how reading goes. A friend alerted me to a NY Times piece called What is Sleep? by Siri Hustvedt that led me to look up Morvan’s Syndrome (when you don’t sleep) and an Estonian-born researcher named Jaak Panksepp who is famous in the media (or was famous for ten minutes) for claiming that rats can laugh like humans. Of course, Panksepp is far more interesting than that. He does brain and behaviour research with an eye to investigating the differences between the ancient subcortical brain functions and the newer (in evolutionary terms) generalized gray matter we’ve grown on top of the old brain. Of course, there must be a difference. We trundled along, like most other animals, with those early brain parts for millions of years before we began to think and speak and make tools. All that is pretty new stuff, and much of what we feel and imagine and dream comes from much further back. This theorizing dovetails somewhat with a book called Origins of the Modern Mind by the Canadian neuropsychologist Merlin Donald. Donald’s book played a role in the way I read Don Quixote and formed part of the argument in my book The Enamoured Knight, especially in the last section “Night Thoughts of an Insomniac Reader.” But where Donald is interested in recent evolutionary developments (mimetic and representational functions and cognition), Panksepp is interested in basic emotional systems within the primitive brain. Deep in the older parts of our brain, we are quite similar to most other mammals. We separated from rats, for example, about 80 million years ago, but Panksepp finds certain rat brain structures that resemble parts of human brains (I always suspected this). He watches rats (he’s done lovely papers on the structure and function of play among rat cubs that yield suggestive ideas for autism, ADHD and early childhood socialization), for example, and that led to his notorious research on rats and laughter. His big book is Affective Neuroscience: The Foundations of Human and Animal Emotions, but there are several articles he wrote or co-wrote on the web if you can access them through a library database. Start with “The Seven Sins of Evolutionary Psychology” for a general roundup of current debates about brain evolution.