Who's in Charge? by Michael Gazzaniga (he's famous for the early split brain studies, finding some of the ways the two hemispheres differ) is a pretty light read on current neuroscience, with the angle of looking at the idea of free will and what it means for personal responsibility and law. He covers some of his own findings, in particular around the left brain 'interpreter' which appears to be very good at making up stories to fit the apparent evidence.
While Gazzaniga lays out the strict reductionist/determinist viewpoint very effectively, he backs away from that outlook, and describes interlocking, complementary systems of upward and downward causality. He quotes a computer analogy from David Krakauer that makes good sense to me:
We do not program at the level of electrons, Micro B, but at a level of a higher effective theory, Macro A (for example, Lisp programming) that is then compiled down, without loss of information, into the microscopic physics. Thus, A causes B. Of course, A is physically made from B, and all the steps of the compilation are just B with B physics. But from our perspective, we can view some collective B behavior in terms of A processes. (p. 139)Moving over to the world of the brain, he takes a shot at the importance put on Libet's findings of brain activity preceding conscious awareness of movement:
What difference does it make if brain activity goes on before we are consciously aware of something? Consciousness is its own abstraction on its own time scale and that time scale is current with respect to it. Thus, Libet's thinking is not correct. That is not where the action is, any more than a transistor is where the software action is. (p. 141)He goes on to investigate the idea of the social mind - how our behavior is shaped and constrained by the actions of others, some directly and some more indirect via cultural norms. This is a whole other emergent level of causation that the reductionist viewpoint cannot really describe.
The last portion is about the legal aspects, and here I was a bit surprised that he did not reference David Eagleman since that his a big area of his focus, and overall it felt a bit too light a review to really do it justice.
But overall I enjoyed the book, agreed in general with his scientific and philosophical take on things.
Here's a review from WSJ online by Raymond Tallis.