The Body Has a Mind of Its Own

Someone in one of my meditation groups recently recommended this The Body Has a Mind of Its Own.  Seems meditation kindles an interest in brain science for other folks as well.  This pop science book doesn't have anything to say about the science of meditation (though it seems that mentioning the subject is now necessary when discussing the brain -- Koch also felt the need).  Instead, it focuses on the various ways the body is represented in the brain.  While the idea that the brain represents anything at all is, I think, a philosophically bankrupt one, no one can deny that there are a number of cortical maps that appear to us, as third party investigators, to represent sensation or movement in various parts of the body.  That is to say that there are cortical areas that have a constant 1-to-1 correspondence between their activity and a stimulus.  Moreover, if a stimulus applied to, say, my left big toe, causes activity in a particular region of the brain, then a stimulus applied to my left index toe causes activity in a neighboring cortical region.  In other words, what we mean by "a map" in the brain is a topology preserving correspondence (I think this is a homeomorphism, but I ain't no mathematician) between a set of stimuli ordered according to some metric (often just regular cartesian space) and cortical activity (ordered, again, according to regular cartesian space, though perhaps accounting for the way the brain is basically a folded up surface.  Nearby stuff, as measured by one metric, maps to nearby stuff, as measured by the other metric.

Because this is a pop science book that trusts no reader as capable of looking at a footnote or understanding an analogy that does not involve either NASCAR or their family pet, their definition of "map" is limited to one sentence.  After all, everyone already knows what a map is.  At this point, everyone probably even already knows about the most salient maps in the brain, the sensory and motor homunculi.  These are indeed fascinating maps, and the first part of the book explores many of their interesting functions and dysfunctions (like perhaps surprisingly in anorexia).  Unfortunately, after the first couple of chapters that deal with genuine cortical maps, the authors then begin to serially abuse the concept.  The basic goal is to use the intuitive notion of maps to hold together an only loosely related collection of anecdotes about the latest in brain science.  So we get "maps" for higher order motor programs, and emotions, and all sorts of things with no obvious metric and no discussion of how this metric would be preserved in the cortex.  This all culminates in a discussion of the infamous mirror neurons, "the most hyped concept in neuroscience", in which each of these neurons is presented as in itself a "map" of various observed movements.  In other words, they push the word map to the point of meaninglessness, and then beyond.  Without a metric you simply can't talk about a "map".  At best you are describing a "circuit".  At worst you are saying things like, "this is the neuron for recognizing that a lefthanded jewish lesbian from Latin America is scratching the right side of their face with their toe".  

So while there are plenty of nice anecdotes about scientists and their research (and the research subjects and the serendipitous whatever that inspired the research and its feel good implications and blah blah blah) ultimately the book is just too light to get much out of either scientifically or philosophically.  However, the overarching point they make is a good one -- many of our "higher" cognitive functions are clearly related to our brain's relationship to our own body.