Thursday, October 21, 2010

Phrenology and Neurospeak

Last weekend I attended ACU's Digital Academy, a gathering to help ACU faculty learn some things about communication in a digital age. This weekend's focus was on digital photography and took place in beautiful Gruene, TX.

In between lectures and assignments I wandered into an antique store and found a phrenology head. I brought the head back and showed the group, excited about this purchase for my office. As I was showing off my find we were moving into a session where we'd be working on portraiture, so our teacher, ACU professor Nil Santana, sat me down in Gruene Hall (the oldest band hall in Texas) to take a picture of me with my phrenology head:


If you don't know anything about phrenology, it was a movement that peaked in popularity in the 1800s. The main idea behind phrenology was that your personality could be ascertained by an examination of your skull structure. Slight bulges here or there, or your general skull shape, was believed to correlate with specific psychological traits. That is, there was a close location-by-trait mapping on the skull. This bump correlated with that trait. This tight association between location and trait is vividly captured by the phrenological charts and heads, like the one I purchased. Each location on the skull has the trait listed for that particular area. A bump in his location and you're creative. A bump in this other location and you're sanguine. And so on.

Of course, listening to all this, phrenology seems antiquated and silly. Living in an age of neuroscience and brain scanning we know the truth. Function/location mappings, we know, aren't found on the outer skull; they are found within the structures of the brain.

But before we get too cocky, there are ways in which we still reason about the brain that aren't much more sophisticated than what we see with the phrenologists. For example, a few weeks ago I was talking with a colleague about "brain based" learning in education. One of my observations was that a lot of this "brain based" rhetoric is overblown. All learning, I pointed out, is brain based. It's wonderful that we can now see learning affecting the brain, but let's be clear: All learning, then and now, is brain based.

The reason this observation seems to escape us is that we tend to work with a latent Cartesian dualism when we think about the mind. We think learning, given that it occurs in the mind/soul, isn't really leaving a physical trace. Thus, it seems like a real revelation when we discover that learning affects the brain.

In short, the reason neurospeak (e.g., when we dress learning up in neuroscientific garb) is so powerful is that it is taking place against the backdrop of a Cartesian assumption (i.e., the soul is independent of the brain). Pointing out that learning occurs in the brain seems like a revelation, a real scientific breakthrough, a discovery. But it is only a discovery if we were assuming that the learning was occurring somewhere other than in the brain. Here is Steven Pinker, in his book The Blank Slate, on this point:
The fact that the brain changes when we learn is not, as some have claimed, a radical discovery with profound implications for nature and nurture or human potential...If thought and action are products of the physical activity of the brain, and if thought and action can be affected by experience, then experience has to leave a trace in the physical structure of the brain.

So there is no scientific question as to whether experience, learning, and practice affect the brain; they surely do if we are even vaguely on the right track. It is not surprising that people who can play the violin have different brains from those who cannot, or that masters of sign language or of Braille have different brains from people who speak and read. Your brain changes when you are introduced to a new person, when you hear a bit of gossip, when you watch the Oscars, when you polish your golf stroke--in short, whenever an experience leaves a trace in the mind...We already knew trained violinists play better than beginners or we would never have put their heads in the scanner to begin with. Neural plasticity is just another name for learning and development, described at a different level of analysis.

All this should be obvious, but nowadays any banality about learning can be dressed up in neurospeak and treated like a great revelation of science. According to the New York Times headline, "Talk therapy, a psychiatrist maintains can alter the structure of the patient's brain." I should hope so, or else the psychiatrist would be defrauding her clients. "Environmental manipulation can change the way [a child's] brain develops," the pediatric neurologist Harry Chugani told the Boston Globe. "A child surrounded by aggression, violence, or inadequate stimulation will reflect these connections in the brain and behavior." Well, yes; if the environment affects the child at all, it would do so by changing connections in the brain. A special issue of the journal Educational Technology and Society was intended "to examine the position that learning takes place in the brain of the learner, and that pedagogies and technologies should be designed and evaluated on the basis of the effect they have on student brains." The guest editor (a biologist) did not say whether the alternative was that learning takes place in an immaterial soul. Even professors of neuroscience sometimes proclaim "discoveries" that would be news only to believers in a ghost in the machine: "Scientists have found that the brain is capable of altering its connections...You have the ability to change the synaptic connections within the brain." Good thing, because otherwise we would be permanent amnesiacs.
Phrenology might be silly, but it seems that we still get a lot wrong when it comes to thinking about the mind and the brain.

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