19 September 2012

Skullduggery

A few of the appreciative commenters on my New Statesman essay about neuroscientism have concluded that popularized neuroscience is “the new phrenology” or “phrenology 2.0″. It didn’t make it into the final draft of my essay, but I had actually put this point to my interviewee, the neuroscientist Paul Fletcher, and his answer was rather interesting:

[P]eople are frequently a bit simplistic in using this criticism — after all phrenology, in considering the mind as consisting of dissociable cognitive faculties, was not altogether misguided. The main problem with phrenology (aside from the assumption that development of particular cognitive faculties must be associated with increased regional brain volume and hence bigger skull bumps) was that it was seemingly arbitrary in how it divided up the components of the mind. Nowadays, cognitive scientists pride themselves on having a more realistic view of how we may separate and categorise mental processes, but all (I hope) would admit that we are still building up our vague pictures of how mental faculties are structured. So when someone confidently assigns a particular process to a particular brain region, they are on the same very thin ice which Franz Gall (the original phrenologist) skated.

Even so, some trace of phrenology survives in our current best theories, uncertain as they still are:

I think that a healthy view of the brain based on current knowledge is that there is undoubtedly specialisation of brain regions — a slightly phrenological (phrenologous?) view — but that this co-exists with a pattern of remarkable connectivity, meaning that any given function is likely to be carried out across circuits that themselves are plastic (for example, altering their connection strength through changes in synapses) in response to experience.

So let’s not be too hard on phrenology while taking out the neurotrash.