This article from The New York Times, Mental Reserves Keep Brains Agile, illustrates a central point that Greg Downey and I want to make with neuroanthropology. First, what you do with your brain, how that doing plays out in an environment, and how that playing out feeds back into the workings of your brain are a central part of what makes us human—and thus is a central part of how anthropology should approach the study of ourselves.
What You Do: Having an active brain over your life course means that less neurons are likely to be lost and more connections actively generated and maintained. The brain, like your muscles, is use-it-or-lose-it—we have the most neurons that we’ll ever have when we are children, and as children, we go through a lot of “selective pruning”. That said, research has also shown the we keep producing new neurons throughout our lives, overturning a long-standing idea that we only get one set of neurons for life.
Doing in Environment: As the article notes, “there is no ‘quick fix’ for the aging brain, and little evidence that any one supplement or program or piece of equipment can protect or enhance brain function — advertisements for products like ginkgo biloba to the contrary.” Despite our wishes to the contrary, we need to do plenty of stuff in a challenging environment to maintain our cognitive reserves.
Playing Back into the Brain: Both social relationships and physical activity make a difference to your brain. Greg likes the physical side, so I will just highlight one quote here: “Long-term studies in other countries, including Sweden and China, have also found that continued social interactions helped protect against dementia. The more extensive an older person’s social network, the better the brain is likely to work, the research suggests.”
That said, we can also draw two other lessons from the article. First, as I pointed out briefly in my Introduction, we should avoid over-localizing function and pathology in any one area. Brains are not as hard-wired as computers; people’s physiology is variable (including their brains). We are soft wired, or “wet wired” to draw on the metaphor of a 1995 book. As the article states, “up to two-thirds of people with autopsy findings of Alzheimer’s disease were cognitively intact when they died.” The second point, and a crucial one for neuroanthropology, is the implicit framing of the article. The title reads “Mental Reserves Keep Brains Agile,” re-using a very old mind/body metaphor. While Jane Brody speaks of social and physical activity, the main causal concepts are cognitive and physical: the cognitive reserve, the number of neurons present. Subsequently, Brody has our social, physical and symbolic worlds revolve around the mind/body dichotomy. Neuroanthropology needs to develop the research, the language, and the popular models to show what this article actually tells us: people’s social lives, from walking in malls to playing bridge, make a difference in the blood flow and neuronal connections of the brain. Our lives play back into our brains.