Is Your Decaying White Matter Making You Afraid of the Unfamiliar?

If you write about the inner workings of the brain, you soon find out that we don't actually know all that much about how it works. Sure, we have a reasonably good theory of how the brain processes sensory information, and we think we're starting to understand which parts of the brain do what, but how the elements of the brain interact and how all those processes lead up to consciousness is still largely the province of informed speculation.

So it is good to be humble when we theorize about the brain. Especially since we're still finding out things about its function that surprise us. For example, a recent study found out that the white matter of the brain, long treated as the unimportant part, seems to be the basis for the brain's overall "processing speed" (I use the quotes because we should also be careful with the mind-as-computer metaphors) and attention span. Thus, say the researchers, the increasing degeneration of the white matter in the aging brain can lead to, among other things, trouble coping with unfamiliar situations.

The prevailing theory of why people become, in common terms, stuck in their ways in old age is that we develop hard-to-change habits of mind. I've read a number of articles that imply that repeated behavior strengthens neurological pathways that lead to habitual processes, sometimes called "chunking". In other words, the brain forms habits to aid cognition, and sometimes we create bad habits through the same process of repeated behavior. And while this study doesn't undermine that theory, it does offer a complement to it: degeneration of white matter might make it harder to form new habits and leave us more reliant on the old.

Think, for a moment, of what that implies: your mind may inhibit you from comfortably doing something different from what you've done before as you get older. That's somewhat different, and more negative, than the idea that habits are hard to break. It also has implications for marketing: when targeting an older audience, the disruptive techniques that work so well to get the attention of the young might actually be upsetting or disorienting. Not a fun notion for those of us advertising to the baby boomer audience.

The good news, at the individual level, is that scientists believe that cognitive training may help resist white matter decay. But this study provides sobering evidence to support the notion that aging societies (and most societies globally are aging) will be more resistant to what's new and more uncomfortable with change. Which doesn't bode well for those of us who believe some pretty profound changes are necessary.