Opinion – Suzana Herculano-Houzel: Where is the difference between conservative and liberal brains

I love it when neuroscience disappoints people who want easy answers. Biology or environment? Both. Can you learn languages ​​while sleeping, sleeping with headphones on? No, sorry, you have to act to make sense of what you hear. Memory implant, à la Matrix? Sorry, no, memories are circuits carved out of the brain by use, so no use, nothing done. Do we have a part of the brain that takes care of the imagination? No, imagining is reactivating patterns in the brain in the absence of the senses, so the greater your range of experiences, the more elements you will have at your disposal for your imagination.

There are no easy answers when the question is why we are like this or that. Yes, one’s biology is an important starting point, like the floor plan of a house that defines where there are doors and windows. But what goes on between the walls is not in the house, but in the use made of it. “We are what we repeatedly do,” my father would say, paraphrasing Aristotle.

I am glad, therefore, to come across a study of the brains of American conservatives and liberals and their patterns of activity when confronted with controversial immigration videos.

In times of fierce partisanship, where elected officials hang their brains on the entrance hanger and vote only according to their caption, the technological ease of putting volunteers inside an MRI machine and tracking their brain activity, while liberals and conservatives watch to speeches and advertisements with which they agree or disagree, is an invitation to the comparative study of human party nature.

So proceeded four researchers from different strands — a neuroscientist, a sociologist, two psychologists — in the hope of finding differences in the regions of the brain that process motivation or sense signals according to the customer’s partisan inclination.

But the result is much more interesting than researchers expected. There is a detectable difference between the brains of liberals and conservatives, as might be expected, since behavior is the brain’s doing—but the difference is not in a larger or more active brain area in some than the other.

A mathematical technique that allows us to estimate the degree of similarity between variations in activity in the brain of each volunteer who watched provocative videos, like someone comparing music, showed that conservatives are similar to each other, just as liberals are similar to each other, while a group is similar to each other. different from the other, in the pattern of activity of the same part of the brain: the dorsolateral prefrontal cortex, which creates narratives and gives preference to this over that.

Conservatives and liberals listen to the same notes, but they hear completely different music in their brains.