Not for the faint of art. |
Today we're thinking about thinking. Or we could think about thinking about thinking, in indefinite regression, which I do when I'm feeling particularly lazy. That Is Not How Your Brain Works Forget these scientific myths to better understand your brain and yourself. Another scientific overview, this one purporting to dispel certain outdated information. It's dated March 3 of this year, so maybe some of its information is itself out of date. The 21st century is a time of great scientific discovery. And not all the discoveries are fun ones. Cars are driving themselves. That's technology, not science. Vaccines against deadly new viruses are created in less than a year. And half the people refuse to take them, some because they were created in less than a year. (They weren't, actually; mRNA vaccines in particular built on prior years of research.) The latest Mars Rover is hunting for signs of alien life. Even the words "the latest Mars Rover" are pretty cool when put like that. But we’re also surrounded with scientific myths: outdated beliefs that make their way regularly into news stories. And sometimes, outright misinformation. As a neuroscientist, I see scientific myths about the brain repeated regularly in the media and corners of academic research. Three of them, in particular, stand out for correction. I guarantee you there are more than three of them, but I suppose every article has its word limit. After all, each of us has a brain... With the possible exception of anti-vax cretins. ...so it’s critical to understand how that three-pound blob between your ears works. Or, in the case of anti-vaxxers, doesn't. Myth number one is that specific parts of the human brain have specific psychological jobs. I'm just going to highlight from here on out; the article obviously goes into more depth. This view of the brain became popular in the 19th century, when it was called phrenology. Its practitioners believed they could discern your personality by measuring bumps on your skull. "Hm. This person is a klutz, and this other person likes to be in bar fights." Most neurons have multiple jobs, not a single psychological purpose. Main job, secondary job, side hustle. The economy sucks. Perhaps the most famous example of puzzle-piece thinking is the “triune brain”: the idea that the human brain evolved in three layers. The deepest layer, known as the lizard brain and allegedly inherited from reptile ancestors, is said to house our instincts. The middle layer, called the limbic system, allegedly contains emotions inherited from ancient mammals. And the topmost layer, called the neocortex, is said to be uniquely human—like icing on an already baked cake—and supposedly lets us regulate our brutish emotions and instincts. "Supposedly." And if a uniquely human and rational neocortex controls those beasts, then we have the most highly evolved brain in the animal kingdom. Yay for humans, right? But it’s all a myth. In reality, each species has brains that are uniquely and effectively adapted to their environments, and no animal brain is “more evolved” than any other. Which is what I've been saying with my highly-evolved brain. Myth number two is that your brain reacts to events in the world. Well, first we have to know about said events, and sometimes those are filtered through questionable sources, so... oh, wait, she's talking about something else. All your neurons are firing at various rates all the time. What are they doing? Busily making predictions. No matter how hard we wish it were true, we are not living in the present. The third myth is that there’s a clear dividing line between diseases of the body, such as cardiovascular disease, and diseases of the mind, such as depression. Yeah, I've known this for a while. One semester of biological psychology doesn't make me an expert on neurology, but it is enough to understand that mental illness is often a form of physical illness. The idea that body and mind are separate was popularized by the philosopher René Descartes in the 17th century (known as Cartesian dualism) and it’s still around today, including in the practice of medicine. (Hence today's title.) Every mental experience has physical causes, and physical changes in your body often have mental consequences, thanks to your predicting brain. One interesting recent line of research, which I don't think the article mentions, is how intestinal microorganisms can affect one's mental health. And it's trivially true that injuries to the brain can cause mental illness. The brain is, after all, a physical organ, and it can get off-track just like any other organ. Under the hood, however, your brain creates your mind while it regulates the systems of your body. That means the regulation of your body is itself part of your mind. Mind (and liver and spleen and gonads) blown. We adapt to what we learn. But sometimes hypotheses are so strong that they resist change. They are maintained not by evidence but by ideology. They become scientific myths. That's the real takeaway here, at least in my opinion: our body of knowledge changes, and we need to adapt to it. It can be wrong, but it's still the best means we have of understanding the world outside... and the one within. When you hear some scientist say "A is true," and then a couple of months later say, "A is not true; B is true," they're not being wishy-washy or flippy-floppy; they're adapting to new data. It would be good if more people could do that. |