3 POPULAR NEUROSCIENCE IDEAS…THAT AREN’T REALLY TRUE
Like science? Sure – we all do. And you like to stay informed about it – but it’s not like you’re going to set aside hours of your time for studying scholarly journals, when you could be…eating ham, or whatever it is you enjoy doing.
And who could blame you? Science journals don’t have that succulent honey-glazed flavor. But unfortunately for you (you poor, poor fool), articles that summarize new discoveries into quick soundbytes are often written by people who have no more formal training in neuroscience than you do.
Now, a lot of the time, this isn’t much of a problem, because many of these writers still do their best to conduct detailed interviews and keep their facts straight. Except that when one of them oversimplifies an idea or misconstrues it a little, others will tend to repeat it, and some of them will misconstrue it a little more, until what started as an innocent game of “telephone” somehow produces a sentence even more embarrassingly racist than “telephone’s” original name. Okay, that metaphor got away from me.
What I’m trying to say is, here are three neuroscience ideas that tend to get repeated a lot in the press – even though they aren’t quite true to the facts.
1. Dopamine is a “reward chemical.”
File this one under “oversimplification.” In some areas of the brain – the nucleus accumbens, for example – dopamine does help trigger neural activity patterns that are involved in feelings of reward. But in many of the same areas, dopamine helps “cap off” that same rewarding feeling before it gets too strong – while in other parts of the body, it has completely different functions, like suppressing incoming sensory signals and regulating muscle tone. Meanwhile, an excess of dopamine in the brain has been linked to schizophrenic hallucinations. So as far as dopamine’s overall role, the best-defined theory right now is that dopamine helps modulate the salience of some signals at the expense of others – in other words, it helps our brains recognize what’s important – and that plays out in all kinds of ways all over the brain.
File this one under “oversimplification.” In some areas of the brain – the nucleus accumbens, for example – dopamine does help trigger neural activity patterns that are involved in feelings of reward. But in many of the same areas, dopamine helps “cap off” that same rewarding feeling before it gets too strong – while in other parts of the body, it has completely different functions, like suppressing incoming sensory signals and regulating muscle tone. Meanwhile, an excess of dopamine in the brain has been linked to schizophrenic hallucinations. So as far as dopamine’s overall role, the best-defined theory right now is that dopamine helps modulate the salience of some signals at the expense of others – in other words, it helps our brains recognize what’s important – and that plays out in all kinds of ways all over the brain.
Still, it's hard to deny the sexiness of an oxytocin tattoo.
2. Oxytocin is a “love hormone.”
As I’ve talked about here, oxytocin does all kinds of things in the brain and throughout the body. It’s released during orgasm and childbirth in women, but it tends to be highest pre-orgasmically in men. What exactly this means, no one’s sure – in part because other chemicals, such as dopamine and norepinephrine, are also elevated during sex and cuddling; and those chemicals are also associated with feelings of reward and pleasure. Oxytocin also appears when animals feel full after eating, and it seems to be involved in timing acts of childbirth. Oh, and for some reason it makes people racist. The short of it is that oxytocin tends to pop up whenever “family-related” things are going on, but there’s no consensus yet on whether it actually inspires those behaviors, or if it’s triggering other changes in response to them.
As I’ve talked about here, oxytocin does all kinds of things in the brain and throughout the body. It’s released during orgasm and childbirth in women, but it tends to be highest pre-orgasmically in men. What exactly this means, no one’s sure – in part because other chemicals, such as dopamine and norepinephrine, are also elevated during sex and cuddling; and those chemicals are also associated with feelings of reward and pleasure. Oxytocin also appears when animals feel full after eating, and it seems to be involved in timing acts of childbirth. Oh, and for some reason it makes people racist. The short of it is that oxytocin tends to pop up whenever “family-related” things are going on, but there’s no consensus yet on whether it actually inspires those behaviors, or if it’s triggering other changes in response to them.
3. The brain has a “speech area” or a “face area”
…or an [anything] area, for that matter. Now, it’s true that many brain regions become specialized for tasks like recognizing faces or organizing our sense of touch - but here’s the thing: 1) these regions can’t work alone, and 2) many of them can be taught to perform completely different functions. Every time a scientist claims that such-and-such function can’t happen without such-and-such part of the brain, a new patient comes along and proves them wrong - so modern neuroscientists have gotten very cautious about making such blanket claims. The point is that each person’s brain is highly versatile, and it constantly changes and adapts - as a unified system – to the unique circumstances of that person’s life.
…or an [anything] area, for that matter. Now, it’s true that many brain regions become specialized for tasks like recognizing faces or organizing our sense of touch - but here’s the thing: 1) these regions can’t work alone, and 2) many of them can be taught to perform completely different functions. Every time a scientist claims that such-and-such function can’t happen without such-and-such part of the brain, a new patient comes along and proves them wrong - so modern neuroscientists have gotten very cautious about making such blanket claims. The point is that each person’s brain is highly versatile, and it constantly changes and adapts - as a unified system – to the unique circumstances of that person’s life.
Are you seeing a pattern here? All these misconceptions stem from the same basic tendency: we humans like to classify things – to chop them up and sort them into neat little boxes. While this works well with plenty of things in the world (computer parts, for example, or delicious lunchmeats) it’s not so helpful when we’re talking about a complex system of interwovengradients (like, for example, a family of languages or the chemicals in a brain).
Simplifying and summarizing scientific discoveries can be helpful for communicating them – but it can also lead our thinking down paths that aren’t true to all the known facts. The brain is a lot more complex than you might expect – but that also means it’s a lot more mysterious, and more fun to explore.
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