The Idiot Brain: A Neuroscientist Explains What Your Head is Really Up To

by Dean Burnett

Walking two miles a day has been reported as being good for the brain, but then it’s probably good for every part of the body.1

There are nerve clusters in our spines that help control our locomotion without any conscious involvement.

One of the brain’s more prominent skills is the ability to ignore anything that becomes too predictable, no matter how important it may be (this is why soldiers can still get some sleep in war zones).

If blindfolded while wearing nose plugs, your typical person can often mistake potato for apple.

To clarify; we still don’t know the purpose of sleep! It’s been observed (if you adopt a fairly loose definition) in almost every other type of animal, even the simplest kinds like nematodes, a basic and common parasitic flatworm.

Aquatic mammals have evolved methods of sleeping with only half the brain at a time because if they slept fully they’d stop swimming, sink and drown.

sleep reduces the signal strength of weak neurological connections to make them easier to remove.12 Another is sleep facilitates reduction of negative emotions.

short-term memories last about a minute max., whereas long-term memories can and do stay with you your whole life. Anyone referring to something they recall from a day or even a few hours ago as ‘short-term memory’ is incorrect; that’s long-term memory.

hippocampus is the place that the actual encoding happens. People with a damaged hippocampus can’t seem to encode new memories; those who have constantly to learn and remember new information have surprisingly large hippocampi (like taxi drivers having enlarged hippocampal regions that process spatial memory and navigation, as we’ll see later), suggesting greater dependence and activity.

Remembering that the capital of France is Paris is a semantic memory, remembering the time you were sick off the Eiffel Tower is an episodic memory.

Short-term memory is largely aural, focusing on processing information in the form of words and specific sounds. This is why you have an internal monologue, and think using sentences and language, rather than a series of images like a film.

Alcohol is a depressant.13 Not because it makes you feel dreadful and depressed the next morning (although, good lord, it does), but because it actually depresses activity in the nerves of the brain; it reduces their activity like someone lowering the volume on a stereo.

Aplysia neurons can have axons (the long ‘trunk’ part of a neuron) up to a millimetre in diameter.

Overall, the more the brain retains control over events, the less scary they are.

Knowledge is knowing that a tomato is a fruit; wisdom is not putting it in a fruit salad.’

Empty vessels make the most noise

The phenomenon of less-intelligent people being more confident has an actual scientific name: the Dunning–Kruger effect.

a criminal who held up banks after covering his face with lemon juice, because lemon juice can be used as invisible ink, so he thought his face wouldn’t show up on camera.5

intelligent brains apparently use less power.

Intelligence isn’t the work of one dedicated brain region but several, all interlinked. In intelligent people, it seems these links and connections are more efficient and organised, requiring less activity overall.

Tall people are smarter than shorter people. It’s true. This is a fact that many find surprising, even offensive (if they’re short).

Intelligence itself is heritable to a surprisingly high degree;

Another interesting/weird thing about intelligence? It’s increasing worldwide, and we don’t know why. This is called the Flynn effect, and it describes the fact that general scores of intelligence, both fluid and crystallised, are increasing in a wide variety of populations around the world with every generation, in many countries, and despite the varying circumstances that are found in each one.

humans can actually smell in the region of 1 trillion odours.

A 2007 paper by Malika Auvray and Charles Spence5 revealed that if something has a powerful smell while we’re eating it the brain tends to interpret that as a taste, rather than an odour, even if it’s the nose relaying the signals.

Lining this tube is the organ of Corti. It’s more of a layer than a separate self-contained structure, and the organ itself is covered with hair cells, which aren’t actually hairs, but receptors, because sometimes scientists don’t think things are confusing enough on their own.

These hair cells detect the vibrations in the cochlea, and fire off signals in response. But the hair cells only in certain parts of the cochlea are activated due to the specific frequencies travelling only certain distances. This means that there is essentially a frequency ‘map’ of the cochlea, with the regions at the very start of the cochlea being stimulated by higher-frequency soundwaves (meaning high-pitched noises, like an excited toddler inhaling helium) whereas the very ‘end’ of the cochlea is activated by the lowest-frequency soundwaves (very deep noises, like a whale singing Barry White songs). The areas between these extremes of the cochlea respond to the rest of the spectrum of sounds audible to humans (between 20 Hz and 20,000 Hz).

What do toast, tacos, pizza, ice-cream, jars of spread, bananas, pretzels, crisps and nachos have in common? The image of Jesus has been found in all of them

In the 1950s, Friedman and Rosenhan came up with Type-A and Type-B personalities,6 with Type-As being competitive, achievement-seeking, impatient and aggressive, and Type-Bs not being these things.

If you are angry and don’t want to show it, the brain’s versatility means there are ways to be aggressive without using crude violence. You can be ‘passive aggressive’, where you make another person’s life miserable via behaviour they can’t really object to.

people raised in a Western capitalist society, constantly told they can have anything they want, will feel more in control of their own lives, whereas someone living in a totalitarian regime probably won’t.

This all gave rise to what is now known as the Zeigarnik effect, where the brain really doesn’t like things being incomplete.

Philosophers as far back as Plato suggested that laughter is an expression of superiority. When someone falls over, or does or says something stupid, this pleases us because they have lowered their status compared with ours.

It’s a lot easier to laugh when part of a group, which is why stand-up comedy is rarely a one-to-one practice.

laughter. Research by Sophie Scott has revealed people to be extremely accurate when it comes to identifying someone laughing genuinely and someone pretending, even if they sound very similar.

A 2013 Oxford University study claimed to have demonstrated it via sophisticated computer models that showed social relationships do in fact require more processing (and therefore brain) power.28 Interesting, but not conclusive; how do you model friendship on a computer? Humans have a strong tendency to form groups and relationships, and concern for others. Even now, a complete lack of concern or compassion is considered abnormal (psychopathy).

Only in 1973 did the American Psychiatric Association declassify homosexuality as a mental disorder.

(nearly 1 in 4 people experience some manifestation of mental disorder, according to the data2) and it’s easy to see why mental health problems are such a controversial issue.

Methadone is supplied in a form than can only be swallowed (it looks like worryingly green cough syrup), whereas heroin is usually injected. But so strong a connection does the brain make between injection and the effects of heroin, that the act of injecting causes a high. Addicts have been known to pretend to swallow methadone, then spit it into a syringe and inject it.