Sunday, January 4, 2009

Lessons from the Video Game Brain

See also Lessons from the Placebo Gene. Also, if you like this kind of thing, see my other fMRI-curmudgeonry(1, 2)

The life of a neurocurmudgeon is a hard one, but once in a while, fate smiles upon us. This article in the Daily Telegraph neatly embodies several of the mistakes that people make about the brain, all in one bite-size portion.

The article is about a recent fMRI study published in the Journal of Psychiatric Research. 22 healthy Stanford student volunteers (half of them male) played a "video game" while being scanned. The game wasn't an actual game like Left 4 Dead(*), but rather a kind of very primitive cross between Pong and Risk, designed specifically for the purposes of the experiment:
Balls appeared on one-half of the screen from the side at 40 pixel/s, and 10 balls were constantly on the screen at any given time. One’s own space was defined as the space behind the wall and opposite side to where the balls appeared. The ball disappeared whenever clicked by the subject. Anytime a ball hit the wall before it could be clicked, the ball was removed and the wall moved at 20 pixel/s, making the space narrower. Anytime all the balls were at least 100 pixels apart from the wall ... the wall moved such that the space became wider.
Essentially they had to click on balls to stop them moving a line. This may not sound like much fun, but the author's justification for using this task was that it allowed them to have a control condition in which the instructions and were the same (click on the balls) but there was no "success" or "failure" because the line defining the "territory" was always fixed. That's actually a pretty good idea. The students did the task 40 times during the scan for 24s at a time, alternating between the two conditions, "no success" (line fixed) and "game with success/failure" (line moves).

The results: While men & women were equally good at clicking balls, men were more successful at gaining "territory" than the women. In both genders, doing the task vs. just resting in the scanner activated various visual and motor-related areas - no surprise. Playing the game vs. doing the control task in which there was no success or failure produced more activation in a handful of areas but only "at a more liberal threshold" i.e. this activation was not statistically reliable. A region-of-interest analysis found activation in the left nucleus accumbens and right orbitofrontal cortex, which are "reward-related" areas. In males, the game-specific activation was greater than in females in the right nucleus accumbens, the orbitofrontal cortex, and the right amygdala.

These areas are indeed "neural circuitries involved in reward and addiction" as the authors put it, but they're also activated whenever you experience anything pleasant or enjoyable, such as drinking water when you're thirsty. Water is not known to be addictive. So whether this study is relevant to video-game "addiction" is anyone's guess. As far as I can tell, all it shows is that men are more interested in simple, repetitive, abstract video games. But that's hardly news: in 2007 there was an International Pac-Man Championship with 30,000 entrants; the top 10 competitors were all male. (If anything in that last sentence surprises you, you haven't spent enough time on the internet.)

Anyway, that's the study. This is what the Telegraph made of it:
Playing on computer consoles activates parts of the male brain which are linked to rewarding feelings and addiction, scans have shown. The more opponents they vanquish and points they score, the more stimulated this region becomes. In contrast, these parts of women's brains are much less likely to be triggered by sessions on the Sony PlayStation, Nintendo Wii or Xbox.
Well, not quite. No opponents were vanquished and no Wii's were played. But so far this is just another fMRI study that attracted the attention of a journalist who knew how to spin a good story. Readers of Neuroskeptic will know this is not uncommon. However, it doesn't end there. Here's the really instructive bit:
Professor Allan Reiss of the Centre for Interdisciplinary Brain Sciences Research at Stanford University, California, who led the research, said that women understood computer games just as well as men but did not have the same neurological drive to win.
"These gender differences may help explain why males are more attracted to, and more likely to become 'hooked' on video games than females," he said.
"I think it's fair to say that males tend to be more intrinsically territorial. It doesn't take a genius to figure out who historically are the conquerors and tyrants of our species – they're the males.
"Most of the computer games that are really popular with males are territory and aggression-type games."
Now this is a theory - men like video games because we're intrinsically drawn to competition, conquest and territory-grabbing. This may or may not be true; personally, in the light of what I know of history and anthropology, I suspect it is, but even if you disagree, you can see that this is an important theory: it makes a big difference whether it's true or not.

However, the fMRI results have nothing to do with this theory. They neither support nor refute it, and nor could they; this experiment is essentially irrelevant to the theory in question. Prof. Allan Reiss is simply stating his personal opinions about human nature - however intelligent & informed these opinions may be. (Just to be clear, it's quite possible that Reiss didn't expect to be quoted in the way he was; he may have, not unreasonably, thought that he was just giving his informal opinion.) The Telegraph's sub-headline?
Men's passion for computer games stems from a deep-rooted urge to conquer, according to research
There are some lessons here.

1. If you want to know about something, study it.

If you want to learn about human behaviour, study human behaviour. Stanley Milgram discovered important things about behaviour; if he had never even heard about the brain, it wouldn't have stopped him from doing that.

Neuroscience can tell us about how behaviour happens. We get thirsty when we haven't drunk water for a while. Neuroscience, and only neuroscience, will tell you how. Some people get depressed or manic. One day, I hope, neuroscience will tell us the complete story of how - maybe mania will turn out to be caused by hyper-stimulation of a certain dopamine receptor - and we'll be able to stop it happening with some pill with a 100% success rate.

However, neuroscience can't tell you what human behaviour is: it cannot describe behaviour, it can only explain it. People know about thirst and depression and mania long before they knew anything about the brain. More importantly, and more subtly, neuroscience can only explain behaviour in the "how" sense; only rarely can it tell you why behaviour is the way that it is.

If someone is behaving in a certain way because of brain damage or disease, that's one of these rare cases. In that case "damage to area X caused by disease Y" is "why". But in most cases, it's not. To say that men like video games because their reward systems are more sensitive to video games is not a "why" explanation. It's a "how" explanation, and it leaves completely open the question of why the male brain is more sensitive to video games. The answer might be "innate biological differences due to evolution", or it might be "sexist upbringing", or "paternalistic culture", or anything else.

(This is often overlooked in discussions about psychiatry. Some people object to the idea that clinical depression is a neuro-chemical state, pointing out that depression can be caused by stress, rejection and other events in life. This is confused; there is no reason why stress or rejection could not cause a state of low serotonin. By extension, saying that someone has "low serotonin" always leaves open the question of why.)

2. Brains are people too

This leads on to a more subtle point. Some people understand the difference between how and why explanations, but feel that if the "how" is something to do with the brain, the "why" must be to do with the brain too. They look at brain scans showing that people behave in a certain way because their brain is a certain way (e.g. men like games because their reward system is more activated by games), and they think that there must be a "biological" explanation for why this is.

There might be, but there might not be. Brains are alive; they see and hear; they think; they talk; they feel. Your brain does everything you do, because you are "your" brain. The astonishing thing about brains is that they are both material, biological objects, and concious, living people, at the same time.

Your brain is not your liver, which is only affected by chemical and biological influences, like hormones, toxins, and bacteria. Your liver doesn't care whether you're a Christian or a Muslim, it cares about whether you drink alcohol. Your brain does care about your religion because some pattern of connections in your brain gives you the religion that you have.

Brain scans, by confronting us with the biological, material nature of the brain, make us look for biological, material why explanations. We forget that the brain might be the way it is because of cultural or historical or psychological or sociological or economic factors, because we forget that brains are people. We tend to think of people as being something beyond and above their brains. Ironically, it's this primitive dualism that leads to the most crude materialistic explanations for human behaviour.

3. Beware neuro-fetishists

There's a doctoral thesis in "Science Studies" to be written about how it came to happen, but that we fetishize the brain is obvious. For much of the 20th century, psychology was seen in the same way. Freud joined Nietschze, Marx and Heidegger in the ranks of Germanic names that literary theorists and lefty intellectuals loved to drop.

Then the bottom fell out of psychoanalysis, Prozac and fMRI arrived and the Decade of the Brain was upon us. Today, neuroscience is the new psychology - or perhaps psychology is becoming a branch of neuroscience. (If I asked you to depict psychology visually, you'd probably draw a brain - if you do a Google image search for "psychology", 10 out of the 21 front page hits depict either a brain or a head; this might not surprise you but it would have seemed odd 50 years ago.) There's a presumption that neuroscience is key to answering both how and why questions about the mind.

Neuroscience is now hot, but what people are mostly interested in are psychological and philosophical questions. People care about The Big Questions like -

"Is there life after death? Do we have free will? Is human nature fixed? Are men smarter/more aggressive/more promiscuous/better drivers than women? Why do people become criminals/geniuses/mad?"

These are good questions - but neuroscience has little to say about them, because they're not questions about the brain. They're questions for philosophers, or geneticists, or psychologists. No brain scan is going to tell you whether men are better drivers than women. It might tell you something about the processes by which make decisions while driving, but only a neuroscientist is likely to find that interesting.

P.S It turns out that people were saying similar things about this research back in Feburary. A blogger who writes about research on video games (neat) wrote about it way back then. So why did the Telegraph decide to resurrect the story as if it were new? That's just another one of life's mysteries.

[BPSDB]

(*) Which is so awesome.

ResearchBlogging.orgF HOEFT, C WATSON, S KESLER, K BETTINGER, A REISS (2008). Gender differences in the mesocorticolimbic system during computer game-play Journal of Psychiatric Research, 42 (4), 253-258 DOI: 10.1016/j.jpsychires.2007.11.010

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