By Christian Jarrett)
So, there’s a new study out (pdf) that’s used brain scanning to investigate how reading a book changes your brain. It tripped my skeptic’s radar right away because our brains are changing all the time, and pretty much anything we do influences those changes. And we already knew the power of reading novels, didn’t we? You follow a story, meet characters, learn things. Nonetheless the media are all over this neuroscience study, hyping and misinterpreting the results. Among the most daft was “Reading a good book may make permanent changes to your brain” from the UPI news agency. That’s quite a leap given that the study only looked at brain changes up to five days after participants had finished reading a novel. But let’s hold off on debunking the headlines for now and take a look at what the researchers actually did.
They used a technique known as “resting state fMRI”, which involves scanning a person’s brain while they lie in the scanner doing nothing. Nineteen volunteers (12 women) visited a lab at Emory University to have their brains scanned in this way daily for 19 days. The first five visits, the participants just turned up for the scan. The middle nine days they spent each evening before a scan reading a chapter from Pompeii: A Novel by Robert Harris (he must be loving this free publicity!). Each morning before their scan the participants completed a quiz about the book’s content (e.g. “What is Marcus Attilius Primus’s job?”), and answered questions about how the book made them feel. The final five days the volunteers had daily scans again without any quizzes or reading – this was to look for lingering effects from the days spent reading the book.
To understand what the researchers say they found, we need to rewind a little to take a look at their technique of choice: resting-state fMRI. Most brain scanning studies involve getting participants to perform specific tasks in the scanner and then looking to see what patterns of brain activity are correlated with these tasks. Resting-state fMRI is unusual because the participant is told to do nothing (the specific instruction in this new research was to rest quietly with your eyes closed). Previous research on the resting-state has found there are areas of brain activity that fluctuate in tandem, which is suggestive of functional connections between correlated brain regions. These resting connective patterns tend to be fairly consistent over time, and there’s evidence they may be unusual in conditions like dementia and schizophrenia. This new research looked to see how these patterns of resting brain connectivity were altered over the 19 days of the study.
The important result, according to the study authors – Gregory Berns and his colleagues – is that the participants’ averaged brain connectivity patterns at rest were altered by the experience of reading Pompeii. The researchers highlighted three functional hubs in particular that appeared to show changes specifically related to the reading phase of the study. These hubs were in left-frontal regions, implicated in language function and representing other people’s perspectives; and in a region near the central sulcus, likely involved in controlling the body and processing touch. These changes lingered during the five-day period after the participants had finished reading the book.
It’s important to note that the researchers didn’t ask the participants to do any psychological tests after the book reading, so they don’t know the functional significance of these brain changes. Other issues to bear in mind: We don’t know what the participants were doing with their minds while they were in the scanner (more criticism of resting-state scans here); we don’t know what they were getting up to during the 19 days of the study when they weren’t at the lab or reading the book; it’s very hard to tell what influences on resting brain connectivity were due to reading per se and which were due to the quizzes conducted just before the scans. There’s also no information in the paper on the size of the connectivity changes. There’s no control group, so we don’t know if spending time in a bar with friends (or any other activity) each evening prior to the scan would have had a larger or different effect than reading a novel. We also don’t know much about the participants – whether they read regularly or if this was the first novel they’d read in years.
Despite all these unknowns, the researchers speculated that the connectivity changes they observed may have optimized their participants’ brains for reading stories and understanding other people’s perspectives. This is plausible (in fact, behavioural research by others has shown such benefits of reading; although this research has been criticized), but not exactly revelatory – we already know that practice at almost anything brings improvement, and it would be astonishing if this wasn’t accompanied by brain changes. The modifications to the functional hub involved in motor control and touch was arguably more surprising. The researchers speculated that this may reflect the fact that reading triggers brain activity associated with bodily sensations. “This is called the Theory of Embodied Semantics,” they explained – tactile metaphors and stepping into the shoes of fictional characters can activate the brain pathways involved in controlling and representing our own bodies. Again, that’s plausible I suppose. But at risk of getting repetitive, we can’t know the meaning of these connectivity changes without any behavioral tests. Unfortunately, it was this particular finding that led the Digital Journal to run the nonsense headline: “An easy way to lose weight: Read a fast-paced novel.” Amazingly, neither the researchers nor the Digital Journal mentioned mirror neurons. Hooray!
Celebration over. I’ve told you what the research found. Now look at some of the other crazy news headlines it inspired. I’ll quote the headline, then give my brief reaction:
Brain function ‘boosted for days after reading a novel’ (The Independent). “Boosted” implies there was some benefit here, but the study didn’t demonstrate any functional benefits. Also, it’s worth noting that some patterns of connectivity, largely in the cerebellum, were actually reduced by the reading experience. Furthermore, some increases in connectivity started to decline again early in the reading phase of the study. In the Indy news report, lead author Berns says: ““We already knew that good stories can put you in someone else’s shoes in a figurative sense. Now we’re seeing that something may also be happening biologically.” This comment is amusingly similar to Jerry Fodor’s dry observation in his classic 1999 neuroskeptical essay: “… [W]e always sort of knew that there’s a difference between nouns and verbs, or between thinking about teapots and taking a nap, we didn’t really know it till somebody found them at different places in the brain. Now that somebody has, we know it scientifically.”
Books Help Improve Brain Functions for Days (Parent Herald) / For A Better Brain, A Plan To Feed It Stories (Forbes). See my comments above.
Reading a novel exercises ‘muscles’ in the brain, researchers find (LA Times). There are no muscles in the brain.
Why You Should Read More Novels (Fastcodesign.com). There are many good reasons why you should read more novels, this new study doesn’t add to them.
You get the idea! I’m going to finish with a suggestion that the potentially important finding from this study is nothing to do with the brain-boosting effects of novels, but about the use of resting-state brain scans as a diagnostic tool (you can see why that didn’t make the headlines). The use of the scans in this way is predicated on the idea that they’re stable and reliable. Map someone’s resting-state connectivity today and you learn something meaningful about the long-term state of their brain, or so it’s hoped. Supporting this, Berns and his team cite past research on the stability of resting-state networks over a course of a year. Their motive was to show that you’d really expect resting-state connectivity patterns to be stable over 19 days, and it’s therefore a big deal that reading a book changed these networks. But let’s flip this. If an activity as straight-forward as reading a book has a significant effect on resting-state connectivity networks, this presumably undermines the clinical usefulness of resting-state scans. Or were the changes not that meaningful? The researchers can’t have it both ways, can they?
Christian Jarrett is a cognitive neuroscientist turned science writer. He’s editor of The British Psychological Society’s Research Digest blog, staff writer on their magazine The Psychologist, and a columnist for 99U. He’s also author of The Rough Guide to Psychology, editor of 30-Second Psychology, and co-author of This Book Has Issues. His next book due in 2014 is Great Myths of the Brain.
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