Back in the 1960s, Nobel-prize winning research shook our understanding of what it means to be a conscious entity. Epilepsy patients who’d had the thick bundle of nerves connecting their two brain hemispheres either severed or removed (as a drastic treatment for their epilepsy) responded in laboratory tasks as if they had two separate minds.
It’s an unsettling idea that has appeared in psychology textbooks for decades. But dig into the original studies and you’ll find the evidence for split brains leading to split minds was mostly descriptive. Now a team of researchers led by Yair Pinto at the University of Amsterdam has conducted systematic testing of two split-brain patients over several years, specifically to find out whether the division of their brains has also separated their consciousness. In fact, the results, published recently in the journal Brain, suggest their consciousness remains unified. It may be time to rewrite the textbooks.
“One 60-minute run can add 7 hours to your life” claimed The Times last week. The story was based on a new review in Progress in Cardiovascular Diseases that concluded that runners live, on average, three years longer than non-runners and that running will do more for your longevity than any other form of exercise. But there’s more to running than its health-enhancing effects. Research published in recent years has shown that donning your trainers and pounding the hills or pavements changes your brain and mind in some intriguing ways, from increasing connectivity between key functional hubs, to helping you regulate your emotions. The precise effects sometimes vary according to whether you engage in intense sprints or long-distance running. Here, to coincide with a new feature article in The Psychologist – “Minds run free” – we provide a handy digest of the ways that running changes your mind and brain.
If the courts wanted to know if a suspected sex offender was attracted to children, they could ask him or her, or they could ask experts to measure signs of the suspect’s sexual arousal while he or she looked at different images. But a devious suspect would surely lie about their interests, and they could distract themselves to cheat the physical test.
Brain scans offer an alternative strategy: research shows that when we look at images that we find sexually attractive, our brains show distinct patterns of activation. But of course, the same issues of cheating and deliberate distraction could apply.
Unless, that is, you could somehow prevent the suspect from knowing what images they were looking at, by using subliminal stimuli that can’t be seen at a conscious level. Then you could see how their brain responds to different types of image without the suspect even knowing what they were looking at.
This is the essence of a strategy tested in a new paper in Consciousness and Cognition. Martina Wernicke at Asklepios Forensic Psychiatric Hospital of Gottingen and her colleagues have provided a partial proof of principle that it might one day be possible to use subliminally presented images in a brain scanner to provide a fraud-proof test of a person’s sexual interests. It’s a potentially important break-through for crime prevention – given that deviant sexual interest is one of the strongest predictors of future offences – but it also raises important ethical questions.
Travelling in space can play havoc with the human mind. Because of micro-gravity, astronauts frequently experience weird sensory effects, such as the world suddenly appearing upside down. Even their ability to rotate objects in their mind’s eye is sometimes affected. A new open-access study in the journal Microgravity is the first to explore the structural brain changes caused by spaceflight and which may contribute to, or reflect, these and other sensory and cognitive effects.
Vincent Koppelmans and his colleagues, including Jacob Bloomberg at NASA’s Johnson Space Center in Houston, compared brain scans taken of 27 astronauts before a space mission with a second scan taken once they were back on earth. The results revealed a mix of shrinkage and enlargement across the brain. There were widespread reductions in grey matter as well as some more localised increases in grey matter in regions that are involved in sensory processing and motor control.
Adolescents take more risks than adults: they are more likely to binge drink, have casual sex, commit crimes and have serious car accidents. In fact, adolescence is a paradox because it is a time of peak physical fitness, but also the time when people are most likely to be injured or killed in an accident. For this reason, it’s critical to understand what drives teenagers to take more risks. To date, many explanations of teenage risk taking have focused on the positive side of these behaviours: the rewarding “kick” that comes from taking a risk that ends well. Some studies have shown that teenagers experience more of this rewarding feeling, and this contributes to the increased risk taking seen at this age.
Fewer studies have considered how teenagers respond when risks turn out badly. This is important because all our previous experiences, both good and bad, affect our subsequent behaviour. If we make a risky decision like gambling money, and it pays off, it’s more likely we’ll decide to gamble again in the near future. Equally, if we take a gamble and it turns out badly, we’ll probably be a bit more reserved next time. But it turns out that some teenagers don’t respond like this: according to a new study in NeuroImage, some of them do not adjust their behavior so readily when things go wrong, and this may be linked to a distinct pattern of activation in their brains.
Coming up with the perfect recipe for crisps or the ideal marketing strategy for a soft drink used to depend on explicit measures. In focus groups and surveys, consumers were asked which product tasted best or which commercial was most appealing. But these measures are imperfect: consumers may choose to hide their true opinions or they might not be fully aware of their own preferences. Food and drinks companies need more objective measures. Currently their best hope is functional magnetic resonance imaging (fMRI).
The idea is that somewhere in the brain, a “buy button” is hidden away: a region (or combination of regions) that influence your purchase decision. The promise of neuromarketing is that one day, we will be able to find this region, record its activity when you watch an ad or sample a product, and then predict how well this product will sell. So far, the success has been limited. But in a recent study in NeuroImage, Simone Kühn from the University Clinic Hamburg-Eppendorf and her colleagues claim to have found “multiple ‘buy buttons’ in the brain”.
Deep brain stimulation is a medical procedure that involves implanting electrodes permanently into the brain and using them to alter the functioning of specific neural networks. A battery inserted subcutaneously in the chest provides the device with power. One application of the technology is as a treatment for Parkinson’s Disease, a neurodegenerative condition that causes tremors and difficulties moving. While the treatment can bring about an impressive alleviation of symptoms, research suggests that Parkinson’s patients often struggle to adjust psychologically. Now a case study published in the British Journal of Health Psychology has provided some of the first insights into what it’s like for a patient to contemplate undergoing surgery for deep brain stimulation, and then to adjust in the immediate aftermath.
The traffic lights turn amber: should you brake or accelerate on through? If there’s a teenager at the wheel, the chances are he or she will put their foot down and keep going. Teenagers love taking risks, more so than any other age group. This is partly down to the immaturity of the teen brain: they do not yet show the same connectivity between frontal decision making areas and deeper reward-related brain areas, as compared with adults. But there’s also a social element. When an adult is around, teens tend to take fewer risks, and their brains show less reward-related activity after taking a risk, a phenomenon that psychologists call “social scaffolding” because it is as if the adult presence is helping the teen to attain adult-like behaviour. A new study in Developmental Science builds on these findings and makes the claim that a teenager’s brain is influenced to a greater extent by the presence of his or her mother than by an unfamiliar adult. Continue reading “Teenagers’ brains process risk differently when Mum is around”→
If you want to maximise a person’s intellectual potential, the general consensus for a long time has been that you need to start young. According to this traditional view, early childhood offers a precious “window of opportunity” or “sensitive period” for learning that closes slowly as we reach adolescence. It’s the reason that toddlers find it easier to master the accent of a foreign language, for instance.
Sarah-Jayne Blakemore at University College London has spent the last decade over-turning some of these assumptions, showing that the adolescent brain is still remarkably flexible as it undergoes profound anatomical changes. “The idea that the brain is somehow fixed in early childhood, which was an idea that was very strongly believed up until fairly recently, is completely wrong,” she told Edge in 2012. The transformation is particularly marked in the prefrontal lobes (located behind the forehead) and the parietal lobes (underneath and just behind the top of your head): two regions that are involved in abstract thought.
The upshot is that teenagers may go through a second sensitive period, in which they are particularly responsive to certain kinds of intellectual stimulation. A new paper from Blakemore’s lab, published in Psychological Science, builds on this idea, showing that our ability to learn certain kinds of analytical skills doesn’t diminish after childhood, but actually increases through adolescence and into early adulthood.
Poets have long described the mind-altering effects of a passionate relationship – “my love’s a noble madness” wrote John Dryden. “Of all the emotions,” said Cicero, “there is none more violent than love. Love is a madness.” Psychology research is beginning to back this up. A recent study found that students in the early days of a passionate relationship exhibited reduced cognitive control in basic psychological tests. Now brain researchers in Japan have started to look for the neural correlates of these effects. Writing in Frontiers in Psychology, Hiroaki Kawamichi and his colleagues report the results of their brain imaging experiment showing that participants in the relatively early stages of a romantic relationship had reduced grey matter in a region of the brain involved in processing reward, which might suggest their brains had adjusted to the intensity of their love affair.