Some brains struck by pathology seem to stave off its effects thanks to a “cognitive reserve”: a superior use of mental resources that may be related to the way we use our brains over a lifetime, for instance through high levels of education or, possibly, learning a second language.
Bilingual people certainly seem to use their brains differently. For example, practice at switching languages has been associated with enhanced mental control. It’s even been claimed that being bilingual can stave off dementia by up to four or five years.
If true, this would have serious implications for public policy – learning a second language would be as much a desirable health behaviour as it is an educational or cultural one. But are the brain benefits of bilingualism real? The Journal of Alzheimer’s Disease has published a systematic review and meta-analysis to establish the strength of the evidence base.
The hot-headed “macho man”, who acts first and thinks later, has long been popular in movies. Now there’s psychological evidence to support it. A new study in the Psychological Science finds that a short-term rise in testosterone – as might occur when in the presence of an attractive potential mate, or during competition – shifts the way men think, encouraging them to rely on quick, intuitive, and generally less accurate, judgements, rather than engaging in careful, more deliberate thought.
The authors of the new paper, led by Amit Bhattacharjee at Erasmus University, believe this anti-profit bias leads many voters and politicians to endorse anti-profit policies that are likely to lead to the very opposite outcomes for society that they want to achieve. “Erroneous anti-profit beliefs may lead to systematically worse economic policies for society, even as they help people satisfy their social and expressive needs on an individual level” they said.
Thinking like a scientist is really hard, even for scientists. It requires putting aside your own prior beliefs, evaluating the quality and meaning of the evidence before you, and weighing it in the context of earlier findings. But parking your own agenda and staying objective is not the human way.
Consider that even though scientific evidence overwhelming supports the theory of evolution, a third of Americans think the theory is “absolutely false”. Similarly, the overwhelming scientific consensus is that human activity has contributed to climate change, yet around a third of Americans doubt it.
We Brits are just as blinkered. In a recent survey, over 96 per cent of teachers here said they believed pupils learn better when taught via their preferred learning style, even though scientific support for the concept is virtually non-existent. Why is it so hard to think like a scientist? In a new chapter in the Psychology of Learning and Motivation book series, Priti Shah at the University of Michigan and her colleagues have taken a detailed look at the reasons, and here I’ve pulled out five key insights:
After chemotherapy treatment, many patients say their mind has been affected. For example they describe symptoms such as feeling confused, memory problems and difficulty concentrating – a phenomenon that has been dubbed “chemobrain” (Cancer Research UK has more information).
The causes are little understood. Are these apparent neuropsychological effects due to a direct physical effect of chemotherapy on the brain? Or could it be the stress and worry involved in chemotherapy that is responsible? Perhaps it’s both. To find out more, Mi Sook Jung at Chungnam National University in South Korea, and colleagues, conducted repeated brain scans and neuropsych tests with breast cancer patients undergoing chemo and compared them with similar cancer patients not on chemo and healthy controls. Reporting their results in Brain Imaging and Behaviour, the researchers hope a better understanding of the nature of “chemobrain” and its causes will make it possible for health professionals to offer patients better support and care.
In the early 1950s, while investigating rabbits’ sense of smell by recording the activity of their brain cells, the scientist Lord Adrian noticed something curious. As his team mixed up odours of increasing strength, to see at what point the rabbits’ neurons fired in response, they found the critical threshold appeared around the same point that they were able to smell the odour themselves: in other words, this suggested that the smell had become noticeable to animal and man at the same time.
On publication of the research, Lord Adrian mentioned his observation, but it didn’t provoke a serious response, presumably because informed scientists knew that the human sense of smell is generally pathetic. Everyone knew… but they knew wrong. In a new review in Science, John McGann, who runs the Rutgers Laboratory on the Neurobiology of Sensory Cognition, takes us through the historical misunderstandings to reach the truth about what the human nose knows.
Exercising self-control leaves you feeling drained. That’s what many of us in the West believe and it’s what we seem to experience – think of the fatigue after a morning spent dealing with difficult clients or focused on spreadsheets on a computer screen. But in Indian culture, there is a widespread belief that mental effort is energising – that the more concentration and self-control you expend in one situation, the more invigorated you will feel for the next challenge.
Psychology has, so far, mostly backed up our Western intuitions. Over 100 studies – nearly all conducted in the West – have shown that participants are less able to resist temptation or exercise mental focus after completing a mentally taxing task, an effect that researchers call “ego depletion”. But now a paper in the Journal of Personality and Social Psychology has tested Indian participants and it shows for the first time a “reverse ego-depletion effect” – the more difficult an initial mental task, the better participants performed on a subsequent challenge.
The failure to reproduce established psychology findings on renewed testing, including some famous effects, has been well-publicised and has led to talk of a crisis in the field. However, psychology is a vast topic and there’s a possibility that the findings from some sub-disciplines may be more robust than others, in the sense of replicating reliably, even in unfavourable circumstances, such as when the participants have been tested on the same effect before.
A new paper currently available as a preprint at PsyArXiv has tested whether this might be the case for nine key findings from cognitive psychology, related to perception, memory and learning. Rolf Zwaan at Erasumus University Rotterdam and his colleagues found that all nine effects replicated reliably. “These results represent good news for the field of psychology,” they said.
Surely creativity is about freedom. Dropping your inhibitions – maybe with the help of a few substances – and letting ideas writhe free from the unconscious unfiltered. What to make then of the research showing that creativity is associated with higher levels of executive functioning – the mind’s suite of control processes – which seem to help by inhibiting irrelevant information and combining the rest in novel ways? Does it mean you can use this mental control to make yourself perform more creatively? According to a new study in Psychology of Aesthetics, Creativity, and the Arts involving jazz pianists the answer may depend in part on your creative experience.