Saturday, 25 October 2014

Link feast

Our pick of the best psychology and neuroscience links from the past week or so:

Brain Games Exploit Anxieties About Memory Loss For Profit – Scientists
A group of over 70 psychologists and neuroscientists has written an open letter warning that the claims of brain training companies are unsubstantiated, and that playing the games could divert people from healthier activities.

Free Journal Articles on the Psychology of Violence and Aggression
A digital give away from the publishers Psychology Press.

Beware, Playing Lots of Chess Will Shrink Your Brain!
A new study compares the brain structure of chess grandmasters and amateurs.

Coma Songs
From BBC Radio 3: A meditation on the cultural representation of comas through music, poetry and interviews with the families of people who have a suffered brain injury.

"Just Because Something Mentions the Word 'Brain' Doesn't Mean It's Necessarily Valid Neuroscience"
A video of Professor Dorothy Bishop's recent conference talk on the increasingly popular field of "educational neuroscience".

Are Women Better Decision Makers?
A round-up of recent research findings suggests that, in stressful situations, women make better decisions than men.

Brain Baloney Has No Place in the Classroom
Pete Etchells reports on a worrying new study that found strong endorsement of neuromyths by teachers around the world.

Social Anxiety: Why The Mundane Can Be Terrifying
Guardian blogger Dean Burnett with some personal reflections on extreme shyness.

The Real Crisis in Psychiatry is That There Isn’t Enough of It
President of the Royal College of Psychiatrists Simon Wesseley lampoons the idea that psychiatrists are agents of government control, and argues instead that the real problem with psychiatry is a lack of funding and services.

This is What Developing Acute Schizophrenia Feels Like
Moving, graphic first-person account of a young man's descent into a psychotic episode and his subsequent recovery.
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Post compiled by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Friday, 24 October 2014

Publication bias afflicts the whole of psychology

In the last few years the social sciences, including psychology, have been taking a good look at themselves. While incidences of fraud hit the headlines, pervasive issues are just as important to address, such as publication bias, the phenomenon where non-significant results never see the light of day thanks to editors rejecting them or savvy researchers recasting their experiments around unexpected results and not reporting the disappointments. Statistical research has shown the extent of this misrepresentation in pockets of social science, such as specific journals, but a new meta-analysis suggests that the problem may infect the entire discipline of psychology.

A team of psychologists based in Salzburg looked at “effect sizes”, which provide a measure of how much experimental variables actually change an outcome. The researchers randomly sampled the PsycINFO database to collect 1000 psychology articles across the discipline published in 2007, and then winnowed the list down to 395 by focusing only on those that used quantitative data to test hypotheses. For each main finding, the researchers extracted or calculated the effect size.

Studies with lots of participants (500 or more) had an average effect size in the moderate range r=.25. But studies with a smaller sample tended to have formidable effect sizes, as high as .48 for studies with under 50 participants. This resulted in a strong negative relationship between number of participants and size of effect, when statistically the two should be unrelated. As studies with more participants make more precise measurements, .25 is the better estimate of a typical psychology effect size, so the higher estimates suggest some sort of inflation.

The authors, led by Anton Kühberger, argue that the literature is thin on modest effect sizes thanks to the non-publication of non-significant findings (rejection by journals would be especially plausible for non-significant smaller studies), and the over-representation of spurious large effects, due to researchers retrospectively constructing their papers around surprising effects that were only stumbled across thanks to inventive statistical methods.

The analysts rejected one alternative explanation. To detect powerful effects a small sample is sufficient, so researchers who anticipate a big effect thanks to an initial "power analysis" might deliberately plan on small samples. But only 13 per cent of the papers in this report mentioned power, and the pattern of correlation in these specific papers appears no different to that found in the ones who never mention power. Moreover, the original 1000 authors were surveyed as to what they expected the relationship between effect size and sample size to be. Many respondents expected no effect, and even more expected that studies with more participants would have larger effects. This suggests that an up-front principled power analysis decision is unlikely to have been driving the main result.

Kühberger and his co-analysts recommend that in future we give more weight to how precise study findings are likely to be, by considering their sample size. One way of doing this is by reporting a statistic that takes sample size into account, the “confidence interval”, which describes effect size not as a single value but as a range that we can be confident the true effect size falls within. As we all want to maintain confidence in psychological science, it’s a recommendation worth considering (but see here for an alternative view).

_________________________________ ResearchBlogging.org

Kühberger, A., Fritz, A., & Scherndl, T. (2014). Publication Bias in Psychology: A Diagnosis Based on the Correlation between Effect Size and Sample Size PLoS ONE, 9 (9) DOI: 10.1371/journal.pone.0105825

--further reading--
Questionable research practices are rife in psychology, survey suggests
Serious power failure threatens the entire field of neuroscience
Made it! An uncanny number of psychology findings manage to scrape into statistical significance
Fake data or scientific mistake?

Post written by Alex Fradera (@alexfradera) for the BPS Research Digest.

Thursday, 23 October 2014

How reminders of money affect people's expression and perception of emotion

Bank robbers and gamblers will tell you what people are prepared to do for the sake of money. But money also has more subtle influences. Back in 2006, researchers showed that mere reminders of money made people more selfish (although note a later attempt failed to replicate this result).

In the latest research in this field, a team led by Yuwei Jiang have shown that exposing people to pictures of money, or to money-related words, reduces their emotional expressivity and makes them more sensitive to other people's expressions of emotion. The researchers think the effect occurs because money primes a business mindset, and in business the cultural norm is to conceal emotion.

There were six studies in all, involving a mixture of dozens of undergrads in Hong Kong, and dozens of US adults recruited via the Amazon Mechanical Turk website. In every case some participants were exposed to money and some weren't. The money exposure was either via looking at pictures of cash and coins, ostensibly to judge the clarity and lighting of the pictures (control participants saw pictures of sea shells, furniture or green leaves), or through rearranging words into sentences, many of which pertained to money (control participants only dealt with neutral sentences).

Being exposed to pictures of money or money-related words led participants to say they were less keen on sharing their emotions; to actually convey less negative emotion when asked to write a negative review about a product they were unhappy with; to convey less positive emotion when asked to write a description of a funny movie clip; to perceive other people's facial expressions of emotion as more intense; and to have less desire to interact with a smiley or angry person. In each case these effects were shown in comparison with control participants who were not exposed to money.

A couple of details to consider. Jiang and his colleagues said these effects weren't simply related to motivation. For example, on the writing tasks, the money condition participants wrote just as many words and for just as long as the control participants; the specific difference was that they included less emotion in their writing. Also, there were ways to reduce the effects of money. For example, when money-exposed people were told that other people's emotions were being displayed in private, they no longer rated those people's emotions as more intense - this is consistent with the idea that money primes a business mindset that has implications for the public, but not private, expression of emotion.

The researchers said their findings have several practical implications. "... if a consideration of money increases individuals' perception that the public expression of emotion is inappropriate," they explained, "it may decrease the desirability of using money as a medium of exchange when strong feelings are being conveyed." They also added that more research is needed to see if the effects they reported will apply in nations or cultures that are less commercialised than the US and Hong Kong.

_________________________________ ResearchBlogging.org

Jiang, Y., Chen, Z., & Wyer, R. (2014). Impact of money on emotional expression Journal of Experimental Social Psychology, 55, 228-233 DOI: 10.1016/j.jesp.2014.07.013

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Wednesday, 22 October 2014

Can a brain scan tell us anything about the art of creative writing?

When an accomplished creative writer gets on with their craft, their brain operates in a somewhat different way to a novice's. A new imaging study suggests that the expert approach may be more streamlined, emotionally literate, and initially unfiltered.

Katharina Erhard with her colleagues from the German universities of Greifswald and Hildesheim asked participants to read a fragment of a story, to brainstorm what could continue the narrative, and then, for two minutes, to write a continuation of the story. Their brains were scanned throughout. This is an improvement on previous studies that have simply involved participants imagining a story while lying in a scanner.

Participants were 20 experts - students on competitive creative writing courses with over 10 years experience and a weekly average of 21 hours practice - and 28 novices practicing less than an hour per week. Independent judges considered the experts' writing significantly more creative: "unmade laundry, unloved days" was how one expert closed his response to an account of a bitter bachelor killing himself in a laundry, whereas a tale of a violinist losing his instrument in the snow conjured this image: "the glacier, winding its tongue around the sounds, suddenly gulped the violin". The differences between expert and novice brain activation during the writing phase offers some tantalising clues to how such quality emerges.

In the frontal cortex, expert brains showed greater activity in areas crucial to language and goal selection, including across the inferior frontal gyri (IFG). Verbal creativity has been associated with left IFG activation many times before, but involvement of the right IFG was unexpected. The area is associated with emotional language processing, such as interpreting expressive gestures, so this may suggest that experts are attending more deeply to the emotional currents of text and their ideas. Together with recent evidence that metaphor comprehension recruits the right temporal lobe, this suggests a role for processes housed in the right hemisphere when a verbal task is more abstract and less factual.

Expert writing also involved more activation in the left caudate. This is part of the basal ganglia, long known to be critical to learning and expert performance, and seems to reflect ordinarily cortical cognitive processes becoming automatised and bundled together within the deeper brain. In this case, these may be to do with visually processing text, as the experts showed less activation in occipital areas involved in visual and perceptual processing.

One final finding: during brainstorming, expert brains showed increased activation relative to novices in several regions associated with speech production. Taking these findings together, they paint a picture of expert creative writers: ideas bubble within them, already on the road from concept to expression, readily communicable, almost rising into their throats. These are handled by neural systems streamlined to take care of the basics, while the writer devotes greater attention to the emotional interpretation of their text. It will be down to future researchers to verify or reject this characterisation - and hopefully, some great future writers to tell us about it. Maybe you.

_________________________________ ResearchBlogging.org

Erhard, K., Kessler, F., Neumann, N., Ortheil, H., & Lotze, M. (2014). Professional training in creative writing is associated with enhanced fronto-striatal activity in a literary text continuation task NeuroImage, 100, 15-23 DOI: 10.1016/j.neuroimage.2014.05.076

Post written by Alex Fradera (@alexfradera) for the BPS Research Digest.

Tuesday, 21 October 2014

Five-year-olds can see through your bravado

Imagine you wanted to lie to a five-year-old. "The toy shop is closed Billy," you say, "it always closes at 2pm on a Monday." You reason that if you make this announcement with confidence, then Billy is sure to believe you.

It's not a bad strategy. In a new study involving nearly a hundred kids aged four to five, they were more likely to believe statements made by a woman who spoke and gestured with confidence, than those made by a woman who was hesitant and uncertain. In this case, the women's comments weren't about a toy shop, they were about the names of rare animals shown in pictures to the children (including a lanternfish and an Iberian lynx). These children had no prior experience with the women, so the women's confidence was an important cue to whether they knew what they were talking about.

But the bluster strategy has a weakness. If you've lied or been inaccurate in the past, then your bravado is likely to be ineffective. The child, especially if aged 5 and upwards, will see through your confident facade and focus instead on your reputation for being wrong. "You said that about the sweet shop last week, Mummy, but when I went and checked, they were actually open. Therefore I don't believe you now".

The researchers Patricia Brosseau-Liard and her colleagues demonstrated this childhood ability by showing a new group of children short videos of two women making bold or hesitant statements about four animals the children were familiar with - including a duck and a whale. One woman was consistently confident but inaccurate, for example she said whales live in the ground. The other woman was consistently hesitant but accurate. After this experience, the children heard the same women telling them the names of four unfamiliar animals - each woman made a different claim about the correct name and the children had to choose who to trust. The women sustained the same confident or hesitant style throughout.

The four-year-olds were often swayed by the woman who had bravado, even though they'd just seen her get her facts wrong about four familiar animals. With each extra month of wisdom, however, there was a clear developmental trajectory in the sample, so that the older children were far more likely to trust the hesitant woman with a history of being right, than the confident woman with a record for being wrong.

This isn't the first time that researchers have investigated children's sensitivity to the confidence and past accuracy of speakers. But it's actually only the second study ever to look at what happens when these cues collide. "Around the time of their fifth birthday children appropriately grant greater weight to someone's prior reliability over that person's current level of confidence," the researchers said. "This form of emerging skepticism will serve them well as they navigate through a world selecting 'better' from 'worse' sources of information."
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  ResearchBlogging.orgBrosseau-Liard, P., Cassels, T., & Birch, S. (2014). You Seem Certain but You Were Wrong Before: Developmental Change in Preschoolers’ Relative Trust in Accurate versus Confident Speakers PLoS ONE, 9 (9) DOI: 10.1371/journal.pone.0108308

--further reading--
Young children trust kindness over expertise
Toddlers won't bother learning from you if you're daft

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Monday, 20 October 2014

Decades of lie detection research has been unrealistic

According to decades of psychology research, most people, including law enforcement professionals, are useless at detecting lies. But in a new paper, a team led by Tim Levine argues that nearly all previous research has been unrealistic. The field has been dominated by studies that place the "lie detector" in a passive role, tasked with spotting "tells" leaked by the liar. But this just isn't how deception detection works in real life, say Levine and his team. Rather, the interrogator interacts with the suspect and asks strategic questions to extract the truth. In this context, the researchers predicted that expert lie detection performance would be high.

To test this, they first invited 33 students to take part in a difficult quiz with cash prizes for correct answers. They played in pairs with what they thought was another student but was really an accomplice of the researchers. When the researcher left the room for a short spell, the student participants had a chance to cheat by looking at the answer sheet. Four of them cheated in this way.

After the quiz, all the students were interviewed about what had happened during the quiz. Unbeknown to the students, their questioner was an expert interrogator, qualified in the Reid Technique and a trainer of the police and military in interrogation techniques.

The interviews lasted about four minutes, during which time the questioner asked the students how they knew the answers they'd got right. They were also asked, if someone were to cheat, how they would have gone about it. They were also told that their partner would be interviewed next, and asked what they thought he/she would say. The questioner threatened an investigation if the student had cheated to sabotage the study, but told them that it wouldn't be so bad if they'd cheated for money.

All four of the cheaters confessed about their transgression before the end of the interview. There were no false confessions. Unsurprisingly perhaps, the questioner achieved 100 per cent accuracy after the interviews when asked to identify the cheaters from among the 33 interviewees.

The tapes of the interviews were then shown to 136 more student participants who were asked to identify the cheaters. They achieved 92.7 per cent accuracy. This is consistent with the idea that strategic questioning can provoke "diagnostic answers" that anyone can interpret because they reveal the truth about what happened.

A follow-up study was similar but this time there were five expert interrogators (one woman), all of them federal agents in the US. They each had different styles of questioning and the interviews varied from 3 minutes to 18 minutes. This time, 40 of the 89 students who played the quiz cheated, or their partner did (remember, they didn't know it but their partner was actually a research assistant).

During the ensuing interviews, confessions about cheating were obtained for 34 out of 40 of the cheating episodes. There were no false confessions. The interviewers' accuracy at correctly detecting whether cheating had occurred varied from 100 per cent (for three of them) to 94.7 per cent. The interviewers identified the specific true culprit (the student or their partner) in 95.5 per cent of interviews. When the video clips were played to 34 more students, these students achieved 93.6 per cent accuracy in judging whether cheating had occurred.

"These findings suggest that high levels of deception detection may be possible," the researchers said, "but require that the right questions are asked the right way in a situation where message content is useful and where the solicitation of honesty is a viable strategy."

_________________________________ ResearchBlogging.org

Levine, T., Clare, D., Blair, J., McCornack, S., Morrison, K., & Park, H. (2014). Expertise in Deception Detection Involves Actively Prompting Diagnostic Information Rather Than Passive Behavioral Observation Human Communication Research, 40 (4), 442-462 DOI: 10.1111/hcre.12032

--further reading--
Just how good are police officers at detecting liars?
Forget good cop, bad cop - here's the real psychology of two-person interrogation
Skilled liars make great lie detectors

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Friday, 17 October 2014

"Place cells" discovered in the rat brain

John O'Keefe
Image: Nobelprize.org

This month John O'Keefe, May-Britt Moser and Edvard Moser were awarded the Nobel Prize in Physiology or Medicine for their work identifying the brain's "GPS system" - the internal maps that allow us to understand our position in space. The Moser's discovery of grid cells this century built upon O'Keefe's earlier accomplishment at UCL in London, the discovery of place cells in the brain. Here, we look back to his 1971 "Short Communication" in the journal Brain Research which presented his preliminary evidence for place cells in rats.

Earlier research had suggested that damage to a rat's hippocampus (a bilateral brain structure in the temporal lobes) causes it to become confused when attempting spatial tasks. O'Keefe wanted to look in detail at what different hippocampal regions were up to when a rat moves around, specifically to see whether there was a neural system "which provides the animal with a cognitive, or spatial, map of its environment".

Together with student Jonathan Dostrovsky, O'Keefe inserted microelectrodes through the skulls of 23 rats, each arriving at a slightly different position in the hippocampus. Each rat could then explore its limited environment - a 24cm by 36cm platform - while the experimenters recorded neural activity from the electrodes.

In all, the study took recordings from 76 different positions in the hippocampus. Some turned out to fire in response to particular behaviours, such as walking, eating, or grooming; some while the rat was aware of something; some during sleep; some for no detectable reason at all. But electrodes at eight locations only gave their full response "when the rat was situated in a particular part of the testing platform facing in a particular direction" (italics in original). This was the first ever discovery that different brain cells represent unique location and orientation information.

O'Keefe and Dostrovsky attempted to find straightforward explanations for this spatial sensitivity. But eliminating sound cues (by silencing fans and other unmoving sound sources) and olfactory ones (by rotating the testing platform) had no effect on the neural activity of these eight “place cells*”. This solidified the possibility that the eight weren't responding to information arriving through the senses from "out there", but from a representation of space that existed within the brain.

Our findings "suggest that the hippocampus provides the rest of the brain with a spatial reference map," concluded O'Keefe and Dostrovsky. As explained by Hugo Spiers in next month’s Psychologist magazine, this evidence opened up investigations into spatial memory and cognition, which began to demand some kind of coordinate system feeding into the place cells themselves. That idea was finally cashed out by the Mosers, who established that the entorhinal cortex, a key interface between the hippocampus and the neocortex, contains grid cells that perform this function by encoding atop space grids of hexagons in a honeycomb fashion familiar to anyone who has played too many wargames.

A systematic investigation into the through-lines between neural activity, cognition and behaviour, the body of work by O’Keefe and the Mosers is groundbreaking, genuinely surprising, and provides fertile ground for continued exploration, not only of rats, but of ourselves: minds within bodies within space.
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  ResearchBlogging.orgO'Keefe, J., & Dostrovsky, J. (1971). The hippocampus as a spatial map. Preliminary evidence from unit activity in the freely-moving rat Brain Research, 34 (1), 171-175 DOI: 10.1016/0006-8993(71)90358-1

*note the term "place cell" was not used in this paper.

Post written by Alex Fradera (@alexfradera) for the BPS Research Digest.

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