the latest news from Psychology sites
Mon, 20 Oct 2014 See-through sensors open new window into the brain
Developing invisible implantable medical sensor arrays, a team of engineers has overcome a major technological hurdle in researchers’ efforts to understand the brain. The team has now described its technology, which has applications in fields ranging from neuroscience to cardiac care and even contact lenses.
Mon, 20 Oct 2014 Sport in old age can stimulate brain fitness, but effect decreases with advancing age
Physical exercise in old age can improve brain perfusion as well as certain memory skills, say neuroscientists who studied men and women aged between 60 and 77. In younger individuals regular training on a treadmill tended to improve cerebral blood flow and visual memory. However, trial participants who were older than 70 years of age tended to show no benefit of exercise.
Mon, 20 Oct 2014 Why your brain makes you reach for junk food
Will that be a pizza for you or will you go for a salad? Choosing what you eat is not simply a matter of taste, conclude scientists in a new study. As you glance over a menu or peruse the shelves in a supermarket, your brain is making decisions based more on a food's caloric content.
Mon, 20 Oct 2014 Brain activity provides evidence for internal 'calorie counter'
As you think about how a food will taste and whether it's nutritious, an internal calorie counter of sorts is also evaluating each food based on its caloric density, according to findings from a new neuroimaging study.
Mon, 20 Oct 2014 New antidepressant: Rapid agent restores pleasure-seeking ahead of other antidepressant action
A drug being studied as a fast-acting mood-lifter restored pleasure-seeking behavior independent of -- and ahead of -- its other antidepressant effects. Within 40 minutes after a single infusion of ketamine, treatment-resistant depressed bipolar disorder patients experienced a reversal of a key symptom -- loss of interest in pleasurable activities -- which lasted up to 14 days. Brain scans traced the agent's action to boosted activity in areas at the front and deep in the right hemisphere of the brain.
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". I'm paraphrasing Billy's response to your white lie about the toy shop.
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."
Brosseau-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
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.
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."
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
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.
2014-10-17 "Place cells" discovered in the rat brain
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.
O'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.
Wed, 20 Jan 2010 Cognitive Daily Closes Shop after a Fantastic Five-Year Run
Five years ago today, we made the first post that would eventually make its way onto a blog called Cognitive Daily. We thought we were keeping notes for a book, but in reality we were helping build a network that represented a new way of sharing psychology with the world. Cognitive Daily wasn’t the first…
Wed, 20 Jan 2010 Both musicians and non-musicians can perceive bitonality
Take a listen to this brief audio clip of “Unforgettable.” Aside from the fact that it’s a computer-generated MIDI performance, do you hear anything unusual? If you’re a non-musician like me, you might not have noticed anything. It sounds basically like the familiar song, even though the synthesized sax isn’t nearly as pleasing as the…
Thu, 14 Jan 2010 Synesthesia and the McGurk effect
We’ve discussed synesthesia many times before on Cognitive Daily — it’s the seemingly bizarre phenomenon when one stimulus (e.g. a sight or a sound) is experienced in multiple modalities (e.g. taste, vision, or colors). For example, a person might experience a particular smell whenever a given word or letter is seen or heard. Sometimes particular…