science
In 2012, a genetic analysis confirmed that Concetta’s enhanced color vision can be explained by a genetic quirk that causes her eyes to produce four types of cone cells, instead of the regular three which underpin colour vision in most humans. […]
Women with four cone types in their retinas are actually more common than we think. Researchers estimate that they represent as much as 12% of the female population. […] A woman has the potential to produce four cone types because she inherits two X-chromosomes. […]
The three cone types that most of us have in our retinas allow us to see millions of colours. Each cone’s membrane is packed with molecules, called opsins, which absorb lights of some wavelengths and cause the cone to send electrical signals to the brain. […]
Four cones don’t automatically grant you superior color vision. […] Only one of the seven women with four cones behaved as if she actually perceived differences between the colour mixtures that were invisible to everyone apart from her sons.
{ The Neurosphere | Continue reading }
colors, eyes, genes | December 22nd, 2015 10:31 am
In an unusual new paper, a group of German neuroscientists report that they scanned the brain of a Catholic bishop: Does a bishop pray when he prays? And does his brain distinguish between different religions? […]
Silveira et al. had the bishop perform some religious-themed tasks, but the most interesting result was that there was no detectable difference in brain activity when the bishop was praying, compared to when he was told to do nothing in particular.
{ Neuroskeptic | Continue reading }
related { How brain architecture leads to abstract thought }
photo { Steven Brahms }
neurosciences | December 17th, 2015 1:45 pm
In 1995, a team of researchers taught pigeons to discriminate between Picasso and Monet paintings. […] After just a few weeks’ training, their pigeons could not only tell a Picasso from a Monet – indicated by pecks on a designated button – but could generalise their learning to discriminate cubist from impressionist works in general. […] For a behaviourist, the moral is that even complex learning is supported by fundamental principles of association, practice and reward. It also shows that you can train a pigeon to tell a Renoir from a Matisse, but that doesn’t mean it knows a lot about art.
[…]
What is now indisputable is that different memories are supported by different anatomical areas of the brain. […] Brain imaging has confirmed the basic division of labour between so-called declarative memory, aka explicit memory (facts and events), and procedural memory, aka implicit memory (habits and skills). The neuroscience allows us to understand the frustrating fact that you have the insight into what you are learning without yet having acquired the skill, or you can have the skill without the insight. In any complex task, you’ll need both. Maybe the next hundred years of the neuroscience of memory will tell us how to coordinate them.
[…]
Chess masters have an amazing memory for patterns on the chess board – able to recall the positions of all the pieces after only a brief glance. Follow-up work showed that they only have this ability if the patterns conform to possible positions in a legal game of chess. When pieces are positioned on the board randomly, however, chess grandmasters have as poor memories as anyone else.
{ The Guardian | Continue reading }
memory | December 15th, 2015 7:14 am
In Women After All: Sex, Evolution, and the End of Male Supremacy, Melvin Konner argues that male domination is an anomaly of human history, not a natural state for the human species. Specifically, Konner suggests that male supremacy is largely an effect of an oppressive social arrangement, namely civilization, which began with the invention of agriculture when humans began to form permanent settlements. Permanent settlements enabled men to be able to accumulate resources and allowed population densities to increase mainly through higher birth rates. Higher population densities placed more intense pressure on the land’s resources. Therefore, it became necessary for men to form coalitions with neighbors to defend against intruders. Power became concentrated in the hands of a few men, leading to a stratified society where male supremacy and female subordination reigned and male violence and war intensified. Today, Konner argues that technology limits the need for the muscle and strength of men, and male domination has outlived its purpose and is maladaptive. Therefore, empowering women is the next step in human evolution. Through empowering women, equality between the sexes will be restored and man-made disasters, such as wars, sex scandals, and financial corruption, will significantly decrease or be eliminated since women (who Konner claims are less emotional than men) will be in positions of leadership and power.
{ Evolutionary Psychology | Continue reading }
evolution, flashback, theory | December 12th, 2015 9:40 am
Why do dogs tilt their heads when we talk to them?
Biologist here. Head tilting allows an animal to gain information about the vertical placement of the sound (how far up/down it is, relative to the axis of the skull). It is assumed that canids do head-tilting to try to localize a sound better. This is backed up by the fact that canids do a lot of head-tilting when hunting small prey that are hidden behind grass or snow.
Generally — as bilaterally symmetrical animals, mammals already get pretty good information on left-right placement of a sound, due to the fact that we have an ear on the left and a different ear on the right — that means we can get left/right info by things like, time of arrival of the sound at each ear, and loudness of the sound in each ear. But up/down information (how high or low the sound source is) for a sound that is coming from directly in front can be difficult to figure out. This is a challenge for a predator that is typically approaching prey that are right in front. The head tilt solves this problem by offsetting the two ears vertically so that sounds from lower down will hit the lower ear first, and will also be ever so slightly louder in the lower ear, and vice versa for sounds coming from higher up. […]
With domestic dogs looking at a human, typically they already know the sound is coming from the human; they seem to just instinctively add the head tilt when hearing a puzzling sound, even if they’re pretty sure where it’s coming from.
{ 99trumpets/reddit | Continue reading }
dogs, noise and signals, science | December 11th, 2015 8:26 am
A new study published in The Lancet, following one million middle-aged women in Britain for 10 years, finds that the widely held view that happiness enhances health and longevity is unfounded.
“Happiness and related measures of well-being do not appear to have any direct effect on mortality,” the researchers concluded. […]
Researchers decided to look into the subject because, he said, there is a widespread belief that stress and unhappiness cause disease. […]
The new study says earlier research confused cause and effect, suggesting that unhappiness made people ill when it is actually the other way around.
{ NY Times | Continue reading }
health, psychology | December 10th, 2015 2:11 pm
Penrose and many others argue from practical considerations, Godel’s theorem, and on philosophical grounds, that consciousness or awareness is non-algorithmic and so cannot be generated by a system that can be described by classical physics, such as a conventional computer, but could perhaps be generated by a system requiring a quantum (Hilbert space) description. Penrose suspects that aspects of quantum physics not yet understood might be needed to explain consciousness. In this paper we shall see that only known quantum physics is needed to explain perception.
{ James A. Donald | Continue reading }
photo { Martin Parr }
Physics, mystery and paranormal, theory | December 3rd, 2015 1:40 pm
A growing body of literature has shown that environmental exposures in the period around conception can affect the sex ratio at birth through selective attrition that favors the survival of female conceptuses. Glucose availability is considered a key indicator of the fetal environment, and its absence as a result of meal skipping may inhibit male survival.
We hypothesize that breakfast skipping during pregnancy may lead to a reduction in the fraction of male births. Using time use data from the United States we show that women with commute times of 90 minutes or longer are 20 percentage points more likely to skip breakfast. Using U.S. census data we show that women with commute times of 90 minutes or longer are 1.2 percentage points less likely to have a male child under the age of 2. Under some assumptions, this implies that routinely skipping breakfast around the time of conception leads to a 6 percentage point reduction in the probability of a male child. Skipping breakfast during pregnancy may therefore constitute a poor environment for fetal health more generally.
{ Biodemography and Social Biology | Continue reading }
photo { Ralph Eugene Meatyard, Occasion for Diriment, 1962 }
related { Determinants of online sperm donor success: How women choose }
food, drinks, restaurants, kids, science | November 24th, 2015 2:01 pm
We now have four good Darwinian reasons for individuals to be altruistic, generous or ‘moral’ towards each other. First, there is the special case of genetic kinship. Second, there is reciprocation: the repayment of favours given, and the giving of favours in ‘anticipation’ of payback. Following on from this there is, third, the Darwinian benefit of acquiring a reputation for generosity and kindness. And fourth, if Zahavi is right, there is the particular additional benefit of conspicuous generosity as a way of buying unfakeably authentic advertising.
{ Richard Dawkins | Continue reading }
photo { Todd Fisher }
evolution, theory | November 13th, 2015 2:27 pm
Can people differentiate what they know from what they do not? Several lines of research suggest that people are not always accurate judges of their knowledge and often overestimate how much they know. Research on overconfidence finds that people commonly judge the accuracy of their judgments too favorably and typically overestimate how well they perform everyday tasks relative to other people. Work on the illusion of explanatory depth demonstrates that participants tend to think they have a better understanding of how objects work (e.g., a ballpoint pen) than they can demonstrate when that understanding is put to the test.
At times, people even claim knowledge they cannot possibly have, because the object of their knowledge does not exist, a phenomenon known as overclaiming. For example, in the late 1970s, nearly a third of American respondents expressed an opinion about the “1975 Public Affairs Act” when asked about it directly, even though the act was a complete fiction. Approximately a fifth of consumers report having used products that are actually nonexistent. More recent research has asked participants to rate their familiarity with a mix of real and nonexistent concepts, names, and events in domains such as philosophy, life sciences, physical sciences, and literature. Participants reported being familiar with the real items but also, to a lesser degree, with the nonexistent ones. […]
What underlies assertions of such impossible knowledge? We found that people overclaim to the extent that they perceive their personal expertise favorably. […]
A sizable body of work on how people evaluate their own knowledge suggests that they rely not only on a direct examination of their mental contents but also on a feeling of knowing. Notably, a feeling of knowing is often only weakly predictive of actual knowledge and appears to be informed, at least in part, by top-down inferences about what should be or probably is known. We theorized that such inferences are drawn from people’s preconceived notions about their expertise, inducing a feeling of knowing that then prompts overclaiming.
{ Psychological Science | PDF }
buffoons, psychology | November 9th, 2015 5:50 am
Decades of research have shown that humans are so-called cognitive misers. When we approach a problem, our natural default is to tap the least tiring cognitive process. Typically this is what psychologists call type 1 thinking, famously described by Nobel Prize–winning psychologist Daniel Kahneman as automatic, intuitive processes that are not very strenuous.
This is in contrast to type 2 thinking, which is slower and involves processing more cues in the environment. Defaulting to type 1 makes evolutionary sense: if we can solve a problem more simply, we can bank extra mental capacity for completing other tasks. A problem arises, however, when the simple cues available are either insufficient or vastly inferior to the more complex cues at hand.
Exactly this kind of conflict can occur when someone chooses to believe a personal opinion over scientific evidence or statistics.
{ Scientific American | Continue reading }
psychology | November 3rd, 2015 2:57 pm
Past research showed that people accumulate more knowledge about other people and objects they like compared to those they dislike. More knowledge is commonly assumed to lead to more differentiated mental representations; therefore, people should perceive others they like as less similar to one another than others they dislike.
We predict the opposite outcome based on the density hypothesis; accordingly, positive impressions are less diverse than negative impressions as there are only a few ways to be liked but many ways to be disliked. Therefore, people should perceive liked others as more similar to one another than disliked others even though they have more knowledge about liked others.
Seven experiments confirm this counterintuitive prediction and show a strong association between liking and perceived similarity in person perception.
{ Journal of Experimental Social Psychology | Continue reading }
psychology, relationships | October 31st, 2015 2:21 pm
What happens to us as we accrue knowledge and experience, as we become experts in a field? Competence follows. Effortlessness follows. But certain downsides can follow too. We reported recently on how experts are vulnerable to an overclaiming error – falsely feeling familiar with things that seem true of a domain but aren’t. Now a new paper in the Journal of Experimental Social Psychology explores how feelings of expertise can lead us to be more dogmatic towards new ideas.
{ BPS | Continue reading }
buffoons, psychology | October 31st, 2015 1:11 pm
In Experiment 1 (N = 218), where female participants rated male facial attractiveness, the facilitative effect of smiling was present when judging long-term partners but absent for short-term partners. This pattern was observed for East Asians as well as for Europeans. […]
Related to this issue, Morrison et al. (2013) compared the attractiveness of faces displaying the six basic emotions (anger, disgust, fear, happiness, sadness, and surprise). Faces with a happy expression were rated to be more attractive than faces with the other emotions, but they were rated as attractive as neutral ones.
{ Evolutionary Psychology | Continue reading }
related { Transferring the expressions of one person’s face to the other in realtime }
faces, psychology, relationships | October 27th, 2015 1:32 pm
This research examines the role of alcohol consumption on self-perceived attractiveness. Study 1, carried out in a barroom (N= 19), showed that the more alcoholic drinks customers consumed, the more attractive they thought they were.
In Study 2, 94 non-student participants in a bogus taste-test study were given either an alcoholic beverage (target BAL [blood alcohol level]= 0.10 g/100 ml) or a non-alcoholic beverage, with half of each group believing they had consumed alcohol and half believing they had not (balanced placebo design). After consuming beverages, they delivered a speech and rated how attractive, bright, original, and funny they thought they were. The speeches were videotaped and rated by 22 independent judges. Results showed that participants who thought they had consumed alcohol gave themselves more positive self-evaluations. However, ratings from independent judges showed that this boost in self-evaluation was unrelated to actual performance.
{ British Journal of Psychology | PDF }
food, drinks, restaurants, psychology | October 26th, 2015 3:56 pm
Starting at age 55, our hippocampus, a brain region critical to memory, shrinks 1 to 2 percent every year, to say nothing of the fact that one in nine people age 65 and older has Alzheimer’s disease. The number afflicted is expected to grow rapidly as the baby boom generation ages. Given these grim statistics, it’s no wonder that Americans are a captive market for anything, from supposed smart drugs and supplements to brain training, that promises to boost normal mental functioning or to stem its all-too-common decline. […]
A few years back, a joint study by BBC and Cambridge University neuroscientists put brain training to the test. Their question was this: Do brain gymnastics actually make you smarter, or do they just make you better at doing a specific task? […] All subjects took a benchmark cognitive test, a kind of modified I.Q. test, at the beginning and at the end of the study. Although improvements were observed in every cognitive task that was practiced, there was no evidence that brain training made people smarter.
There was, however a glimmer of hope for subjects age 60 and above. Unlike the younger participants, older subjects showed a significant improvement in verbal reasoning, one of the components of the benchmark test, after just six weeks of brain training, so the older subjects continued in a follow-up study for a full 12 months.
Results of this follow-up study, soon to be published in a peer-reviewed journal, generally show that continued brain training helps older subjects maintain the improvement in verbal reasoning seen in the earlier study. This is good news because it suggests that brain exercise might delay some of the effects of aging on the brain.
{ NY Times | Continue reading }
brain | October 26th, 2015 12:02 pm
Experts say fakes have become one of the most vexing problems in the art market. […]
Two years ago, the center, known for its work in bioengineering, encryption and nanotechnology, set about developing a way to infuse paintings, sculptures and other artworks with complex molecules of DNA created in the lab. […]
The new approach, in its formative stage, would implant synthetic DNA, not the personal DNA of the artists, because of privacy issues and because a person’s DNA could conceivably be stolen and embedded, thus undermining the authority of such a marking protocol.
The developers said the bioengineered DNA would be unique to each item and provide an encrypted link between the art and a database that would hold the consensus of authoritative information about the work. The DNA details could be read by a scanner available to anyone in the art industry wanting to verify an object.
{ NY Times | Continue reading }
installation { Yayoi Kusama, The obliteration room, 2002-present }
art, genes, technology | October 22nd, 2015 11:40 am
Statisticians love to develop multiple ways of testing the same thing. If I want to decide whether two groups of people have significantly different IQs, I can run a t-test or a rank sum test or a bootstrap or a regression. You can argue about which of these is most appropriate, but I basically think that if the effect is really statistically significant and large enough to matter, it should emerge regardless of which test you use, as long as the test is reasonable and your sample isn’t tiny. An effect that appears when you use a parametric test but not a nonparametric test is probably not worth writing home about.
A similar lesson applies, I think, to first dates. When you’re attracted to someone, you overanalyze everything you say, spend extra time trying to look attractive, etc. But if your mutual attraction is really statistically significant and large enough to matter, it should emerge regardless of the exact circumstances of a single evening. If the shirt you wear can fundamentally alter whether someone is attracted to you, you probably shouldn’t be life partners. […]
In statistical terms, a glance at across a bar doesn’t give you a lot of data and increases the probability you’ll make an incorrect decision. As a statistician, I prefer not to work with small datasets, and similarly, I’ve never liked romantic environments that give me very little data about a person. (Don’t get me started on Tinder. The only thing I can think when I see some stranger staring at me out of a phone is, “My errorbars are huge!” which makes it very hard to assess attraction.) […]
I think there’s even an argument for being deliberately unattractive to your date, on the grounds that if they still like you, they must really like you.
{ Obsession with Regression | Continue reading }
mathematics, relationships | October 22nd, 2015 11:17 am
Neurotechnologies are “dual-use” tools, which means that in addition to being employed in medical problem-solving, they could also be applied (or misapplied) for military purposes.
The same brain-scanning machines meant to diagnose Alzheimer’s disease or autism could potentially read someone’s private thoughts. Computer systems attached to brain tissue that allow paralyzed patients to control robotic appendages with thought alone could also be used by a state to direct bionic soldiers or pilot aircraft. And devices designed to aid a deteriorating mind could alternatively be used to implant new memories, or to extinguish existing ones, in allies and enemies alike. […]
In 2005, a team of scientists announced that it had successfully read a human’s mind using functional magnetic resonance imaging (fMRI), a technique that measures blood flow triggered by brain activity. A research subject, lying still in a full-body scanner, observed a small screen that projected simple visual stimuli—a random sequence of lines oriented in different directions, some vertical, some horizontal, and some diagonal. Each line’s orientation provoked a slightly different flurry of brain functions. Ultimately, just by looking at that activity, the researchers could determine what kind of line the subject was viewing.
It took only six years for this brain-decoding technology to be spectacularly extended—with a touch of Silicon Valley flavor—in a series of experiments at the University of California, Berkeley. In a 2011 study, subjects were asked to watch Hollywood movie trailers inside an fMRI tube; researchers used data drawn from fluxing brain responses to build decoding algorithms unique to each subject. Then, they recorded neural activity as the subjects watched various new film scenes—for instance, a clip in which Steve Martin walks across a room. With each subject’s algorithm, the researchers were later able to reconstruct this very scene based on brain activity alone. The eerie results are not photo-
realistic, but impressionistic: a blurry Steve Martin floats across a surreal, shifting background.
Based on these outcomes, Thomas Naselaris, a neuroscientist at the Medical University of South Carolina and a coauthor of the 2011 study, says, “The potential to do something like mind reading is going to be available sooner rather than later.” More to the point, “It’s going to be possible within our lifetimes.”
{ Foreign Policy | Continue reading }
neurosciences | October 20th, 2015 12:47 pm
A recent Norwegian study shows that men and women react differently to various types of infidelity. Whereas men are most jealous of sexual infidelity, so-called emotional infidelity is what makes women the most jealous. Evolutionary psychology may help explain why this may be. […]
Men and women over thousands of generations have had to adapt to different challenges that are related to reproduction. Infidelity is one such challenge. A man must decide whether he really is the father of his partner’s child, and if he should choose to invest all his protection and status resources on this child. Since the dawn of time men have grappled with paternity insecurity, since fertilization occurs inside a woman’s body.
According to the evolutionary psychology explanation, men’s jealousy is an emotional reaction to signs of sexual infidelity. The jealousy serves to reduce the chances that his partner is cheating, since he then monitors her more closely.
It’s a different story for the child’s mother. She knows for sure that she is the child’s mother, but she must ensure that the child’s father will provide their offspring with food and the security and social status it needs. The greatest threat for the woman is not that the man has sex with other women, but that he spends time and resources on women other than her.
{ Medical Xpress | Continue reading }
evolution | October 8th, 2015 3:26 pm