When a healthy person watches a smoothly moving object (say, an airplane crossing the sky), she tracks the plane with a smooth, continuous eye movement to match its displacement. This action is called smooth pursuit. But smooth pursuit isn’t smooth for most patients with schizophrenia. Their eyes often fall behind and they make a series of quick, tiny jerks to catch up or even dart ahead of their target. For the better part of a century, this movement pattern would remain a mystery. But in recent decades, scientific discoveries have lead to a better understanding of smooth pursuit eye movements.

{ Garden of the Mind | Continue reading }

Animals living in marine environments keep to their schedules with the aid of multiple independent—and, in at least some cases, interacting—internal clocks. […] Multiple clocks—not just the familiar, 24-hour circadian clock—might even be standard operating equipment in animals.

{ EurekAlert | Continue reading }

photo { Thomas Prior }

Subjective experience of time is just that—subjective. Even individual people, who can compare notes by talking to one another, cannot know for certain that their own experience coincides with that of others. But an objective measure which probably correlates with subjective experience does exist. It is called the critical flicker-fusion frequency, or CFF, and it is the lowest frequency at which a flickering light appears to be a constant source of illumination. It measures, in other words, how fast an animal’s eyes can refresh an image and thus process information.

For people, the average CFF is 60 hertz (ie, 60 times a second). This is why the refresh-rate on a television screen is usually set at that value. Dogs have a CFF of 80Hz, which is probably why they do not seem to like watching television. To a dog a TV programme looks like a series of rapidly changing stills.

Having the highest possible CFF would carry biological advantages, because it would allow faster reaction to threats and opportunities. Flies, which have a CFF of 250Hz, are notoriously difficult to swat. A rolled up newspaper that seems to a human to be moving rapidly appears to them to be travelling through treacle.

{ The Economist | Continue reading }

photo { Paul Andrews }

Lying well is hard — but not in the way you might think.

We usually look for nervousness as one of the signs of lying. Like the person is worried about getting caught. But that’s actually a weak predictor.

Some people are so confident they don’t fear getting caught. Others are great at hiding it.

Some get nervous when questioned so you get false positives. And others are lying to themselves — so they show no signs of deliberate deception.

So lying isn’t necessarily hard in terms of stress. But it is hard in terms of “cognitive load.” What’s that mean?

Lying is hard because it makes you think. You need to think up the lies. That’s extra work.

Looking for nervousness can be a wild goose chase. Looking for signs of thinking hard can be a great strategy.

[…]

They tend not to move their arms and legs so much, cut down on gesturing, repeat the same phrases, give shorter and less detailed answers, take longer before they start to answer, and pause and hesitate more. In addition, there is also evidence that they distance themselves from the lie, causing their language to become more impersonal. As a result, liars often reduce the number of times that they say words such as “I,” “me,” and “mine,” and use “him” and “her” rather than people’s names. Finally, is increased evasiveness, as liars tend to avoid answering the question completely, perhaps by switching topics or by asking a question of their own.

To detect deception, forget about looking for signs of tension, nervousness, and anxiety. Instead, a liar is likely to look as though they are thinking hard for no good reason, conversing in a strangely impersonal tone, and incorporating an evasiveness that would make even a politician or a used-car salesman blush.

{ Barking Up The Wrong Tree | Continue reading }

Hyperlink cinema uses cinematic devices such as flashbacks, interspersing scenes out of chronological order, split screens and voiceovers to create an interacting social network of storylines and characters across space and time. […]

Krems and Dunbar wondered if the social group sizes and properties of social networks in such films differ vastly from the real world or classic fiction. They set out to see if the films can side-step the natural cognitive constraints that limit the number and quality of social relationships people can generally manage. Previous studies showed for instance that conversation groups of more than four people easily fizzle out. Also, Dunbar and other researchers found that someone can only maintain a social network of a maximum of 150 people, which is further layered into 4 to 5 people (support group), 12 to 15 people (sympathy group), and 30 to 50 people (affinity group).

Twelve hyperlink films and ten female interest conventional films as well as examples from the real world and classical fiction were therefore analyzed. Krems and Dunbar discovered that all examples rarely differed and all followed the same general social patterns found in the conventional face-to-face world. Hyperlink films had on average 31.4 characters that were important for the development of plot, resembling the size of an affinity group in contemporary society. Their cast lists also featured much the same number of speaking characters as a Shakespeare play (27.8 characters), which reflects a broader, less intimate sphere of action. Female interest films had 20 relevant characters on average, which corresponds with the sympathy group size and mimics female social networks in real life.

{ Springer | Continue reading }

From biology class to “C.S.I.,” we are told again and again that our genome is at the heart of our identity. Read the sequences in the chromosomes of a single cell, and learn everything about a person’s genetic information.

But scientists are discovering that […] it’s quite common for an individual to have multiple genomes. Some people, for example, have groups of cells with mutations that are not found in the rest of the body. Some have genomes that came from other people. […]

In 1953, a British woman donated a pint of blood. It turned out that some of her blood was Type O and some was Type A. The scientists who studied her concluded that she had acquired some of her blood from her twin brother in the womb, including his genomes in his blood cells.

Chimerism, as such conditions came to be known, seemed for many years to be a rarity. But “it can be commoner than we realized,” said Dr. Linda Randolph, a pediatrician at Children’s Hospital in Los Angeles.

Twins can end up with a mixed supply of blood when they get nutrients in the womb through the same set of blood vessels. In other cases, two fertilized eggs may fuse together. […] Women can also gain genomes from their children. After a baby is born, it may leave some fetal cells behind in its mother’s body, where they can travel to different organs and be absorbed into those tissues. […] In 2012, Canadian scientists performed autopsies on the brains of 59 women. They found neurons with Y chromosomes in 63 percent of them. The neurons likely developed from cells originating in their sons. […]

Medical researchers aren’t the only scientists interested in our multitudes of personal genomes. […] Last year, for example, forensic scientists at the Washington State Patrol Crime Laboratory Division described how a saliva sample and a sperm sample from the same suspect in a sexual assault case didn’t match.

{ NY Times | Continue reading }

First Genetic Evidence That Humans Choose Friends With Similar DNA

The discovery that friends are as genetically similar as fourth cousins has huge implications for our understanding of human evolution, say biologists.

{ The Physics arXiv Blog | Continue reading }

A team of scientists in the UK claims they’ve found evidence for alien life coming to Earth. According to their paper, published in the Journal of Cosmology (more on that in a moment) they lofted a balloon to a height of 22-27 kilometers (13-17 miles). When they retrieved it, they found a single particle that appears to be part of a diatom, a microscopic plant. This, they claim, is evidence of life coming from space. […]

The team publishing this paper includes […] a man who has claimed, time and again, to have found diatoms in meteorites. However, his previous claims have been less than convincing: The methodology was sloppy, the conclusions were not at all supported by the evidence, and heck, he hadn’t even established that the rocks they found were in fact meteorites. He also has a history of seeing life from space everywhere based on pretty thin evidence.

Moreover, this team published their results in the Journal of Cosmology, an online journal that doesn’t have the most discerning track record with science.

{ Slate | Continue reading }

Physicists have discovered a jewel-like geometric object that dramatically simplifies calculations of particle interactions and challenges the notion that space and time are fundamental components of reality.

The new geometric version of quantum field theory could also facilitate the search for a theory of quantum gravity that would seamlessly connect the large- and small-scale pictures of the universe.

{ Quanta | Continue reading }

By about 1900, the need for child labour had declined, so children had a good deal of free time. But then, beginning around 1960 or a little before, adults began chipping away at that freedom by increasing the time that children had to spend at schoolwork and, even more significantly, by reducing children’s freedom to play on their own, even when they were out of school and not doing homework. Adult-directed sports for children began to replace ‘pickup’ games; adult-directed classes out of school began to replace hobbies; and parents’ fears led them, ever more, to forbid children from going out to play with other kids, away from home, unsupervised. There are lots of reasons for these changes but the effect, over the decades, has been a continuous and ultimately dramatic decline in children’s opportunities to play and explore in their own chosen ways.

Over the same decades that children’s play has been declining, childhood mental disorders have been increasing.

{ Aeon | Continue reading }

For a common affliction that strikes people of every culture and walk of life, schizophrenia has remained something of an enigma. Scientists talk about dopamine and glutamate, nicotinic receptors and hippocampal atrophy, but they’ve made little progress in explaining psychosis as it unfolds on the level of thoughts, beliefs, and experiences. Approximately one percent of the world’s population suffers from schizophrenia. Add to that the comparable numbers of people who suffer from affective psychoses (certain types of bipolar disorder and depression) or psychosis from neurodegenerative disorders like Alzheimer’s disease. All told, upwards of 3% of the population have known psychosis first-hand. These individuals have experienced how it transformed their sensations, emotions, and beliefs. […]

There are several reasons why psychosis has proved a tough nut to crack. First and foremost, neuroscience is still struggling to understand the biology of complex phenomena like thoughts and memories in the healthy brain. Add to that the incredible diversity of psychosis: how one psychotic patient might be silent and unresponsive while another is excitable and talking up a storm. Finally, a host of confounding factors plague most studies of psychosis. Let’s say a scientist discovers that a particular brain area tends to be smaller in patients with schizophrenia than healthy controls. The difference might have played a role in causing the illness in these patients, it might be a direct result of the illness, or it might be the result of anti-psychotic medications, chronic stress, substance abuse, poor nutrition, or other factors that disproportionately affect patients.

One intriguing approach is to study psychosis in healthy people. […] This approach is possible because schizophrenia is a very different illness from malaria or HIV. Unlike communicable diseases, it is a developmental illness triggered by both genetic and environmental factors. These factors affect us all to varying degrees and cause all of us – clinically psychotic or not – to land somewhere on a spectrum of psychotic traits. Just as people who don’t suffer from anxiety disorders can still differ in their tendency to be anxious, nonpsychotic individuals can differ in their tendency to develop delusions or have perceptual disturbances. One review estimates that 1 to 3% of nonpsychotic people harbor major delusional beliefs, while another 5 to 6% have less severe delusions. An additional 10 to 15% of the general population may experience milder delusional thoughts on a regular basis.

{ Garden of the Mind | Continue reading }

photo { Edgar Degas, After the Bath, Woman Drying Her Back, 1896 }

Language is not the only vehicle for many aspects of thought. Many assume that without language it is impossible to think, to remember, to communicate, to have categories/plans/procedures, to have culture and to even have consciousness. Slowly it is being shown that other animals can do many of the things that used to be classed as only-with-language skills. We just do them more effectively with language.

{ Thoughts on Thoughts | Continue reading }

art { Caravaggio, The Beheading of Saint John the Baptist, 1608 }

In most parts of the world, the banking system is closely regulated and monitored by central banks and other government agencies. That’s just as it should be, you might think.

But banks have a way round this kind of regulation. For the last decade or so, it has become common practice for banks to do business in ways that don’t show up on conventional balance sheets. Before the 2008 financial crisis, for example, many investment banks financed mortgages in this way. To all intents and purposes, these transactions are invisible to regulators.

This so-called shadow banking system is huge and important. Indeed, many economists blame activities that took place in the shadow banking system for the 2008 crash.

Davide Fiaschi, an economist at the University of Pisa in Italy, and a couple of pals reveal […] that the shadow banking system is vastly bigger than anyone had imagined before. And although its size dropped dramatically after the financial crisis in 2008, it has since grown dramatically and is today significantly bigger than it was even then.

{ The Physics arXiv Blog | Continue reading }

art { Martin Honert, Group of Teachers, 2012 }

{ The Five Cognitive Distortions of People Who Get Stuff Done | PDF }

The visible universe—including Earth, the sun, other stars, and galaxies—is made of protons, neutrons, and electrons bundled together into atoms. Perhaps one of the most surprising discoveries of the 20th century was that this ordinary, or baryonic, matter makes up less than 5 percent of the mass of the universe.

The rest of the universe appears to be made of a mysterious, invisible substance called dark matter (25 percent) and a force that repels gravity known as dark energy (70 percent).

Scientists have not yet observed dark matter directly. It doesn’t interact with baryonic matter and it’s completely invisible to light and other forms of electromagnetic radiation, making dark matter impossible to detect with current instruments. […]

Dark energy is even more mysterious, and its discovery in the 1990s was a complete shock to scientists. Previously, physicists had assumed that the attractive force of gravity would slow down the expansion of the universe over time. But when two independent teams tried to measure the rate of deceleration, they found that the expansion was actually speeding up. One scientist likened the finding to throwing a set of keys up in the air expecting them to fall back down-only to see them fly straight up toward the ceiling.

Scientists now think that the accelerated expansion of the universe is driven by a kind of repulsive force generated by quantum fluctuations in otherwise “empty” space. What’s more, the force seems to be growing stronger as the universe expands. For lack of a better name, scientists call this mysterious force dark energy.

{ National Geographic | Continue reading }

When I eventually returned to my desk at Keele University School of Psychology I wondered why it was that people swear in response to pain. Was it a coping mechanism, an outlet for frustration, or what? […]

Professor Timothy Jay of Massachusetts College of Liberal Arts in the States […] has forged a career investigating why people swear and has written several books on the topic. His main thesis is that swearing is not, as is often argued, a sign of low intelligence and inarticulateness, but rather that swearing is emotional language.

{ The Pyschologist | Continue reading }

Human skin is inhabited and re-populated depending on health conditions, age, genetics, diet, the weather and climate zones, occupations, cosmetics, soaps, hygienic products and moisturizers. All these factors contribute to the variation in the types of microbes. Population of viruses, for example, can include a mixture of good ones - like bacteriophages fighting acne-causing Propionibacterium  - and bad ones  - as highly contagious Mesles. Bacterial communities include thousands of species of Actinobacteria, Bacteroidetes, Cyanobacteria, Proteobacteria, and fungi Malassezia. […]

The major odor-causing substances are sulphanyl alkanols, steroid derivatives and short volatile branched-chain fatty acids.

Most common sulphanyl alkanol in human sweat, 3-methyl-3-sulfanylhexan-1-ol is produced by bacteria in several ways. […] Besides being a major descriptor of human sweat odor,  is also present in beers.

{ Aurametrix | Continue reading }

A day on the planet Venus is longer than a year on the planet Venus.

{ Discover | Continue reading }

Why do we cry when we’re happy?

[The] almond-sized hypothalamus can’t tell the difference between being happy or sad or overwhelmed or stressed. […] All it knows is that it’s getting a strong neural signal from the amygdala, which registers our emotional reactions, and that it must, in turn, activate the autonomic nervous system.

The autonomic nervous system (the “involuntary” nervous system) is divided into two branches: sympathetic (”fight-or-flight”) and parasympathetic (”rest-and-digest”).

Acting via the hypothalamus, the sympathetic nervous system is designed to mobilize the body during times of stress. It’s why our heart rate quickens, why we sweat, why we don’t feel hungry.

The parasympathetic nervous system, on the other hand, essentially calms us back down. The parasympathetic nervous system does something funny, too. Connected to our lacrimal glands (better known as tear ducts), activation of parasympathetic receptors by the neurotransmitter acetylcholine results in tear production. […]

I distinctly remember the feelings of sudden, intense relief. Of happiness. Of weightlessness. Of my heart rate slowing and my parasympathetic nervous system taking over. And, apparently, of acetylcholine synapsing onto lacrimal gland receptors, and of tears pouring down my make-up’d cheeks.

But from a psychological standpoint—beyond the neurotransmitters and stress and hormones—why do we cry at all?

A decade-old theory by Miceli and Castelfranchi proposes that all emotional crying arises from the notion of perceived helplessness, or the idea that one feels powerless when one can’t influence what is going on around them.

{ Gaines, on Brains | Continue reading }

Some memory exercises focus on long-term memory. Two of these are called retrieval practice and elaboration. […]

One way to elaborate is to generate an explanation for why a fact or concept is true (or false). Another way is to self-explain. Simply explain to yourself how the new ideas you’re learning relate to each other, or explain how the new ideas relate to information you already know. Still another is to make a concept map. […]

Retrieval practice is the activity of recalling information you have already committed to memory. You can practice retrieving information by simply trying to recall everything you’ve read or learned about a subject. Or, you can use the self-test approach. Self-testing means that you create questions about the subject and answer them yourself. […]

A recent study published in Science magazine suggests that retrieval practice works surprisingly well. […]

1. Retrieval practice helps you remember more information than elaboration.
2. Retrieval practice helps you understand the information better than elaboration.

{ Global Cognition | Continue reading }