Stanford math professor Keith Devlin talks about two new books that call into question the entire idea of string theory.
The theory states that tiny vibrating strings make up everything, but some scientists say there is no way to prove or disprove it.
photo { Nikki Ormerod }
Tearing is not a benign secretory correlate of sadness or other emotional state, but a potent visual cue that adds meaning to human facial expression, the tear effect. Although tearing (lacrimation) provides ocular lubrication and is a response to irritation in many animals, emotional tearing may be unique to humans and does not develop until several months after birth.
This study provides the first experimental demonstration that tears are a visual signal of sadness by contrasting the perceived sadness of human facial images with tears against copies of those images that had the tears digitally removed. Tear removal produced faces rated as less sad. Anecdotal findings suggest further that tear-removal often produced faces of uncertain emotional valence, perhaps awe, concern, or puzzlement, not just less sad. Tearing signaled sadness and resolved ambiguity.
Do all animal species have built-in expiration timers? Some fish and reptiles may not, but most creatures — and especially mammals — do seem to have an inner clock that triggers every individual’s decline to frailty after the middle years of fight-flight-and-reproduction run their course. (…) The same holds true across nearly all mammalian species. Few live to celebrate their billionth pulse. (…)
Most mammals our size and weight are already fading away by age twenty or so, when humans are just hitting their stride. By eighty, we’ve had about three billion heartbeats! That’s quite a bonus.
How did we get so lucky?
Biologists figure that our evolving ancestors needed drastically extended lifespans, because humans came to rely on learning rather than instinct to create sophisticated, tool-using societies. That meant children needed a long time to develop. A mere two decades weren’t long enough for a man or woman to amass the knowledge needed for complex culture, let alone pass that wisdom on to new generations. (In fact, chimps and other apes share some of this lifespan bonus, getting about half as many extra heartbeats.)
A simple mathematical model of the brain explains the pattern of murders by a serial killer, say researchers
On 20 November 1990, Andrei Chikatilo was arrested in Rostov, a Russian state bordering the Ukraine. After nine days in custody, Chikatilo confessed to the murder of 36 girls, boys and women over a 12 year period. He later confessed to a further 20 murders, making him one of the most prolific serial killers in modern history.Today, Mikhail Simkin and Vwani Roychowdhury at the University of California, Los Angeles, release a mathematical analysis of Chikatilo’s pattern of behaviour. They say the behaviour is well characterised by a power law and that this is exactly what would be expected if Chikatilo’s behaviour is caused by a certain pattern of neuronal firing in the brain.
Their thinking is based on the fundamental behaviour of neurons. When a neuron fires, it cannot fire again until it has recharged, a time known as the refractory period.
Each neuron is connected to thousands of others. Some of these will also be ready to fire and so can be triggered by the first neuron. These in turn will be connected to more neurons and so on. So it’s easy to see how a chain reaction of firings can sweep through the brain if conditions are ripe.
But this by itself cannot explain a serial killer’s behaviour. “We cannot expect that the killer commits murder right at the moment when neural excitation reaches a certain threshold. He needs time to plan and prepare his crime,” say Simkin and Roychowdhury.
Instead, they suggest that a serial killer only commits murder after the threshold has been exceeded for a certain period of time.
They also assume that the murder has a sedative effect on the killer, causing the neuronal activity to drop below the threshold.
Climate scientists have long warned that if we continue to burn fossil fuels like coal, oil and natural gas as our dominant source of energy, the planet will warm, extreme events will increase, and we will become more vulnerable to disasters. Overall, the planet has warmed about 1.2°F over the past century. Since I was born in 1970, the United States has heated up at a pace of 0.5°F per decade. As Lemonick points out, ”Scientists know that the increasing load of greenhouse gases we’re pumping into the atmosphere doesn’t “cause” extreme weather. But it does raise the odds, just as a diet of triple bacon cheeseburgers raises the odds of heart disease.”
All weather is now born into an environment that is warmer and moister because of man-made, heat-trapping greenhouse gas pollution. Thanks in part to warmer oceans, there is 4 percent more water vapor in the atmosphere and that amount will continue to increase as the planet warms, providing more fuel for storms. Droughts, wildfires, heat waves and heavy downpours are going to become more frequent, more intense and longer lasting. In fact, we can already see this playing out in historical data.
{ Salon | Continue reading | More: Why do people still deny climate change? }
As the Intergovernmental Panel on Climate Change concluded in its most recent assessment report: “warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level.” And as data continue to pile up, the evidence gets ever stronger that human-induced emissions of greenhouse gases are the main cause of the observed warming over the past century.
But hurricanes are difficult. Climate models predict that they will become more intense. At the same time, considerable uncertainty remains. We have only about 40 years of reliable observational records, which precludes a clear determination of their variability. Given that different aspects of climate change could act to increase or decrease hurricane activity, whether or not Katrina can be ascribed to global warming is a challenge beset by difficulty.
{ Slate | Continue reading | More: When should we blame climate change for natural disasters? }
Humanity has done little to address climate change. Global emissions of carbon dioxide reached (another) all-time peak in 2010. The most recent international talks to craft a global treaty to address the problem pushed off major action until 2020. Fortunately, there’s an alternative—curbing the other greenhouse gases.
Specifically, in the case of rapid action to slow catastrophic climate change, the best alternatives appear to be: methane and black carbon (otherwise known as soot). A new economic and scientific analysis published in Science on January 13 of the benefits of cutting these two greenhouse gases finds the benefits to be manifold—from human health to increased agricultural yields.
Even better, by analyzing some 400 potential soot- and methane-emission control measures, the international team of researchers found that just 14 deliver “nearly 90 percent” of the potential benefits. Bonus: the 14 steps also restrain global warming by roughly 0.5 degree Celsius by 2050, according to computer modeling.
Are you someone who easily recognizes everyone you’ve ever met? Or maybe you struggle, even with familiar faces? It is already known that we are better at recognising faces from our own race but researchers have only recently questioned how we assimilate the information we use to recognise people.
New research by the University of Nottingham Malaysia Campus has shown that when it comes to recognizing people the Malaysian Chinese have adapted their facial recognition techniques to cope with living in a multicultural environment.
Chrystalle Tan said: “Our research has shown that Malaysian Chinese adopt a unique looking pattern which differed from both Westerners and Mainland Chinese, possibly due to the multicultural nature of the country.”
The ability to recognize different faces may have social and evolutionary advantages. Human faces provide vital information about a person’s identity and characteristics such as gender, age, health and attractiveness. Although we all have the same basic features we have our own distinguishing features and there is evidence that the brain has a specialized mental module dedicated to face processing.
Previous research by a group at Glasgow University in Scotland showed that Asians from mainland China use more holistic recognition techniques to recognise faces than Westerners.
• Chinese focus on the centre of the face in the nose area
• Westerners focus on a triangular area between the eyes and mouth
• British born Chinese use both techniques fixating predominantly around either the eyes and mouth, or the nose
photo { Christine Osinski }
Thousands of characters — letters and obscure symbols — filled the more than 100 pages of a centuries-old text that had been located in East Berlin after the end of the Cold War. No one knew what the text meant, or even what language it was in. It was a mystery that USC computer scientist Kevin Knight and two Swedish researchers sought to solve. (…)
After months of painstaking work and a few trips down the wrong path, the moment finally came when the team knew it was on to something. Out of what had been gibberish emerged one word: ceremonie — a variation of the German word for ceremony. Knight said they figured out the rest from there.
Breaking the code on the document known as the Copiale Cipher revealed the rituals and political observations of an 18th century secret German society, as well as the group’s unusual fascination with eye surgery and ophthalmology.
But the larger significance of the team’s work wasn’t necessarily the discovery, it was how they arrived at it. (…)
“You start to see patterns, then you reach the magic point where a word appears,” he said. It was then, he said, “you no longer even care what the document’s about.”
The team ran statistical analyses of 80 languages, initially believing that the code lay in the Roman letters between the symbols that dotted the pages. Using a combination of brain power and computer wizardry, they broke the code by figuring out the symbols.
photo { Darren Almond }
Three studies released Wednesday, in the journal Nature and at the American Astronomical Society’s conference in Austin, Texas, demonstrate an extrasolar real estate boom. One study shows that in our Milky Way, most stars have planets. And since there are a lot of stars in our galaxy — about 100 billion — that means a lot of planets. (…)
Confirmed planets outside our solar system — called exoplanets — now number well over 700, still-to-be-confirmed ones are in the thousands.
previously { Now, just where might this Great Filter be located? }
{ This is a GoogleMaps picture of a farm near Goldsboro in North Carolina. The two salami-colored ponds on either side are lagoons, but not the kind where you want to swim. They’re open basins full of feces. Livestock agriculture in the US produces manure on a truly titanic scale — some ~133 million tons’ dry weight per year, ~13 times more than the sanitary waste produced by the human population. | Puff the Mutant Dragon | full story }
We now have the potential to banish the genes that kill us, that make us susceptible to cancer, heart disease, depression, addictions and obesity, and to select those that may make us healthier, stronger, more intelligent. (…)
During that year, fertility clinics across the country have begun to take advantage of the technology’s latest tools. They are sending cells from embryos conceived here through in vitro fertilization (IVF) to private U.S. labs equipped to test them rapidly for an ever-growing list of genetic disorders that couples hope to avoid.
Recent breakthroughs have made it possible to scan every chromosome in a single embryonic cell, to test for genes involved in hundreds of “conditions,” some of which are clearly life-threatening while others are less dramatic and less certain – unlikely to strike until adulthood if they strike at all.
And science is far from finished. On the horizon are DNA microchips able to analyze more than a thousand traits at once, those linked not just to a child’s health but to enhancements – genes that influence height, intelligence, hair, skin and eye color and athletic ability.
photo { Loretta Lux }
In a new study from the Centre for Addiction and Mental Health (CAMH), people with schizophrenia showed greater brain activity during tests that induce a brief, mild form of delusional thinking. This effect wasn’t seen in a comparison group without schizophrenia.
“We studied a type of delusion called a delusion of reference, which occurs when people feel that external stimuli such as newspaper articles or strangers’ overheard conversations are about them,” says CAMH Scientist Dr. Mahesh Menon, adding that this type of delusion occurs in up to two-thirds of people with schizophrenia. “Then they come up with an explanation for this feeling to make sense of it or give it meaning.”
The study was an initial exploration of the theory that the overactive firing of dopamine neurons in specific brain regions is involved in converting neutral, external information into personally relevant information among people with schizophrenia. This may lead to symptoms of delusions. “We wanted to see if we could find a way to ’see’ these delusions during Magnetic Resonance Imaging scanning,” says Dr. Menon.
{ EurekAlert | Continue reading }
Schizophrenia is a mental disorder characterized by a breakdown of thought processes and by poor emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social or occupational dysfunction. The onset of symptoms typically occurs in young adulthood, with a global lifetime prevalence of about 0.3–0.7%.
Genetics, early environment, neurobiology, and psychological and social processes appear to be important contributory factors; some recreational and prescription drugs appear to cause or worsen symptoms. Current research is focused on the role of neurobiology, although no single isolated organic cause has been found. The many possible combinations of symptoms have triggered debate about whether the diagnosis represents a single disorder or a number of discrete syndromes.
Despite the etymology of the term from the Greek roots skhizein (”to split”) and phren- (”mind”), schizophrenia does not imply a “split mind” and it is not the same as dissociative identity disorder—also known as “multiple personality disorder” or “split personality”—a condition with which it is often confused in public perception.
The mainstay of treatment is antipsychotic medication, which primarily suppresses dopamine (and sometimes serotonin) receptor activity.
photo { Brian James }
Professor Trifonov analyzes the vocabulary of 123 existing definitions of life in order to provide a possible path for finding a possible minimal agreement among scientists. To this purpose, he compares from a linguistic point of view the definitions and ranks the terms used therein according to their frequency. (…)
The outcome of this analysis is a definition of life as “self-reproduction with variations.” (…)
Is “self-reproduction with changes” a good definition? Can this definition actually provide a minimal basis of consensus?
They call it “game transfer phenomenon,” or GTP. In a controversial study, they described a brief mental hiccup during which a person reacts in the real world the way they would in a game. For some people, reality itself seems to temporarily warp. Could this effect be real?
Most of us are gamers now. The stereotype of a guy living in his parents’ basement on a diet of Cheetos and soda is long gone. The average gamer is 34 years old, gainfully employed and around 40 per cent are female. They play, on average, 8 hours a week and not just on consoles; around half of the gaming activity today is on smartphones.
Still, the idea of Angry Birds spilling into reality does sound far-fetched. Indeed, if you read some of the descriptions of GTP, they can seem a little silly. After dropping his sandwich with the buttered side down, for example, one person interviewed said that he “instantly reached” for the “R2″ controller button he had been using to retrieve items within PlayStation games. “My middle finger twitched, trying to reach it,” he told the researchers. (…)
Half accused the researchers of disingenuously formalising idiosyncratic experiences reported by a small sample of 42 - that charge was countered by their subsequent study replicating the findings in 2000 gamers. The other half asked why Griffiths was rebranding a familiar finding. “They said, ‘we’ve known about this for ages’,” he recalls. “It’s called the Tetris effect.”
That term was coined in 1996 to refer to a peculiar effect caused by spending a long time moving the game’s falling blocks into place. Play long enough and you could encounter all sorts of strange hallucinatory residuals: some reported witnessing bathroom tiles trembling, for example, or a floor-to-ceiling bookcase lurching down the wall. In less extreme but far more common cases, people saw moving images at the edge of their visual field when they closed their eyes.
photo { Arthur Tress }
A new analysis of personality tests taken by 10,000 men and women in America has found there is only a 10% overlap between the sexes where they share the same kind of personalities.
(…)
Researchers, from Italy and the Manchester Business School, say the reason we think men and women are similar is that we have been using the wrong methods to assess them.
The personality test included 15 scales, collected under five headings:
Extraversion (warmth, liveliness, social boldness, privateness and self reliance.
Anxiety (emotional stability, vigilance, apprehension and tension.)
Tough-mindedness (warmth, sensitivity, abstractedness and openness to change).
Independence (dominance, social boldness, vigilance and openness to change).
Self Control (liveliness, rule-consciousness and perfectionism.)
When comparing men’s and women’s overall personality profiles using the new method very large differences between the sexes became apparent. (…)
“We believe we have made it clear that the true extent of sex differences in human personality has been consistently underestimated.”
Women scored higher than men on Sensitivity (sensitive, aesthetic, sentimental), Warmth (warm, outgoing and attentive to others) and Apprehension (apprehensive, self-doubting and worrying.)
Men outscored women on Dominance (dominant, forceful, aggressive) and Emotional Stability (emotionally stable, adaptive, mature).
Given this importance of the flavors we learn to like, it seems to me remarkable, and unfortunate, that most people are unaware that the flavors are due mostly to the sense of smell and that they arise largely from smells we detect when we are breathing out with food in our mouths. (…)
The role of retronasal smell in flavor was finally put on the map by Paul Rozin, a psychologist at the University of Pennsylvania, in an article in 1982. As he phrased it, we need to recognize that smell is not a single sense but rather a dual sense, comprising orthonasal (breathing in) and retronasal (breathing out) senses. He devised experiments to show that the perception of the same odor is actually different depending on which sense is being used. Subjects trained to recognize smells by sniffing them had difficulty recognizing them when they were introduced at the back of the mouth.
{ Neurogastronomy: How the Brain Creates Flavor and Why It Matters | Continue reading }
The brain’s ability to function can start to deteriorate as early as 45, suggests a study in the British Medical Journal.
University College London researchers found a 3.6% decline in mental reasoning in women and men aged 45-49.
Previous research had suggested that cognitive decline does not begin much before the age of 60.
photo { Larry Sultan }
Say “placebo effect” and most people think of the boost they may get from a sugar pill simply because they believe it will work. But more and more research suggests there is more than a fleeting boost to be gained from placebos.
A particular mind-set or belief about one’s body or health may lead to improvements in disease symptoms as well as changes in appetite, brain chemicals and even vision, several recent studies have found, highlighting how fundamentally the mind and body are connected.
It doesn’t seem to matter whether people know they are getting a placebo and not a “real” treatment. One study demonstrated a strong placebo effect in subjects who were told they were getting a sugar pill with no active ingredient.
A low-pitched voice in a man is associated with a litany of masculine traits: dominance, strength, greater physical size, more attractiveness to women, and so on. But new research strikes one trait off that list: virility.
An Australian study looked at male voice pitch, women’s perceptions of it, and semen quality. Their first finding was no surprise: Women like deep voices and consider them masculine.
But contrary to expectations, they also found that these men aren’t better off in the semen department. In fact, by one measure of sperm quality — sperm concentration in ejaculate — men with the attractive voices appeared to have a disadvantage.
related { Breakthrough in male fertility: scientist grow sperm in laboratory }
There are two different types of alcohol-induced blackout: en bloc, a complete loss of memory for the affected time period; and fragmentary, where bits and pieces of memories remain. The en bloc blackout is more likely to occur when a large quantity of alcohol is ingested within a small time period.
(…)
Alcohol primarily interferes with the ability to form new long–term memories, leaving intact previously established long–term memories and the ability to keep new information active in memory for brief periods. … Blackouts are much more common among social drinkers—including college drinkers—than was previously assumed, and have been found to encompass events ranging from conversations to intercourse. Mechanisms underlying alcohol–induced memory impairments include disruption of activity in the hippocampus, a brain region that plays a central role in the formation of new autobiographical memories.
(…)
Women are more susceptible to alcohol blackouts than men (and recover more slowly) because of their generally less muscular body composition, and gender differences in pharmacokinetics.
