Progress Daily

According to the FBI, in the USA, 90.1% of murderers apprehended in 2004 were male and men accounted for 82.1% of the total number arrested for violent crimes.

In 1972 an international team of psychologists launched one of the largest longitudinal studies ever conducted. The Dunedin Multidisciplinary Health and Development Study has now followed approximately 1,000 people born in the New Zealand city of Dunedin for nearly 34 years. Terrie E. Moffitt and Avshalom Caspi, have participated in the study, and have observed that those who exhibit antisocial behavior fall into two distinct groups. Most are between the ages of 13 and 15, and their delinquency stops just as quickly as it starts. A small minority, however, display antisocial behavior in childhood — in some cases as early as age five — and this conduct continues into adulthood. Among this latter group, almost all are boys. They typically share telltale traits, among them a low tolerance for frustration, deficiencies in learning social rules, attention problems, a decreased capacity for empathy, low intelligence and, most characteristic, extreme impulsiveness.

Similarly, repeat offenders — particularly those who have long prison records — seem unable to keep their aggressive urges in check. Ernest S. Barratt interviewed imprisoned criminals in Texas in 1999 and found that many inmates consistently picked fights, even though they knew that their lives would be made more difficult as a result. When asked why, many responded that they had no idea.

Among violent offenders, neuroscientists have found anatomical and physiological differences in both the limbic system and the prefrontal cortex, brain regions that are involved in the development and control of emotions.

Jordan Grafman has discovered that Vietnam War veterans who suffered damage to the prefrontal cortex tend to be more aggressive. Similarly, adult patients who have frontal brain lesions are generally more uninhibited, inappropriate and impulsive — much like people with antisocial behavior disorders. In these adult groups, however, there is no direct indication that their brain damage predisposes them to actual violence.

For children who suffer frontal brain injury, the behavioral consequences are often more dramatic, as documented Antonio R. Damasio.

Using positron-emission tomography (PET), Adrian Raine found lower levels of metabolic activity in convicted murderers’ frontal brain regions as compared with members of the general public. This difference existed only among criminals who had killed on impulse.

Raine investigated criminals who premeditate. He compared two groups of violent criminals who had antisocial personality disorders, only some of whom had faced conviction, with 23 control subjects. Raine characterized the 16 apprehended offenders as “unsuccessful psychopaths” and the 13 who evaded the law as “successful psychopaths.” An anatomical comparison using structural magnetic resonance imaging (MRI) revealed significant differences: the volume of gray matter in the prefrontal cortex was 22.3% lower among the unsuccessful offenders as compared with the control subjects. Moreover, the volume was within normal limits among those violent criminals who avoided capture. Supplemental testing showed that the frontal brains of successful psychopaths performed even better than average on a variety of neuropsychological tasks.

In the unsuccessful group of violent criminals, the hippocampi in either hemisphere differed in size, an imbalance the researchers presume arose early in brain development. This asymmetry may impair the ability of the hippocampus and amygdala to work together, so that emotional information is not processed correctly. If the prefrontal cortex then fails as the control of last resort, inappropriate verbal and physical reactions might result.

No connection appears to exist in females between a decreased frontal brain volume and psychopathological tendencies, as has been shown in the male population.

Numerous studies have linked low levels of serotonin — an often inhibitory and fear-reducing substance in the brain — to antisocial, impulsive acts by men. Studies have not confirmed the same connection in women, suggesting that the male sex hormone, testosterone, also plays a role. James Dabbs has conducted several studies demonstrating that violent criminals have higher testosterone levels than nonaggressive criminals do. Neglect and abuse in childhood may permanently reduce serotonin levels.

Biochemical differences increase the risk of violent behavior in some men but these factors are usually not enough to precipitate actual violence. It is in combination with psychosocial risk factors that a predisposing biological mix can become explosive, as numerous studies have confirmed. Such psychosocial risk factors include serious deficiencies in the early mother-child relationship, abuse in childhood, parental neglect and inconsistent parenting, as well as persistent parental conflicts, a breakup or loss in the family, parental criminality, poverty and long-term unemployment.

Mechthild Papousek has shown that intimate communication between the infant and the primary caregiver begins shortly after birth. The infant’s qualities determine the interaction just as much as the caregiver’s personality and psychological state do. A problematic early relationship can in time lead to severe developmental disorders, among them lowered impulse control, a lack of empathy and a reduced capacity for resolving conflicts.

“The Violent Brain” by Daniel Strueber, Monika Lueck and Gerhard Roth

Research (see “Long-term Effects of Cognitive Training on Everyday Functional Outcomes in Older Adults“) has shown that the benefits of the brain exercises extend well beyond the specific skills the volunteers learned. Older adults who did basic exercises followed by later sessions were 3 times as fast as those who got only the initial sessions when it came to activities of daily living, such as reacting to a road sign, looking up a number in a telephone book or checking the ingredients on a medicine bottle.

If anything there is a bigger payoff to mental than to physical exercise, because brief training sessions seem to confer enormous benefits as many as 5 years later.

The researchers divided the volunteers into four groups, including a control group that received no training. A second group was trained in reasoning skills — being asked to spot the pattern in the sequence “a, c, e, g, i,” for example — every other letter of the alphabet. A third group was taught memory skills, which involved remembering word lists and using visualizations and associations as memory aids. A fourth group was given exercises to speed up mental processing — being asked to identify an object flashed briefly on a computer screen while fighting off distractions.

Each of the groups being trained had 10 sessions, each lasting an hour to 75 minutes, and each session presented progressively more challenging problems. Compared with the control group, those who got memory training did 75% better on memory tasks five years later, those who got the reasoning training did 40% better on reasoning tasks, and those who got the speed training did 300% better than the control group.

The study tracked 2,802 healthy adults from diverse backgrounds who were, on average, 73 years old. Although it did not examine the effects of mental exercise on people who had begun to show signs of Alzheimer’s or other brain disorders, previous studies have pointed toward the conclusion that anyone can benefit.

To reap the benefits, people need to get outside their comfort zones. For someone who likes to solve crossword puzzles, it is important to make sure the puzzles get harder with time — or to start playing chess.

“Short Mental Workouts May Slow Decline of Aging Minds, Study Finds” by Shankar Vedantam

For six decades, developed nations have not fought each other, while, historically, powerful nations are the most war prone. Statistical studies show democracies typically don’t fight other democracies. Yet, democratic nations go to war about as much as other nations overall. And recent research makes clear that only the affluent democracies are less likely to fight each other. Poor democracies behave much like non-democracies.

Nations with high levels of economic freedom not only fight each other less, they go to war less often, period.

The “democratic peace” is a mirage created by the overlap between economic and political freedom.

When democracy and economic freedom are both included in a statistical model, the results reveal that economic freedom is 50 times more potent in encouraging peace. Democracy does not have a measurable impact, while nations with very low levels of economic freedom are 14 times more prone to conflict than those with very high levels.

“Future Depends on Capitalizing on Capitalist Peace” by Erik Gartzke

People are less happy when they are interacting with their children than when they are eating, exercising, shopping or watching television. An act of parenting makes most people about as happy as an act of housework. (See A survey method for characterizing daily life experience by Alan Krueger, Norbert Schwarz, etc.) Economists have consistently found that children have a small negative impact on parents’ happiness. (See “The macroeconomics of happiness” by Rafael M. DiTella, Robert MacCulloch, & Andrew Oswald.)

When we pay a lot for something, we assume it makes us happy. Given the high price we pay, it isn’t surprising that we rationalize those costs and conclude that our children must be repaying us with happiness.

“Does Fatherhood Make You Happy?” by Daniel Gilbert

If you eat slowly, you will eat less — and you will enjoy the meal more.

Dr. Kathleen Melanson had 30 young women eat a meal of ditalini with tomato and vegetable sauce, topped with Parmesan cheese, under two different conditions. Before each meal, the women had eaten a standard 400-calorie breakfast, and then fasted for four hours.

At one visit to the lab, study participants were given a large spoon and told not to pause between bites and to eat as quickly as possible. At the other, participants ate with a small spoon, which they put down after each bite, and were told to take small bites and chew each bite 15 to 20 times.

When eating quickly, the women took in an average of 646 calories in nine minutes. But when they slowed down, they consumed 579 calories in 29 minutes.

The women felt fuller and more satisfied immediately after they ate the meal and an hour later when they had consumed it slowly.

Someone who ate three leisurely meals might consume 210 fewer calories a day than someone who wolfed those meals down.

“Eating slowly really does make people eat less” by Anne Harding

Neanderthal man was a strong, large-brained, skilful big-game hunter who had survived for more than 200,000 years in the harsh European climates of the last Ice Age. But within a few thousand years of the arrival of modern humans in the continent, he was extinct.

In existing pre-agricultural societies there is a division of food-acquiring labor between men, who hunt, and women, who gather. “What’s a Mother to Do?: The Division of Labor among Neandertals and Modern Humans in Eurasia” (Current Anthropology) proposes that this division of labor happened early in the species’ history, and that it is what enabled modern humans to expand their population at the expense of Neanderthals.

Division of labor leads to greater productivity because it allows people to specialize and become very good at what they do. In the vast majority of cases among historically known and present-day foragers, men specialise in hunting big game, while women hunt smaller animals and collect plant food. In colder climes, where long winters make plant-gathering difficult or impossible for much of the year, women often specialize in making clothing and shelters.

The archaeological record shows few signs of any specialization among the Neanderthals from their appearance about 250,000 years ago to their disappearance 30,000 years ago. They did one thing almost to the exclusion of all else: they hunted big game. There are plenty of collections of bones from animals such as reindeer, horses, bison and mammoths that are associated with Neanderthals, but few remains of rabbits or tortoises. There is also little sign of preserved seeds and nuts, or of the specialized grinding stones that would have been needed to process them. And there are no bone awls or needles that would suggest that Neanderthals were skilled leather workers, despite the abundance of animal skins that their hunting would have provided.

Signs of division of labor come only with the arrival of modern humans into Europe around 40,000 years ago. That is when evidence appears of small animals being eaten routinely and plant foods being gathered. It is also when tools designed for sophisticated leather working emerge.

Division of labor probably originated in a warmer part of the world — Africa seems most likely — where plant foods could be gathered profitably all year round. But as humans brought the idea of division of labor north, the female side of the bargain gave the species a significant advantage by providing fallback foods when big game was scarce and allowing more people to inhabit a given piece of land in times of plenty.

“Mrs Adam Smith,” The Economist

Norman Borlaug: Thanks to synthetic fertilisers global cereal production tripled between 1950 and 2000, but the amount of land used increased by only 10%. The more intensively you farm the more room you have left for rainforest.

Anthony Trewavas: organic farming requires more energy per ton of food produced because yields are lower and weeds are kept at bay by ploughing.

Michael Pollan: only 1/5 of the energy associated with food production across the whole food chain is consumed on the farm: the rest goes on transport and processing.

“Fairtrade” means paying producers an above-market price for produce, provided farmers meet particular labor and production standards. This premium is passed back to the producers to spend on development programs.

Tim Harford: the low price of commodities such as coffee is due to overproduction, and ought to be a signal to producers to switch to growing other crops. Paying a guaranteed premium both prevents this signal from getting through and, by raising the average price paid for coffee, encourages more producers to enter the market. This then drives down the price of non-Fairtrade coffee even further, making non-Fairtrade farmers poorer.

“Voting with your trolley” The Economist

Cass Sunstein organized an experiment in which he invited a set of Colorado citizens from two communities - liberal Boulder and conversative Colorado Springs - to come to local universities and deliberate three divisive political topics: global warming, affirmative action and civil rights. The groups - 5-7 randomly selected citizens from the same community - had a strong tendency to become more politically polarized over the course of the discussion.

In a group setting, people will often gravitate towards a strongly stated opinion, especially if their own opinions aren’t fully formed. People find it difficult to defy the will of a group, and may polarize to avoid interpersonal conflict.

The results of the Iowa Electronic Market, where users bet real money on the outcome of local and national elections, are consistently better than the results of opinion polls, a finding that’s held true over many years of experimentation.

When people are putting money on the line - real, or imaginary - they’re more likely to be right than when they’re guessing at beans in a jar. In sufficiently flexible markets, a small number of well-informed actors can steer prices in the right direction (often making money in the process from the less well-informed).

Ethan Zuckerman’s review of Cass Sunstein’s Infotopia

For as long as pollsters have been asking the question, roughly 90% of Americans have been claiming to believe in God, and a sizeable majority believes that God takes a personal interest in their lives and intervenes to help them.

Psychology experiments reveal that people are often satisfied by empty form. When experimenters approached people who were standing in line at a photocopy machine and said, “Can I get ahead of you?” the typical answer was no. But when they added to the end of this request the words “because I need to make some copies,” the typical answer was yes. The second request used the word “because” and hence sounded like an explanation, and the fact that this explanation told them nothing that they didn’t already know was oddly irrelevant.

In another study, experimenters approached people in a library, handed them a card with a $1 coin attached, and then walked away. Some people received the card on the top, and some received the card on the bottom.

Although the two extra questions on the bottom card — “Who are we?” and “Why do we do this?” — provide no information whatsoever, they do give one the sense that puzzling questions have been posed and then answered. The people who received the bottom card were less curious and less delighted 20 minutes after receiving it than were people who received the top card because only the latter felt that something wonderful and inexplicable had happened.

Research in psychology has shown that people tend to mistake the products of random processes for the products of non-random processes but not the other way around. For example, if we tossed a coin and it came up heads five times in a row, many of us would suspect that the outcome of these flips was non-random. That’s a mistake. Because while the odds of tossing five heads in a row by random chance are not tremendous, they are not slight — roughly three in a hundred.

If we glance at a Necker cube we have the sense that we are looking across at a box that has a dot on its left inside corner. But if we stare for a few moments, the cube suddenly shifts, and we have the sense that we are looking down at a box that has a dot sitting on its lower left edge. (A more riveting version of this is here.). Experiments show that if we are rewarded for seeing the cube one way rather than the other — rewarded with a jellybean, a dollar bill, or a friendly pat on the back — our brains begin to hold on to the rewarding view, and the cube stops changing. Human brains like the most rewarding view and thus they search for and hold on to that view whenever they can.

Research suggests that people may mistakenly attribute the good fortune that is the natural product of a helpful brain to the intervention of a helpful agent. For instance, in a study done in my laboratory, female volunteers were told that they would be working on a two-person task that required them to have a teammate whom they liked and trusted. The volunteers were shown four folders, each of which contained the biography of a potential teammate. They were told that before reading the biographies they must choose a folder randomly, and that the person whose biography was in the chosen folder would be their teammate. The volunteers looked at the four folders, chose one randomly, and then read the biography they found inside. What the volunteers did not know was that the experimenter had put the same biography in all four folders, and that it was the biography of someone who was not particularly likeable or trustworthy.

As the volunteers read the biography, their brains searched for, found, and held on to the best possible view of the teammate. When volunteers finished reading their new teammate’s biography, they were given three other biographies to read, and they were then asked to rate all four of the biographies. The volunteers rated their teammate as superior to the others.

After the volunteers read and rated the biographies, the experimenter took the volunteer aside and explained that while the volunteer had been “randomly choosing” a folder, the experimenter had been using a subliminal message to try to make the volunteer choose the best possible partner. This wasn’t true but the volunteers believed it. Then the volunteers were asked: “Do you think the subliminal message had any effect on your choice of folders?” By and large, volunteers thought the subliminal message had guided their choice of folders. Although they had been given a relatively dislikeable teammate, their brains had managed to find a rewarding view of that teammate; but because they did not know that their brains deserved the credit for their good fortune, they gave the credit to a subliminal message.

The experiments described are drawn from the following papers: “The illusion of external agency,” “The mindlessness of ostensibly thoughtful action,” & “The pleasures of uncertainty.”

“The Vagaries of Religious Experience” by Daniel Gilbert

Between different neighborhoods in North London there is a 10-year variation in life expectancy for men (79.6 years in Belsize Park, 69.7 in Kilburn).

Our research shows that for people of equivalent social status, it is the area that matters. More deprivation in an area means worse health. Lower social position means worse health.

In London people classified as unskilled manual have about twice the mortality rate of top professionals. In the north-east of England, the difference in mortality is sixfold.

Our own studies confirm that poor people living in poor neighborhoods have worse health than if they lived in richer ones.

We gave respondents in a study of civil servants a drawing of a ladder representing the social hierarchy and asked them to place a cross on the rung that marked their place. As expected, the lower the grade of employment, the lower people were likely to place themselves. For people of low employment grade, the more deprived the area, the lower they ranked themselves on the social ladder. For those of low status at work, their perception of social position was enhanced by living in a more affluent area, and further diminished by living in a poor one.

In our studies, we characterised neighborhoods according to responses to a simple survey. We found that trust, tolerance and sense of attachment to the neighbourhood were strongly related to health. These links were independent of the physical infrastructure.

The links of social cohesion to health were stronger among women than men.

Ichiro Kawachi, using responses to a simple social survey, showed that the higher the income inequality of a state, the lower was the level of trust, perceived fairness, perceived helpfulness or civic engagement. He concluded that low social capital provides the mechanism that links income inequality to mortality.

“For Richer, for Poorer” by Michael Marmot