2012 April 24 Tuesday
Oppositional 3 Year Olds More Likely To Gamble

Troubled children emerge pretty early.

Based on tests of over 900 individuals beginning in toddlerhood, the study found that “people who were rated at age three as being more restless, inattentive, oppositional, and moody than other three-year old children were twice as likely to grow up to have problems with gambling as adults three decades later,” says psychologist Wendy S. Slutske of University of Missouri, who conducted the study with Terrie E. Moffitt and Avshalom Caspi, both of Duke University and University College/London; and Richie Poulton of University of Otago, in Dunedin, New Zealand.

In how many other ways do these personality traits influence outcomes a few decades later? More criminality? More drug abuse? Lower educational attainment? Also, do any of these attributes become assets when paired with sufficiently high intelligence? Do brilliant oppositional people start more companies or achieve more artistically?

I hear George Thorogood singing about when he was born:

The head nurse spoke up
Said "Leave this one alone"
She could tell right away
That I was bad to the bone

By Randall Parker    2012 April 24 10:07 PM   Entry Permalink | Comments (15)
2012 April 15 Sunday
Oxytocin, Vasopressin Genetic Variants Influence Niceness

The extent you which you view the world as threatening comes partly from genetic variants of a couple of variants of neural receptors.

Of those surveyed, 711 subjects provided a sample of saliva for DNA analysis, which showed what form they had of the oxytocin and vasopressin receptors.

"The study found that these genes combined with people's perceptions of the world as a more or less threatening place to predict generosity," Poulin says.

"Specifically, study participants who found the world threatening were less likely to help others -- unless they had versions of the receptor genes that are generally associated with niceness," he says.

These "nicer" versions of the genes, says Poulin, "allow you to overcome feelings of the world being threatening and help other people in spite of those fears.

"The fact that the genes predicted behavior only in combination with people's experiences and feelings about the world isn't surprising," Poulin says, "because most connections between DNA and social behavior are complex.

When people are able to choose offspring genetic variants for brain genes will they decide to make their kids more nice, suspicious, cautious, ambitious, laid back, anxious, empathetic? When we gain the ability to genetically shape the personalities of future generations in which directions will humans evolve? Will the human race diverge into very incompatible and different personality types? Or very different yet complementary personality types? Imagine, for example, more masculine men and more feminine women. Will they have personalities that make them more compatible.

Also see my previous post Oxytocin Receptor Variant Boosts Empathy.

Also see an article about how liberals and conservatives think differently. Will they have children who are even more liberal and more conservative? Will the middle disappear because parents just won't choose genetic mixes that yield middle of the roaders?

By Randall Parker    2012 April 15 12:09 PM   Entry Permalink | Comments (2)
2010 September 19 Sunday
Brain Area Key For Introspection

If you do a lot of introspecting you probably have a big anterior prefrontal cortex behind your eyes.

A specific region of the brain appears to be larger in individuals who are good at turning their thoughts inward and reflecting upon their decisions, according to new research published in the journal Science. This act of introspection—or "thinking about your thinking"—is a key aspect of human consciousness, though scientists have noted plenty of variation in peoples' abilities to introspect.

The new study will be published in the 17 September issue of the journal Science. Science is published by AAAS, the nonprofit science society.

In light of their findings, this team of researchers, led by Prof. Geraint Rees from University College London, suggests that the volume of gray matter in the anterior prefrontal cortex of the brain, which lies right behind our eyes, is a strong indicator of a person's introspective ability. Furthermore, they say the structure of white matter connected to this area is also linked to this process of introspection.

The researchers claim to have measured introspection by asking study participants to express a probability of whether they were right for problems they had to solve. Click thru to read the details. I'm not sure their method of measuring introspection ability is a good measure of that ability.

What I'd like to know: How strong is the correlation between anterior prefrontal cortex size and IQ? Do there exist many high-IQ people who have low capacity for introspection? Are these people marked by a greater tendency to express certainty? Would the introspection ability measured by these researchers correlate with certainty that people express about their past decisions or about their positions on political questions?

By Randall Parker    2010 September 19 09:39 AM   Entry Permalink | Comments (3)
2010 August 26 Thursday
Marriage Does Not Change Personalities

Personalities of married people do not converge. Since personality types are so stable this result is not surprising. But it cuts against a mythology about marriage.

The researchers analyzed the data of 1,296 married couples, one of the largest such studies to date, said Humbad, MSU doctoral candidate in clinical psychology. The data came from the Minnesota Center for Twin and Family Research.

The researchers wanted to know if husbands and wives become more similar as the marriage progressed. They examined a host of personality characteristics and found that, in most cases, the couples did not become more alike with more years of marriage.

The conclusion: Spousal similarity is better explained by selection than gradual convergence.

The one exception to this pattern was aggression. “It makes sense if you think about it,” Humbad said. “If one person is violent, the other person may respond in a similar fashion and thus become more aggressive over time.”

The moral of the story: If your prospective mate has personality flaws you do not expect to be able to stand in the long run do not anticipate those flaws going away.

On a similar note, I am sure dogs and their owners do not become more like each other. Though with time fondness for a dog can become very strong even if their personalities are very unlike your own. This makes them different than spouses in a positive way.

By Randall Parker    2010 August 26 09:40 PM   Entry Permalink | Comments (0)
2010 August 04 Wednesday
Childhood Personalities Stable 40 Years Later

Personality traits evident to teachers of school-aged children where will present 40 years later.

Using data from a 1960s study of approximately 2,400 ethnically diverse elementary schoolchildren in Hawaii, researchers compared teacher personality ratings of the students with videotaped interviews of 144 of those individuals 40 years later.

What they discovered was surprising, said Christopher S. Nave, a doctoral candidate at UC Riverside and lead author of the paper, “On the Contextual Independence of Personality: Teachers’ Assessments Predict Directly Observed Behavior After Four Decades.” Co-authors of the paper are Ryne A. Sherman, a UCR doctoral candidate; David C. Funder, UCR professor of psychology; Sarah E. Hampson, a researcher at the Oregon Research Institute; and Lewis R. Goldberg, professor of psychology emeritus at the University of Oregon. The research was sponsored by the National Institute on Aging through a grant to the Oregon Research Institute.

“We remain recognizably the same person,” Nave said. “This speaks to the importance of understanding personality because it does follow us wherever we go across time and contexts.”

Our personalities follow us around. You could say we are stalked by our personalities. Or we are imprisoned by our personalities, doomed to play a role dictated by personality.

Kids who possessed any of 4 different traits continued to demonstrate those traits in adult life.

The researchers examined four personality attributes – verbally fluent, adaptable, impulsive and self-minimizing. They found that:

• Youngsters identified as verbally fluent – defined as unrestrained talkativeness – tended, as middle-aged adults, to display interest in intellectual matters, speak fluently, try to control the situation, and exhibit a high degree of intelligence. Children rated low in verbal fluency by their teachers were observed as adults to seek advice, give up when faced with obstacles, and exhibit an awkward interpersonal style.

• Children rated as highly adaptable – defined as coping easily and successfully with new situations – tended, as middle-aged adults, to behave cheerfully, speak fluently and show interest in intellectual matters. Those who rated low in adaptability as children were observed as adults to say negative things about themselves, seek advice and exhibit an awkward interpersonal style.

• Students rated as impulsive as adults were inclined to speak loudly, display a wide range of interests and be talkative. Those who were rated low on impulsivity were observed, as adults, to be fearful or timid, keep others at a distance and express insecurity.

• Children whose teachers rated them as having a tendency to self-minimize – defined as humble, minimizing their own importance or never showing off – as adults were likely to express guilt, seek reassurance, say negative things about themselves and express insecurity. Those who were ranked low as self-minimizing were observed as adults to speak loudly, show interest in intellectual matters and exhibit condescending behavior.

Recognize yourself in any of those traits? Recognize me? What sort of blogging personality do I have anyway?

Biology as destiny. We are who we biologically are.

“We think that personality resides within us,” Nave said. “It’s a part of us, a part of our biology. Life events still influence our behaviors, yet we must acknowledge the power of personality in understanding future behavior as well.”

Further study will expand knowledge that “one’s personality has important outcomes associated with it.” In addition, future research will “help us understand how personality is related to behavior as well as examine the extent to which we may be able to change our personality.”

Though I wonder whether the effects of drugs like Adderal cause a long term change in personality. Anyone seen evidence that some kind of long term drug use might, say, decrease impulsiveness or become less bashful?

By Randall Parker    2010 August 04 10:18 PM   Entry Permalink | Comments (22)
2010 June 22 Tuesday
Personality Linked To Sizes Of Brain Parts

If you want to turn yourself into an extravert you'll need to find a way to grow your medial orbitofrontal cortex.

Personalities come in all kinds. Now psychological scientists have found that the size of different parts of people's brains correspond to their personalities; for example, conscientious people tend to have a bigger lateral prefrontal cortex, a region of the brain involved in planning and controlling behavior.

So the people I especially like in the work place have a big lateral prefrontal cortex. Good to know. I'm going to complement certain people for their fine lateral prefrontal cortexes.

Psychologists have worked out that all personality traits can be divided into five factors, commonly called the Big Five: conscientiousness, extraversion, neuroticism, agreeableness, and openness/intellect. Colin DeYoung at the University of Minnesota and colleagues wanted to know if these personality factors correlated with the size of structures in the brain.

For the study, 116 volunteers answered a questionnaire to describe their personality, then had a brain imaging test that measured the relative size of different parts of the brain. A computer program was used to warp each brain image so that the relative sizes of different structures could be compared. Several links were found between the size of certain brain regions and personality. The research appears in Psychological Science, a journal of the Association for Psychological Science.

Imagine employers doing brain scans to spot people who are especially conscientious. What's strikes me: Some personality traits are easier to spot. Extraverts stand out. You don't need to scan brains to identify them. By contrast, conscientious people aren't as obvious.

A bigger medial orbitofrontal cortex might make you more extraverted.

For example, "Everybody, I think, has a common sense of what extraversion is – someone who is talkative, outgoing, brash," says DeYoung. "They get more pleasure out of things like social interaction, amusement parks, or really just about anything, and they're also more motivated to seek reward, which is part of why they're more assertive." That quest for reward is thought to be a leading factor in extraversion. Earlier studies had found parts of the brain that are active in considering rewards. So DeYoung and his colleagues reasoned that those regions should be bigger in people who are more extraverted. Indeed, they found that one of those regions, the medial orbitofrontal cortex – it's just above and behind the eyes – was significantly larger in study subjects with a lot of extraversion.

What I want to know: Once prospective parents gain the ability to choose genes for their offspring that influence personality development which traits will they go for? I hope future generations aren't all extraverted. I like peaceful settings and people who can shut their yaps. Agreeableness: Too many people with this trait could create too much of a herd tendency.

By Randall Parker    2010 June 22 05:53 PM   Entry Permalink | Comments (8)
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