The validity of evolutionary psychology

NEWSWEEK takes a critical look at evolutionary psychology:

Founded in the late 1980s in the ashes of sociobiology, [evolutionary psychology] asserts that behaviors that conferred a fitness advantage during the era when modern humans were evolving are the result of hundreds of genetically based cognitive “modules” preprogrammed in the brain. Since they are genetic, these modules and the behaviors they encode are heritable—passed down to future generations—and, together, constitute a universal human nature that describes how people think, feel and act, from the nightclubs of Manhattan to the farms of the Amish, from the huts of New Guinea aborigines to the madrassas of Karachi… We in the 21st century, asserts evo psych, are operating with Stone Age minds.

Over the years these arguments have attracted legions of critics who thought the science was weak and the message (what philosopher David Buller of Northern Illinois University called “a get-out-of-jail-free card” for heinous behavior) pernicious.

Can watching TV hurt children’s language development?

USA Today reports:

For every hour in front of the TV, parents spoke 770 fewer words to children, according to a study of 329 children, ages 2 months to 4 years, in the June issue of Archives of Pediatrics & Adolescent Medicine. Adults usually speak about 941 words an hour.

Children vocalized less, too, says author Dimitri Christakis of the Seattle Children’s Research Institute. In some cases, parents may have spoken less because they sat a child in front of a TV and left the room, he says. In others, parents simply zoned out themselves while watching TV with a child. Researchers didn’t note the content of the TV shows.

 

The study is available here.

New study probes relationship between poverty, life stress, and intelligence

USA Today reports:

“Family income is a strong and consistent predictor,” of test scores, school grades and education, say a Cornell University study in the current Proceedings of the National Academy of Sciences journal. “The longer the childhood exposure to poverty, the worse the achievement levels become.”

Although a “large, robust literature” stretching back more than a decade describes this observation, study authors Gary Evans and Michelle Schamberg note there is no biological explanation for it. Why does poverty have this effect?

To find an answer, the pair looked at 195 men who were part of a long-term study of rural poverty. The study included health records and income. In 2006, about 22% of all children nationwide lived below the poverty line, living on less than $21,200 for a family of four, according to the federal Department of Health and Human Services. (About 18% of people worldwide live below the international poverty line of $1 a day, according to Princeton economist Alan Krueger.)

“The proportion of early childhood spent in poverty is also significantly related to working memory,” finds the study, perhaps not surprising. But when the researchers went back and looked at the men’s health records, the relationship between poverty and memory dissolved, revealing their health — as reflected in blood pressure, obesity and stress hormone measures — are factored in. What looks like an income effect is actually a public health problem.

The Evans & Schamberg report can be accessed here.

Impact of poverty on brain development comparable to stroke, study finds

Science Daily reports:

In a study recently accepted for publication in the Journal of Cognitive Neuroscience, scientists at UC Berkeley’s Helen Wills Neuroscience Institute and the School of Public Health report that normal 9- and 10-year-olds differing only in socioeconomic status have detectable differences in the response of their prefrontal cortex, the part of the brain that is critical for problem solving and creativity.

“Kids from lower socioeconomic levels show brain physiology patterns similar to someone who actually had damage in the frontal lobe as an adult,” said Robert Knight, director of the institute and a UC Berkeley professor of psychology. “We found that kids are more likely to have a low response if they have low socioeconomic status, though not everyone who is poor has low frontal lobe response.”

Teaching ‘executive function’ to young minds

The NY Times reports:

a small group of educational and cognitive scientists now say that mental exercises of a certain kind can teach children to become more self-possessed at earlier ages, reducing stress levels at home and improving their experience in school. Researchers can test this ability, which they call executive function, and they say it is more strongly associated with school success than I.Q.

“We know that the prefrontal cortex is not fully developed until the 20s, and some people will ask, ‘Why are you trying to improve prefrontal abilities when the biological substrate is not there yet?’ ” said Adele Diamond, a professor of developmental cognitive science at the University of British Columbia in Vancouver. “I tell them that 2-year-olds have legs, too, which will not reach full length for 10 years or more — but they can still walk and run and benefit from exercise.”

The influence of Theories of Mind on metacognition

From Science Daily:

Metacognition refers to the awareness of one’s knowledge in different areas. The more comprehensive and accurate this metacognitive knowledge, the better one is able to reflect about his or her own actions and behaviors. “Theory of Mind” (ToM) deals with very young children’s understanding of mental life and the ability to estimate mental states.

A new study in the journal Mind, Brain, and Education detects a systematic link between children’s “theory of mind” as assessed in kindergarten and their metacognitive knowledge in elementary school.

Wolfgang Schneider, Ph.D., of the University of Wurzburg examined 174 children who were either three or four years of age at the beginning of the study in order to investigate the relationship between early ToM and subsequent metacognitive development. Children were tested at four measurement points, separated by a testing interval of approximately half a year.

Language abilities assessed at the ages of three or four years made significant contributions to the prediction of metamemory scores at the age of five. ToM facilitated the acquisition of metacognitive knowledge. Early ToM competencies also affected the acquisition of metacognitive vocabulary, which in turn had an impact on developmental changes in metacognitive knowledge.

ToM development is characterized by a growing insight into inferential and interpretive mental processes. Declarative metacognitive knowledge is usually scarce in young elementary children but increases considerably over the school years, predicting academic performance.

“An important reason to study metacognitive monitoring processes is because monitoring is supposed to play a central role in directing how people study,” Schneider notes. “Our research affects issues of cognitive intellectual development and can be used to develop training programs, particularly for young children, to ensure adequate metacognitive processing in educational contexts.”

Does early childhood temperment carries through to later life?

Reuters (via MSNBC.com) reports on research by Lahey et. al. regarding the correlation between an infant’s behavior (and its interactions with parents) and the child’s temperment later in life:

The study, which followed nearly 1,900 children from infancy up to age 13, found that children whose mothers gave them plenty of intellectual stimulation in the first year of life — reading to them, talking to them and taking them out of the house — were less likely to have serious behavioral problems.

At the same time, the odds of behavior problems were also linked to certain measures of the children’s temperament during infancy — such as how “fussy” they were, or whether they had a generally happy or more moody disposition.

I don’t know much about research on temperment but I note that famed Russian psychologist Lev Vygotsky argued that cognitive development is driven by one’s interactions with others; much contemporary research supports Vygotsky’s view.