iq-and-crimeThe science-news website Eurekalert reports on a new study about IQ and crime, published in Psychological Science. It shows that sons’ IQ levels are linked to their fathers’ criminal history.

Sons whose fathers have criminal records tend to have lower cognitive abilities than sons whose fathers have no criminal history, data from over 1 million Swedish men show. The research, conducted by scientists in Sweden and Finland, indicates that the link is not directly caused by fathers’ behavior but is instead explained by genetic factors that are shared by father and son.”

” ‘Perhaps most surprising was the clear gradient seen in the magnitude of the association with sons’ cognitive ability by severity of fathers’ criminality: The more severe crimes the father had committed, the poorer was the sons’ cognitive performance,’ explains [lead researcher Antti] Latvala.”

exercise-and-iqA recent article in the New York Times asks whether exercise actually increases cognition, or whether the correlations between the two are merely a placebo effect.

Short answer?

“The results from our study suggest that the benefits of aerobic exercise are not a placebo effect,” said Cary Stothart, a graduate student in cognitive psychology at Florida State University, who led the study.

…the findings are strong enough to suggest that exercise really does change the brain and may, in the process, improve thinking, Mr. Stothart said.

iq and schizophreniaA new study in the American Journal of Psychiatry (AJP in Advance, November 2014) has found that IQ and schizophrenia are closely linked, across the entire IQ range. On average, a 1-point lower IQ increases the risk of schizophrenia by 3.8%;  this association was strongest in the lower IQ range.

Likewise, “genetic susceptibility for schizophrenia had a much stronger impact on risk of illness for those with low than high intelligence,” the study found. “The IQ-genetic liability interaction arose largely from IQ differences between close relatives.”

The subjects of the study were 1.2 million Swedish males born between 1951 and 1975, whose IQs were measured at ages 18–20.

The study also found that the lower IQs were not caused by the onset of schizophrenia itself (i.e. “insidious onset“), and that there was no evidence of a link between genius and schizophrenia. Previous studies have found that such a link does indeed exist.

brain-trainingAs Todd Essig reports at Forbes, despite $1.3 billion that Americans spend on brain training games, a group of almost 100 leading brain scientists recently published a document that they’ve called “A Consensus on the Brain Training Industry from the Scientific Community.”

Their main finding is that brain training games may improve your gaming skills, but not your IQ. In other words, the skills that these games improve do not transfer broadly to other skills. And to the extent that they do transfer at all, they certainly do not transfer to boosting general intelligence.

As the signatories write: “The strong consensus of this group is that the scientific literature does not support claims that the use of software-based ‘brain games’ alters neural functioning in ways that improve general cognitive performance in everyday life, or prevent cognitive slowing and brain disease.”

That may mean more bad news for the brain training business, but evidence for the benefits of brain zapping (e.g. tDCS) continues to accumulate, with now even CNN doing an obligatory article about it.


molding-iqMore evidence from Florida State University’s Kevin Beaver that parents do not and indeed cannot influence their children’s IQ levels.

As FSU ‘s news site reports, activities like reading bedtime stories and eating nightly dinners together can indeed help to enhance kids’ social skills. But alas, they do not “have any detectable influence on children’s intelligence later in life.”

Of course, that doesn’t mean that how parents choose to raise their children is meaningless. But, as Beaver told the FSU news site, “the way you parent a child is not going to have a detectable effect on their IQ as long as that parenting is within normal bounds.”

As the research paper itself says, “the results of these statistical models indicate that family and parenting characteristics are not significant contributors to variation in IQ scores.”

This isn’t exactly news; author and researcher Judith Rich Harris drew the much same conclusion in her 1998 classic “The Nurture Assumption“.