can’t see the forest

Not such a bright guy? Neither are his little guys.

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spermiesOkay, that’s taking it a little too far. But a study from the UK Institute of Psychiatry published in the journal Intelligence claims to have found direct correlations between a man’s mental aptitude and the cleverness of his sperm.

Working with data from 425 U.S. servicemen in the Vietnam War, the research team found that, “independently of age and lifestyle, intelligence was correlated with all three measures of sperm quality – numbers, concentration, and ability to move.”

ivy_league_pennants_3480bigOther than making themselves feel better, the scientists are interested in the genetics of intelligence and how they might be related to other measures of fitness and health, such as sperminess. While the statistical links found are small, the researchers say they are valid and telling and cannot be the result of lifestyle factors; it’s not going to make a great difference in their ability to conceive, but men of above-average intelligence definitely tend to produce above-average sperm, the study says.

From BBC News:

Lead researcher Dr Rosalind Arden said: “This does not mean that men who prefer Play-Doh to Plato always have poor sperm: the relationship we found was marginal.

“But our results do support the theoretically important ‘fitness factor’ idea.

“We look forward to seeing if the results can be replicated in other data sets, with other measures of intelligence and other measures of physical health that are also strongly related to evolutionary fitness.”

Dr Allan Pacey is an expert in fertility at the University of Sheffield.

He said: “The fact that it’s possible to detect a statistical relationship between intelligence and semen quality in adult men probably says more about the co-development of brain and testicles when the man was in his mother’s womb, and therefore how well they both function in adult life, rather than suggesting that playing Sudoku can somehow stimulate more sperm to be produced.

“The improvement in semen quality with intelligence observed in this paper is small and therefore it is unlikely to have a big impact on the ability of men of different intelligences to conceive.”

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Implant Works to ‘Read Man’s Thoughts’

Posted in brain, computers, medicine, neurology, Science, technology by Curtis on 11/30/07

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For eight years, Eric Ramsay has been ‘locked in.’ Since a terrible car crash, Ramsay has been conscious but almost completely paralyzed and unable to communicate with the world around him except through eye movements.

But neuroscientists from Boston University, according to Communist Robot, have implanted an electrode in Ramsay’s brain which, they say, currently allows them to correctly record the sounds Ramsay is imagining about 80% of the time. That is, the patient merely thinks the words he would like to say, and the electrochemical signals recorded by the device are interpreted by the researchers. The implant monitors the activity of about 41 neurons located in an area of the brain which is responsible for generating speech (perhaps Broca’s area? Just an editorial guess).

Soon, the electrode will output to a computer which will play the interpreted sounds back to Ramsay in real time, allowing him to more precisely calibrate the device to the speech he is imagining.

Schizophrenia: An Unpleasant Side Effect of Natural Selection?

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bluebrain Recent studies indicate that schizophrenic conditions may stem from a genetically-triggered maladaptation involving the gene DISC1, which, according to research, has been selected for in evolution even though it contributes to schizophrenia. Compare this with sickle-cell anemia: it is caused by having two mutated copies of a certain gene, while those with just one copy of the mutation are naturally protected against malaria.

Discover Online reports:

One of the key tenets of Darwinism is that adaptations that work against the survival of a species are destined to disappear. So why does schizophrenia continue to linger on? Could it be that it confers some advantage?

For years, scientists struggled to identify an adaptive advantage that might explain schizophrenia’s persistence. Researchers from various disciplines volleyed ideas back and forth. Some argued that the genes implicated in the disease promoted creativity; others believed that schizophrenics were frustrated cult leaders—unorthodox thinkers constitutionally “engineered” to lead segments of humanity to break off from the herd, but who lacked the charisma to effect much change. None of the theories gained much traction.

New research is pointing to a different possibility: There may be no adaptive advantage provided by schizophrenia in and of itself, but rather from some genes that contribute to the disease. According to a study published in the Proceedings of the Royal Society, there is evidence that some of the gene variants associated with schizophrenia—especially a mutation in a gene called disrupted-in-schizophrenia 1 (DISC1)—have been selected for by evolution. This supports the idea that the disease may be a maladaptive combination of mutations that individually have the potential to enhance fitness. It could be a more complicated version of the familiar case of sickle cell anemia: having two mutant copies of a certain gene causes the disease, whereas having only one mutant copy provides protection against malaria.

A recent study headed up by Johns Hopkins University neuroscientists may have found what kind of process goes awry in schizophrenic brains. Researchers found that DISC1 regulates the migration of new neurons in the adult brain. When the levels of DISC1 were reduced in mice during adult neurogenesis, the newborn neurons sped up and overshot their intended targets within the hippocampus, says Xin Duan, a study collaborator. When the neurons finally reached their destinations, they forged an unusual number of connections with neighboring cells, a series of events that might give rise to the abnormal—and quite crippling—brain functions associated with schizophrenia, according to Hongjun Song, a Johns Hopkins neurologist who also worked on the study. It is possible, Song says, that further research will lead to a drug that treats schizophrenia by restoring normal neurogenesis.

So what evolutionary advantage could schizophrenia-related genes bring to people who have some of the genes but not the disease? For now, this remains one of the many open questions about this puzzling condition.