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A new study from the University of Rochester finds that there is no single advanced area of the human brain that gives it language capabilities above and beyond those of any other animal species.

Instead, humans rely on several regions of the brain, each designed to accomplish different primitive tasks, in order to make sense of a sentence.

"We're using and adapting the machinery we already have in our brains," said study coauthor Aaron Newman. "Obviously we're doing something different [from other animals], because we're able to learn language unlike any other species. But it's not because some little black box evolved specially in our brain that does only language, and nothing else."

The study – which provides a picture of language processing in the brain with unprecedented clarity – will be published in the October 16 issue of the journal Science.

"Two central mysteries of human brain function are addressed in this study: one, the way in which higher cognitive processes such as language are implemented in the brain and, two, the nature of what is perhaps the best-known region of the cerebral cortex, called Broca's area," said first author Ned T. Sahin, PhD, post-doctoral fellow in the UCSD Department of Radiology and Harvard University Department of Psychology.

The study demonstrates that a small piece of the brain can compute three different things at different times – within a quarter of a second – and shows that Broca's area doesn't just do one thing when processing language.

in’s team benefited from a brain-reading technology called intra-cranial electrophysiology, or ICE, in which electrodes are positioned inside the brain itself. It’s a medical rather than a research tool, used to precisely measure electrical activity in the brains of epileptics who don’t respond to treatment.

This tested only one type of verbal cognition, cautioned Sahin, and the focus was unavoidably narrow, but it was enough to show that Broca’s area is involved not only in translating speech, but receiving it. That role was considered specific to part of the brain called Wernicke’s area. More broadly, the findings may represent a general rule for Broca’s area, and perhaps other brain regions: Each part plays multiple roles, rather than performing a single task.

“Having at our fingertips detailed information about when and where specific gene products are expressed in the brain brings new hope for understanding how this process can go awry in schizophrenia, autism and other brain disorders,” said NIMH Director Thomas R. Insel, M.D.

Among key findings in the prefrontal cortex:Individual genetic variations are profoundly linked to expression patterns. The most similarity across individuals is detected early in development and again as we approach the end of life.Different types of related genes are expressed during prenatal development, infancy, and childhood, so that each of these stages shows a relatively distinct transcriptional identity. Three-fourths of genes reverse their direction of expression after birth, with most switching from on to off.Expression of genes involved in cell division declines prenatally and in infancy, while expression of genes important for making synapses, or connections between brain cells, increases. In contrast, genes required for neuronal projections decline after birth – likely as unused connections are pruned.By the time we reach our 50s, overall gene expression begins to increase, mirroring the sharp reversal of fetal expression changes that occur in infancy.Genetic variation in the genome as a whole showed no effect on variation in the transcriptome as a whole, despite how genetically distant individuals might be. Hence, human cortexes have a consistent molecular architecture, despite our diversity.

Among key findings:Over 90 percent of the genes expressed in the brain are differentially regulated across brain regions and/or over developmental time periods. There are also widespread differences across region and time periods in the combination of a gene’s exons that are expressed.Timing and location are far more influential in regulating gene expression than gender, ethnicity or individual variation.Among 29 modules of co-expressed genes identified, each had distinct expression patterns and represented different biological processes. Genetic variation in some of the most well-connected genes in these modules, called hub genes, has previously been linked to mental disorders, including schizophrenia and depression.Telltale similarities in expression profiles with genes previously implicated in schizophrenia and autism are providing leads to discovery of other genes potentially involved in those disorders.Sex differences in the risk for certain mental disorders may be traceable to transcriptional mechanisms. More than three-fourths of 159 genes expressed differentially between the sexes were male-biased, most prenatally. Some genes found to have such sex-biased expression had previously been associated with disorders that affect males more than females, such as schizophrenia, Williams syndrome, and autism.