“More Complex than a Galaxy” –New Insights into the Human Brain

        Active_brain

“Consider the human brain,” says the physicist Sir Roger Penrose. “If you look at the entire physical cosmos, our brains are a tiny, tiny part of it. But they’re the most perfectly organized part. Compared to the complexity of a brain, a galaxy is just an inert lump.”

In a new study, scientists argue that many of our high-level abilities are carried out by more extensive brain networks linking many different areas of the brain. They suggest it may be the structure of these extended networks more than the size of any isolated brain region that is critical for cognitive functioning. The frontal lobes in humans vs. other species are not — as previously thought — disproportionately enlarged relative to other areas of the brain, according to a study by Durham and Reading universities.

It concludes that the size of our frontal lobes — an area in the brain of mammals located at the front of each cerebral hemisphere — cannot solely account for humans’ superior cognitive abilities.

The study also suggest that supposedly more “primitive” areas, such as the cerebellum, were equally important in the expansion of the human brain. These areas may therefore play unexpectedly important roles in human cognition and its disorders, such as autism and dyslexia, say the researchers.

The Durham and Reading researchers, funded by The Leverhulme Trust, analyzed data sets from previous animal and human studies using phylogenetic (“evolutionary family tree”) methods, and found consistent results across all their data. They used a new method to look at the speed with which evolutionary change occurred, concluding that the frontal lobes did not evolve especially fast along the human lineage after it split from the chimpanzee lineage.

Human brains share a consistent genetic blueprint and possess enormous biochemical complexity. The same basic functional elements are used throughout the cortex and understanding how one area works in detail will uncover fundamentals that apply to the other areas as well, according to an earlier study completed by scientists at the Allen Institute for Brain Science.

Human brains share a consistent genetic blueprint, and possess enormous biochemical complexity, they said, based on the first deep and large-scale analysis of the vast data set publicly available in the Allen Human Brain Atlas. Among other findings, these data show that 84% of all genes are expressed somewhere in the human brain and in patterns that are substantially similar from one brain to the next.