Brain Scans Show how Evolution Shaped Human Brain into Being Unique
Human brain is unique in the way it processes information and has had significant changes in its structure since humans' split from monkeys some 25 million years ago. Now, brain scans have shown how significant these structural changes are in giving human brains unique networks to process and store vast amount of information.
In the study, researchers used functional Magnetic Resonance Imaging to assess levels of activity in different regions of the brain in both monkeys and humans. The study results found that although human and monkey brain had similar structures, there were at least two functional networks in the cerebral cortex of the brains of humans that were unique and not found in monkeys meaning that these networks developed as humans strayed away from their primate relatives.
"We did functional brain scans in humans and rhesus monkeys at rest and while watching a movie to compare both the place and the function of cortical brain networks. Even at rest, the brain is very active. Different brain areas that are active simultaneously during rest form so-called 'resting state' networks. For the most part, these resting state networks in humans and monkeys are surprisingly similar, but we found two networks unique to humans and one unique network in the monkey," Professor Wim Vanduffel, Neurophysiology Research Group Faculty of Medicine, KU Leuven, an one of the study authors.
The cerebral cortex, also called the gray region of the brain, is a region where most of the information is processed.
Vanduffel said that when we watch movies, out brain is actively trying to make sense of the visual and auditory signals. And, the way human brain reacts to these signals is totally different from a monkey's reaction. He added that brain structures that are present to accommodate all this information is unique to humans and that the monkey brain has got no such feature either in the cortex or elsewhere in the brain.
"Our unique brain areas are primarily located high at the back and at the front of the cortex and are probably related to specific human cognitive abilities, such as human-specific intelligence," he concluded, according to a news release.
The study is published in The Journal of Neuroscience.