Our brains just keep getting more complex.
Publishing their new research in Nature, an international team of scientists has created the most detailed map of the human brain ever, finding 97 never-before-seen regions in the cerebral cortex.
The researchers analyzed brain scan data from the Human Connectome Project, which is a long-term study of 1,200 young adults. From the sample, the researchers looked at the data of 210 healthy young men and women, as well as 210 controls for comparison.
In an MRI machine, the study participants had their brains scanned both at rest and while performing some simple mental tasks, like memory tests or listening to a story. The scans recorded measurements of the cerebral cortex, which is the outer layer of brain tissue that encases the brain. The region is involved in our higher brain functions, like memory, thought, language, consciousness, and senses.
The researchers then used a machine learning algorithm designed by researchers from Oxford University to identify distinct regions in the brain, detecting 180 new regions — 83 had been identified in previous research and have now been confirmed, and 97 areas had never before been seen or established in scientific literature.
"We ended up with 180 areas in each hemisphere, but we don't expect that to be the final number," explains Matthew Glasser, the study’s lead author, in a press release. “In some cases, we identified a patch of cortex that probably could be subdivided, but we couldn’t confidently draw borders with our current data and techniques.”
“In the future, researchers with better methods will subdivide that area,” he continued. “We focused on borders we are confident will stand the test of time.”
Of the newly identified brain regions, some are clearly involved in particular tasks, while others are more ambiguous. For example, a region called 55b lights up when someone hears a story, indicating that the region is involved with language.
"Another interesting area is POS2," Glasser said in an interview with Gizmodo. "This is an area that had not previously been mapped before neuroanatomically. We don't yet know what it is doing, but given its unique pattern, it will likely be something very specialised."
In fact, there were a number of brain regions that appeared to be linked to more than one kind of mental function, so further research must be done before the scientists can fully understand the relevance of the newly discovered regions.
"The brain is not like a computer that can support any operating system and run any software," neuroscientist David Van Essen, from the Washington University School of Medicine, said in the release.
"Instead, the software – how the brain works – is intimately correlated with the brain's structure – its hardware, so to speak. If you want to find out what the brain can do, you have to understand how it is organised and wired."
To find out more about the new brain mapping, watch the video below.