Scientists, according to a recent study, have gotten one step closer in unraveling the mystery that is the human brain. The researchers at Washington University in St Louis were able to discover 97 never-before-known areas in the human cortex, leading the total of identified regions of the cerebral cortex to 180 (with 83 already known). This newly designed map of the brain combines different imaging techniques that have allowed the brain imaging to become more defined and focused than ever before.
The human brain is a marvel. Weighing at 3 pounds, it has the ability to accomplish innumerable tasks and yet these 3 pounds still have a lot that is unexplored. Neurologists want to know how the activities of the brain associate with the way we function in this world. The psychologists want to know how the brain makes each of us unique from one another and how the brain, that makes up only 2% of the body weight, is responsible for our personalities, our behavioral quirks and our individuality. The questions, it seems, are endless and the possibilities the brain offers, limitless. This is why it’s no wonder that the fascination with the brain has been there since the beginning of scientific inquiry.
Korbinian Brodmann in the 1900’s was the first one to identify and draw 52 regions within the cortex. By 1962, Ohio in US became the birth place for Brain mapping. Back then the information gathered from brain mapping, while limited, was able to locate and minimize the neuronal activity in the brain stem. This helped researchers in finding treatment for epilepsy, hallucinations and even schizophrenia. By 2016, the progress in brain mapping has grown exponentially. The main concern regarding such mapping techniques was the lack of sharpness and focus in images, the blurred scans made it difficult to identify regions or indicate distinction between different geographical locations within the cortex.
Comparing the previously constructed maps with the new high resolution brain maps, one of the lead researchers, Dr Matthew Glasser, said: “Stars twinkle because of turbulence in the universe, but if you put a telescope in space, there’s no atmosphere so you don’t have that blurring. If you’re not aligned, it’s like twinkling. …if they are, you just get a much sharper image.”
To make the new brain images clearer, the team combined different imaging techniques together. Using 210 healthy participants, researchers used techniques such as magnetic resonance imaging (MRI), functional MRI, task based MRI and diffusion imaging. All these techniques produce images of the structures of the brain, brain activity, the connectivity of neurons in the brain as well as indicate the activity of the brain when the patient is given different tasks to perform such as listening to stories or solving a math puzzle. The research, published in Nature, then aimed to align the data that was collected onto their map of the cerebral cortex in order to identify and understand the various regions revealed.
What Do The Newly Discovered Regions Reveal?
When the researchers in Ohio understood that the neuronal activity in the brain stem was somehow linked to epileptic episodes, they were able to find a treatment for such a condition. Imagine, just as the images of the brain stem revealed this, if we are able to completely view the entire cerebral cortex and all the regions and zones it possesses, how much of the knowledge regarding the various brain disorders can we amass? The scientists through there techniques were able to, amongst the 97 new regions; discover a region now known as 55b. This is located in the frontal cortex of the brain, alongside the Broca region. When carrying out their tests, they discovered that when the participant was asked to listen to a story, the 55b region lit up on the scans. Its activation during the task performed indicated its role in the language network. This information can prove useful since it shows us that regions beyond the Broca region and Wernicke’s area, both involved in language processing, do exist.
How Has The Human Connectome Project (HCP) Helped This Research?
Before the Connectome Project, mapping of the brain usually focused on understanding everything on a cellular level, such as how cells are presented in the particular regions of the brain. The HCP, instead, wanted to allow researchers a more diversified view of the human brain. Using the imaging scans of its participants, the HCP was able to differentiate few physical properties such as corticol thickness, the connectivity pathways between different zones or regions as well as the thickness of myelin sheath (an insulation that covers neurons) along with their location of places where the thickness of myelin differed from rest.
One of the reasons the 55b region was discovered because of the difference of its myelin thickness as compared to other regions. This difference allowed the researches to understand that a geographical boundary existed in that frontal lobe and new regions were categorized and differentiated.
What Are The Implications Of This Brain Mapping Technology?
After the alignment and mapping of the cerebral cortex, the researchers wanted the results to be universal for any person who goes for an MRI scan of their brain. To ensure that the 180 regions that were observed in their 210 HCP participants were replicable in new HCP participants, they created a tool where the computer would be able to recognize and learn all the 180 regions of the cortex. The tool was able to recognize these regions in the new participants with 96.6% accuracy, indicating that the regions are present in an atypical brain of a human and therefore the applications for this discovery are universal.
The cerebral cortex, the outer layer of the brain that contains billions of neurons, is responsible for our abstract thinking, logical reasoning and more. And diseases such as Alzheimer’s are directly caused by damage to the cortex. This brain mapping, in turn, has jumpstarted the progress in treatment of such disorders by allowing scientists a greater in-depth view of the workings of the brain. Where we go from here and what more we discover, only time will tell.