Thanks to a 100 million dollar grant through the White House Brain Mapping Project to the NIH, NSF, and DARPA (Defense Advanced Research Projects Agency), a dynamically new approach to how we view the brain has arisen: the CLARITY Brain Imaging Technique. With this technique, scientists are hoping to map brain connections on a large scale, visualizing how every single neuron is fired and interconnected with the other ones in the system.
Previously, researchers had only a limited understanding of individual brain tissues. Experiments done on brain tissue included one tissue slice. This method is exceedingly useful for analysis on one specific tissue from one specific region of the brain.
For instance, according Daniel Martins De-Souza, in an article published in the World Journal of Biological Psychiatry, “two-dimensional” imaging were used to view a flat piece of brain tissue, helping to identify key protein differences between patients with schizophrenia and patients without.
However, as opposed to CLARITY, this type of analysis of brain tissue is limited because it doesn’t analyze the full brain in real time. The CLARITY Protocol allows us to look at a brain more in three dimensions instead of the two dimensions mentioned earlier.
Furthermore, from personal anecdotal experience, a quick, three-dimensional brain imaging analysis would be quite useful to researchers. While volunteering as a high-school summer intern at a Rutgers University lab, I have had the privilege to be able to observe and even help out with research into the brain. It would be quite interesting to apply three-dimensional imaging of brains to the already extensive and through research on mice and other brain tissues that occurs in the lab.
The CLARITY Process adds another dimension to the field of brain imaging and analysis. With the CLARITY technique, a voltage and solution of chemicals is used to eliminate fatty tissue in post-mortem brain sample. This makes the brain tissue more transparent, allowing “detailed exploration” of “neural circuitry”. This is the first of two technical advancements that CLARITY brings.
The CLARITY also brings a second improvement to the time needed to take an image. Previous analyses of the entire brain were limited by the fact that examination of each connection in one brain would take up to 80 years to map. This new technology, called “light-sheet microscopy” uses a more advantageous viewing angle to make the CLARITY process faster. These two improvements make the CLARITY process a worthy scientific advancement for the modern day.
For those with a TBI in particular, these imaging processes can teach us how the brain “repairs” itself and moves neuronal connections and synapses from damaged parts of the brain. With the CLARITY technique, it may be possible to image, both quantitatively and qualitatively, just how adaptable an injured brain is. For example, Raju Tomer of Stanford University writes, “This protocol [CLARITY] has been successfully applied…[to] adult human brains”.
Gaining a more complete understanding of the brain, all at once, seems to be critical when attempting to understand how an injured brain works. Hopefully, with CLARITY, researchers will be able take the first step by identifying the problems which still exist in an injured brain, and subsequently, looking for targeted solutions for these injuries. Thus, we see that CLARITY acts as the catalyst for the problem-identification phase in the long-term scientific solution to not just Traumatic Brain Injury, but also to neurobiological conditions in general.