CTE and its Impact on the Brain

Chronic Traumatic Encephalopathy, or CTE, is a neurologically degenerative brain disease that results from the presence of ongoing trauma to the head. Someone experiencing this disease can undergo a variety of symptoms including mood swings, depression, anxiety, memory loss, impaired judgement and overall cognitive decline. In addition to the variant manifestations of CTE, the inability to decisively determine if an individual has this disease increases the difficulty of giving a diagnosis and finding possible treatments for a patient. The only current method of diagnosis occurs through the analysis of brain tissue following the death of an individual. 

 CTE is widely known today in part due to the published cases of the disease that have affected professional football players over the years. In a 2017 study that evaluated the brains of 202 individuals who participated in various levels of football. The results were striking; of the 111 men that played professional football in their study, 110 of their brain samples indicated that they suffered with CTE. When compared to the 3 of 14 individuals who played high school football that had the disease, and the 48 of 53 individuals who played college football that were found to have CTE, the trend between the duration of trauma and the severity of the brain damage becomes increasingly clear. 

CTE, however, has been known to develop through trauma sustained from other sport and non-sport related occurrences. The first recorded case of the brain disease was made by pathologist Harrison Martland in 1928. He observed symptoms in boxers, including lack of balance, weakness of their arms and legs, and mental derangement, that match the symptoms of CTE. Following his analysis, he created the term “punch-drunk syndrome” to describe the boxers’ symptoms. Since then, brain biopsies have been seen from individuals that had sustained head injuries from sports including soccer, rugby and ice hockey, as well as brain injuries from epeliptic seizures, prolonged abuse, and from serving in the military. 

Although the disease has various situations that lead to its development, there is a commonality in the detection of all CTE cases. The presence of clusters of the p-tau protein in the brain results in the symptoms seen in patients with this brain disease. The progressiveness of CTE’s severity has been found to be correlated with the stage that the disease is within the brain. During stage one, the tau protein can be found in both the cerebral and frontal cortices, both of which are involved in the function of judgement and memory. The clusters of tau protein, therefore, lessens the regulation of tasks related to these functions. During the second stage of CTE, the concentrations of tau protein continue to increase on the cerebral cortex, which additionally causes damage to the neurons that are adjacent to that area. By the time that the third stage of this disease occurs, the tau protein reaches the amygdala, hippocampus and the entorhinal cortex, which results in the irregularities of emotion, navigation and motivation. At this stage, the deterioration of most of the cortices neurons has begun as well. At the most severe stage, stage four, the tau protein has inhabited the middle temporal lobe, which is in control of regulating functions related to both cognition and emotions.

Due to the majority of information related to CTE being through the analysis of postmortem brain discoveries, as well as the aspects of the brain’s functioning that is yet to be discovered, effective management of this brain disease for those suffering with it is multifaceted and complex. Despite this, treatment available today addresses the symptoms of CTE separately and can be effective in helping those with the disease lead more functional lives. Cognitive behavioral therapy, which allows individuals to manage their emotional irregularities, medication for the physiological effects of the disease such as headaches, and memory-focused cognitive exercises all have been proven to be beneficial for those who undergo CTE.

References:

McKee, A. C., Stein, T. D., Kiernan, P. T., & Alvarez, V. E. (2015, May). The neuropathology of chronic traumatic encephalopathy. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4526170/

Mez, J. (2017, July 25). Evaluation of Chronic Traumatic Encephalopathy in Football Players. Retrieved from https://jamanetwork.com/journals/jama/fullarticle/2645104

What is CTE? (2020, April 15). Retrieved from https://concussionfoundation.org/CTE-resources/what-is-CTE