A recent traumatic brain injury study by the Boston University Center for the Study of Traumatic Encephalopathy and the Veterans Affairs Boston Healthcare System shows a link between head trauma and long-term degenerative brain disease. As reported in the New York Times, the study was conducted over a four-year period and included posthumous testing of brain samples from 85 people who had histories of repeated mild traumatic brain injury ("TBI"). The study found that 80 percent of the 85 people tested showed evidence of chronic traumatic encephalopathy ("CTE"). CTE is a degenerative and incurable disease whose symptoms include memory loss, depression, and dementia. CTE can be caused by trauma which triggers progressive degeneration of the brain tissue, including the build-up of an abnormal protein called tau. To read the study in full, click here.
The study's investigators created a four-tiered system to classify degrees of CTE. Stage 1 of the disease is characterized by headaches and loss of attention and concentration. Stage 2 involves those symptoms along with depression, explosive behavior, and short-term memory loss. Those with Stage 3 CTE have cognitive impairments and trouble with executive functions like planning and organizing. Stage 4 victims have dementia, difficulty finding words, and aggression.
TBI's occur when the brain is accelerated and then rapidly decelerated within the skull. When that occurs, the soft brain is caused to collide with the bony and pointy parts of the skull, resulting in brain damage through axonal shearing. Axonal shearing may be localized or more diffuse, and thus various parts of the brain that control different functions may be affected even if a blow lands only on one part of the head.
The effects of brain damage caused by these types of coup-contre-coup brain injuries include memory loss, cognitive deficiencies, fatigue, headaches (both migraine and tension), psychological disorders, concentration problems, and other related problems.