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Chronic traumatic encephalopathy: neurodegeneration following repetitive concussive and subconcussive brain trauma


Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative disease thought to be caused, at least in part, by repetitive brain trauma, including concussive and subconcussive injuries. It is thought to result in executive dysfunction, memory impairment, depression and suicidality, apathy, poor impulse control, and eventually dementia. Beyond repetitive brain trauma, the risk factors for CTE remain unknown. CTE is neuropathologically characterized by aggregation and accumulation of hyperphosphorylated tau and TDP-43. Recent postmortem findings indicate that CTE may affect a broader population than was initially conceptualized, particularly contact sport athletes and those with a history of military combat. Given the large population that could potentially be affected, CTE may represent an important issue in public health. Although there has been greater public awareness brought to the condition in recent years, there are still many research questions that remain. Thus far, CTE can only be diagnosed post-mortem. Current research efforts are focused on the creation of clinical diagnostic criteria, finding objective biomarkers for CTE, and understanding the additional risk factors and underlying mechanism that causes the disease. This review examines research to date and suggests future directions worthy of exploration.

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Fig. 1
Fig. 2



Beta amyloid


Alzheimer’s disease


Amyotrophic lateral sclerosis


Apolipoprotein E


Amyloid precursor protein


Blood oxygen level dependent




Cerebrospinal fluid


Chronic traumatic encephalopathy


Chronic traumatic enceohalomyelopathy


Diffusion tensor imaging


Event-related potential


Functional magnetic resonance imaging




Frontotemporal dementia


Glial tangle




Microtubule-associated protein tau


Magnetic resonance imaging


Magnetic Resonance Spectroscopy


N-acetyl asparate


Neurofibrilary tangle


Neurophil thread


Post-concussion syndrome


Positron emission tomography


Single photon emission computed tomography


Susceptibility weighted imaging


TAR DNA-binding protein 43


Traumatic brain injury


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This work was supported by grants from the National Institutes of Health (P30 AG13846; R01 NS078337), as well as a grant from the National Operating Committee on Standards for Athletic Equipment, and an unrestricted gift from the National Football League.

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No authors on this paper have conflicts of interest to disclose.

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Correspondence to Robert A. Stern.

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Baugh, C.M., Stamm, J.M., Riley, D.O. et al. Chronic traumatic encephalopathy: neurodegeneration following repetitive concussive and subconcussive brain trauma. Brain Imaging and Behavior 6, 244–254 (2012).

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  • Chronic traumatic encephalopathy
  • Traumatic brain injury
  • Dementia
  • Concussion
  • Tauopathy
  • Dementia pugilistica