Traumatic brain injury or traumatic brain disease: A scientific commentary

Traumatic Brain Injury (TBI) represents a major public health burden and a major contributor to disability and death, especially in the young population. It remains one of the most challenging human conditions to classify and the non-standardized classification is one of the numerous barriers in proper diagnosis and effective translation of experimental treatments in animal models. TBI is associated with numerous disorders, including amnesia, Parkinson's Disease, sleep disorders, Alzheimer's Disease, as well as disruption of physical, cognitive, and mental functioning. Several health care providers and the insurance industry see TBI as a singular 'event', meaning that the brain ''repairs'' over time, and does not require additional therapies. However, a single mild TBI can induce problems that self-propagate for months or years after the injury. There currently exist no diagnostic methods to quantify the extent of emotional and behavioral changes, cognitive impairment, fatigue, and sleep issues resulting from TBI in affected individual. The various animal and injury models available for TBI research are limited in clinical trials because a single TBI event is not fully understood. This review highlights the classifications of TBI, its heterogeneity, neuropathological lesions, long term sequelae, association with neurodegenerative disorders in human and animal studies, and attempts to modify the notion of TBI being viewed as a singular event. : The significance and strength of this review article lies in its comprehensive exploration of Traumatic Brain Injury (TBI) by addressing various factors that contribute to its complexity. We carried out a careful and detailed review of TBI classifications with an aim to provide a clearer and more detailed understanding of the heterogeneity inherent in these injuries. The examination of neuropathological lesions associated with TBI offers critical insights into the intricate nature of brain damage, fostering a deeper comprehension of the diverse outcomes resulting from TBI. Furthermore, this review critically evaluates the long-term sequelae of TBI, shedding light on the often-overlooked extended consequences that impact individuals well beyond the initial injury period. The findings from human and animal studies not only enriches our understanding of TBI but also highlights the translational implications for both clinical and preclinical research. A pivotal aspect of our review involves investigating the association between TBI and neurodegenerative disorders. By combining information from human studies and animal models, we aim to contribute to the growing body of knowledge that elucidates the intricate links between TBI and the development of neurodegenerative conditions. Most notably, this review challenges the conventional notion of TBI as a singular event by incorporating perspectives that emphasize its multifaceted nature. We critically assess attempts to modify this prevailing paradigm, encouraging a more nuanced understanding that considers the diverse manifestations and outcomes associated with TBI. In essence, this review endeavours to serve as a valuable resource for researchers, clinicians, and policymakers, fostering a comprehensive understanding of TBI that transcends traditional classifications and contributes to a more holistic approach in both research and clinical practice.