Perspectives on Classification of Brain Injuries
Dan Lewis Foundation | Spring 2023

The medical care and medical research fields have traditionally classified brain injuries as either Acquired Brain Injuries (ABIs) or Traumatic Brain Injuries (TBIs). From a broad perspective, all brain injuries are “acquired,” except congenital disorders. But the terms ABI and TBI have each, over time, taken on specific definitions with different implications, which are discussed here.


The term ABI is usually applied to injuries caused by a wide range of factors including strokes, infections, tumors, anoxia (lack of oxygen to the brain, for instance, from drowning or choking), neurotoxic poisoning, drug overdose, aneurysms, seizures, electric shock, and other factors. 


The term TBI is applied to injuries caused by an external force or physical blow to the head. Major TBI causes include falls, assaults, motor vehicle accidents, gunshot wounds, child abuse, domestic violence, military actions (blast injuries), and workplace injuries. Injuries to the brain caused by rapid extreme acceleration and deceleration of the brain within the skull (as can occur in cyclist vs. motor vehicle events or “shaken baby syndrome”) are also Perspectives on Classification of Brain Injuries considered TBIs.


The use of these classifications can be helpful to healthcare professionals in understanding the causes of an individual’s brain injury and in considering which diagnostic tests and treatments will likely be most beneficial. In research settings, the use of the terms ABI and TBI may facilitate better-designed protocols and lead to more reliable and interpretable findings regarding causes, risk factors, and treatments. Further, the lay public may benefit from understanding the different signs and symptoms that indicate an ABI versus a TBI and may gain a better appreciation of the importance of seeking timely medical attention when these signs appear.


The use of the terms ABI and TBI have received criticism as well. Categorizations, broad as the terms ABI and TBI are, can lead to overgeneralizing the symptoms and outcomes of brain injuries. The unique nature of the brain injury that any individual suffers and the evolving nature of the short-term and long-term consequences of that injury should not be obscured by a label. Additionally, a degree of stigmatization can occur by applying these labels. This can also be the case when brain injury severity labels—mild, moderate, severe-are used early in the course of an individual’s brain injury and endure for a long time despite changes in the individual’s status. Further, some studies have shown inequities in access to services, supports, and resources across different brain injury categories. More specifically, funding for services and resources, particularly government funding, is sometimes more favorable for those diagnosed with TBI than those diagnosed with ABI.


The DLF recognizes that the use of the terms ABI and TBI has different implications in different contexts. This is true for the brain injury severity ratings (“mild,” “moderate,” and “severe”) as well. The idea that these labels may be more or less beneficial depending on context and the constituency group being addressed appears to be consistent with the stance taken by the Brain Injury Association of America. The DLF supports using the more general and simpler term “brain injury” in the context of dissemination of information, referral to resources, and advocating for individuals with brain injury and their families. However, as an organization that aspires to catalyze basic research into biomolecular medicines, technological advances, and other biomedical innovations that promote regeneration of the damaged brain, we recognize that classification and clear specification of research protocols are necessary for building a reliable and progressive knowledge base.

By Dan Lewis Foundation | Spring 2024 11 Apr, 2024
Graham Dempsey, Ph.D., is a founder and Chief Scientific Officer (CSO) at Quiver Bioscience, a Cambridge, Massachusetts-based biotechnology company focused on the development of medicines for disorders of the nervous system. Dr. Dempsey and his team are working to develop treatments for some of the most challenging unsolved medical issues patients and their families face. Using advanced technologies in human stem cell biology, optogenetics, machine learning, and drug screening, progress is being made to develop medicines that will one-day treat conditions that have been largely untreatable. As the lead scientist for Quiver, formerly Q-State Biosciences, Dr. Dempsey enjoys working with world-class teams to invent, develop, and apply cutting-edge technologies to solve the most difficult challenges in biopharma for the betterment of patients. Dr. Dempsey’s inspiration to dedicate his professional life to science and medicine started at the early age of seven with the tragic loss of his father to an aggressive form of cancer, an experience that has deeply motivated him to this day. He completed his undergraduate studies at the University of Pennsylvania and his doctorate at Harvard University. As a graduate student in the biophysics program at Harvard Medical School, he co-developed ‘Stochastic Optical Reconstruction Microscopy’ or STORM , a light microscope with the ability to resolve nanometer (billionth of a meter, e.g. a hair is 100,000 nanometers thick) scale details of biological materials, an achievement that had been thought to be impossible for over a century. STORM has enabled what researchers call ‘super-resolution imaging’ for visualizing the intricate details of life’s most fundamental unit, the cell. Understanding the inner workings of a cell provides a path to a deeper understanding of the ways in which life is constructed and diseases can manifest. The technology was commercialized by Nikon Instruments for researchers worldwide. Dr. Dempsey left academic science to join Q-State Biosciences as the first hired employee with the goal of bringing advanced technologies developed at Harvard to the study of the brain. The brain, arguably the most complex structure in the known universe, works through electrical communication between brain cells or neurons. This communication is disrupted in all brain disorders but has been near impossible to study for the purposes of effectively developing medicines. Dr. Dempsey and his team over the course of ten years built a technology system that creates human brain models from patient stem cells (i.e. a ‘disease-in-a-dish’) and converts electrical activity of those brain cells into light signals that can be detected with ultra-sensitive microscopes. The resulting signals are analyzed using machine learning to find the patterns of how electrical activity is altered in disease, which can be used to find medicines that correct those changes. The team at Quiver is deploying this technology to take on previously untreatable brain conditions, including rare genetic diseases, such as certain seizure and neurodevelopmental disorders, to common conditions, such as chronic pain and Alzheimer’s disease. Dr. Dempsey’s passion outside of science starts with his family, his wife (and high school sweetheart) and three young daughters, be it traveling the globe to experience new cultures (or simply stare at the ocean), cooking elaborate meals on a Saturday evening, night-time reading of novels to his daughters, or attending live music around Boston. As a native of NJ, he celebrates his roots with visits to family near the Jersey Shore and, whenever possible, attendance at Springsteen concerts and Giants games. Dr. Dempsey is an avid student of history’s great entrepreneurs, spending the sparse remaining minutes of the day reading biographies and listening to podcasts, looking to extract every bit of learning towards taking on the challenges of building a great business while staying true to his family, his Quiver teammates, and his professional mission.
By Dan Lewis Foundation | Spring 2024 11 Apr, 2024
Sheryl Suzanne Nibbs, a legal secretary in a top law firm, started the process of becoming a paralegal as she approached her 40th birthday. She was fancy in her appearance, always making sure her hair, nails, and clothing were in order, a well-kept person, an avid traveler, and her mother’s best friend.
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