Neuropsychiatric Aspects of Traumatic Brain Injury

Over the past decade, concussion has become the most widely discussed injury in contact sports. However, concussions also occur in several other settings, such as non-contact sports, elderly individuals, young children, military personnel, and victims of domestic violence. Concussion is frequently undiagnosed as a cause of psychiatric morbidity, especially when the patient has no history of loss of consciousness or direct head trauma. Almost all of the extant literature focuses on traumatic brain injury and assumes that concussion is merely a mild form of traumatic brain injury, which has resulted in a lack of understanding about what concussion is, and how to diagnose, monitor, and treat its varied neuropsychiatric symptoms...

IMPORTANCE: The late effects of traumatic brain injury (TBI) are of great interest, but studies characterizing these effects are limited. OBJECTIVE: To determine whether TBI with loss of consciousness (LOC) is associated with an increased risk for clinical and neuropathologic findings of Alzheimer disease (AD), Parkinson disease (PD), and other dementias. DESIGN, SETTING, AND PARTICIPANTS: This study analyzed data from the Religious Orders Study (ROS), Memory and Aging Project (MAP), and Adult Changes in Thought study (ACT)...

Cognitive problems are one of the main causes of ongoing disability after traumatic brain injury. The heterogeneity of the injuries sustained and the variability of the resulting cognitive deficits makes treating these problems difficult. Identifying the underlying pathology allows a targeted treatment approach aimed at cognitive enhancement. For example, damage to neuromodulatory neurotransmitter systems is common after traumatic brain injury and is an important cause of cognitive impairment. Here, we discuss the evidence implicating disruption of the catecholamines (dopamine and noradrenaline) and review the efficacy of catecholaminergic drugs in treating post-traumatic brain injury cognitive impairments...

The acute and long-term consequences of traumatic brain injury (TBI) have received increased attention in recent years. In this Review, we discuss the neuropathology and neural mechanisms associated with TBI, drawing on findings from sports-induced TBI in athletes, in whom acute TBI damages axons and elicits both regenerative and degenerative tissue responses in the brain and in whom repeated concussions may initiate a long-term neurodegenerative process called dementia pugilistica or chronic traumatic encephalopathy (CTE)...

Because it is the product of glycolysis and main substrate for mitochondrial respiration, lactate is the central metabolic intermediate in cerebral energy substrate delivery. Our recent studies on healthy controls and patients following traumatic brain injury (TBI) using [6,6-(2)H2]glucose and [3-(13)C]lactate, along with cerebral blood flow (CBF) and arterial-venous (jugular bulb) difference measurements for oxygen, metabolite levels, isotopic enrichments and (13)CO2 show a massive and previously unrecognized mobilization of lactate from corporeal (muscle, skin, and other) glycogen reserves in TBI patients who were studied 5...

Traumatic brain injury (TBI) is a leading cause of mortality and morbidity both in civilian life and on the battlefield worldwide. Survivors of TBI frequently experience long-term disabling changes in cognition, sensorimotor function and personality. Over the past three decades, animal models have been developed to replicate the various aspects of human TBI, to better understand the underlying pathophysiology and to explore potential treatments. Nevertheless, promising neuroprotective drugs that were identified as being effective in animal TBI models have all failed in Phase II or Phase III clinical trials...