Aggression in Brain Injury, Aging, and Neurodegenerative Disorders

Abstract

Among the most prominent and devastating neurological disorders are those that involve degeneration of neurons as the result of acute injuries (traumatic brain injury and stroke) or age-related diseases including Alzheimer’s disease (AD), Parkinson’s disease (PD), and Huntington’s disease (HD). Not only are these disorders major causes of death, but each typically involves long-term morbidity that exacts great tolls on relatives and healthcare systems. These disorders manifest degeneration of nerve cells in particular brain regions, resulting in deficits in the functions controlled by those brain regions: learning and memory in AD, body movements in PD and HD, and speech and language in many cases of stroke and head trauma (Table 1). The purpose of this chapter is to provide a brief overview of the pathogenesis of acute and chronic neurodegenerative conditions that manifest aberrant aggressive behaviors and to consider the neurobiological substrates of aggression in each disorder.