Brain damage is the term used to refer to injury- or disease-related damage to the physical structure of the brain. It can be caused by various means, such as physical trauma (e.g. as in a blow to the head, or a stroke), or by an underlying neurological condition. Damage caused to the brain may result in physical, cognitive and/or perceptual impairments, each of which can vary from mild to severe. The effects of brain damage are wide-ranging and can include behavioural deficits, reduced mobility and problems with sensory input and output. Consequently, the impact of brain damage can be profound and life-changing for those affected.

See also: right hemisphere, left hemisphere, corpus callosum, split brain