Apathy is a common effect of traumatic brain injury, but one that is not well understood. Apathy has traditionally been defined as emotional indifference, but the reality of apathy is far more complex. For people who have suffered from a traumatic brain injury, apathy is better illustrated as diminished goal-directed behavior. Goal-directed behavior is defined as a set of processes, including motivation, emotion, cognition, and motor skills that are initiated into action in order to reach a goal. The "direction" part of goal-directed behavior comes from the understanding of the relationship between the action and an outcome. Apathy is therefore not as simple as a lack of motivation or emotion. It is a much more complex syndrome that is related to injury to specific parts of the brain.
Injury to the dorsolateral prefrontal cortex, orbitofrontal cortex, insula, and white matter tracts can be linked to apathy. A diagnosis of apathy can be made when a person displays (in absence of a change in consciousness) diminished motivation in relation to previous behavior, and four weeks of at least two of the following: 1) diminished goal-directed behavior, 2) diminished goal-directed cognitive activity, and 3) diminished emotions.
Apathy after a traumatic brain injury is a major source of disability, accounting for serious consequences not only for the patient, but also the family and caregivers. Successful rehabilitation after a traumatic brain injury frequently depends on the level of initiation and motivation of the patient to strive towards goals. Without the ability to understand or initiate goal-directed behavior, the rehabilitation of other lost cognitive or motor functions can be a significant challenge.
As apathy can be understood as a complex syndrome that spans cognitive, emotional, motivational, behavioral, and social roles, it is important for caregivers and rehabilitation professionals to treat apathy within each of these roles. A multidimensional, integrative approach to treating apathy may have much more success than treating apathy as a simple motivational or emotional disorder.
Arnould A, Rochat L, Azouvi P, & Linden M. A multidimensional approach to apathy after traumatic brain injury. Neuropsychology Review. (September 2013).