In neurology, abulia, or aboulia (from , meaning "will"), refers to a lack of volition, will, or initiative and can be seen as a disorder of diminished motivation. Abulia falls in the middle of the spectrum of diminished motivation, with apathy being less extreme and akinetic mutism being more extreme than abulia. The condition was originally considered to be a disorder of the will, and aboulic individuals are unable to act or make decisions independently; and their condition may range in severity from subtle to overwhelming. In the case of akinetic mutism, many patients describe that as soon as they "will" or attempt a movement, a "counter-will" or "resistance" rises up to meet them.
Symptoms and signs
The clinical condition denoted abulia was first described in 1838; however, since that time, a number of different, some contradictory, definitions have emerged. Abulia has been described as a loss of drive, expression, behavior and speech output, with slowing and prolonged speech latency, and reduction of spontaneous thought content and initiative, being considered more recently as 'a reduction in action emotion and cognition'. Patients may continue to chew or hold food in their mouths for hours without swallowing it.
Damage to the basal ganglia
Injuries to the frontal lobe and/or the basal ganglia can interfere with an individual's ability to initiate speech, movement, and social interaction. Studies have shown that 5-67% of all patients with traumatic brain injuries and 13% of patients with lesions on their basal ganglia experience some form of diminished motivation.
Damage to anterior cingulate circuit
The anterior cingulate circuit consists of the anterior cingulate cortex, also referred to as Brodmann area 24, and its projections to the ventral striatum which includes the ventromedial caudate. The loop continues to connect to the ventral pallidum, which connects to the ventral anterior nucleus of the thalamus. This circuit is essential for the initiation of behavior, motivation and goal orientation, which are the very things missing from a patient with a disorder of diminished motivation. Unilateral injury or injury along any point in the circuit leads to abulia regardless of the side of the injury, but if there is bilateral damage, the patient will exhibit a more extreme case of diminished motivation, akinetic mutism.
Diagnosis
Diagnosis for abulia can be quite difficult because it falls between two other disorders of diminished motivation, and one could easily see an extreme case of abulia as akinetic mutism or a lesser case of abulia as apathy and therefore, not treat the patient appropriately. If it were to be confused with apathy, it might lead to attempts to involve the patient with physical rehabilitation or other interventions where a source of strong motivation would be necessary to succeed but would still be absent. The best way to diagnose abulia is through clinical observation of the patient as well as questioning of close relatives and loved ones to give the doctor a frame of reference with which they can compare the patient's new behavior to see if there is in fact a case of diminished motivation.