There’s more to apathy than sheer laziness

Researchers at the UCL Institute of Cognitive Neuroscience may have found a biological mechanism that could explain apathy, or lack of motivation.

As Dr Jen Middleton reports, the findings open the possibility for treating the condition with existing medications.

We’ve all had that feeling, usually on a Friday afternoon, when you’ve got a heap of emails to get through but you just can’t be bothered. For some people though, that lack of motivation or apathy is much more serious and can have severe consequences on their lives, particularly for patients with Alzheimer’s and Parkinson’s.

Apathy is distinct from depression, yet despite increasing awareness of the syndrome we lack a good biological model to study it, and there is no treatment for the condition.

The team studied a patient experiencing profound apathy following a stroke which damaged a particular area in his brain. Prior to the stroke, he was an exuberant and outgoing character but the stroke transformed him into a reticent and reserved individual, unmotivated even to maintain personal hygiene.

The stroke affected a particular region of his brain, the basal ganglia, that is known to be important for value-based decision making and modulating behaviour in response to reward.

Professor Masud Husain, a Wellcome Trust Principal Research Fellow who led the study, explains: “Apathy is difficult to study in patients with neurodegenerative diseases as there are so many areas of the brain affected that it is difficult to interpret the results. This patient gave us a rare opportunity to investigate whether this area of the brain, and reward sensitivity in particular, plays a role in apathy.”

The patient was given experimental tasks to perform to assess his decision-making processes in response to rewards. Throughout the tests he showed little interest in taking risks for rewards, even when given the opportunity to maximise the overall reward he could obtain.

The brain chemical dopamine, often described as the ‘feel-good’ factor, is known to be important for effort-based decision making. When the team treated the patient with a precursor to dopamine  that is converted to dopamine in the brain, he showed a partial increase in reward sensitivity. However, a drug that mimics the effects of dopamine on the receptors in the brain had a much more profound effect, with the patient becoming much more motivated to take risks during the experiment. At the same time, outside of the study, he began to go out more, found a job and became more sociable.

Professor Husain adds: “It took about three months to see the effects but they really were quite profound. The treatment literally transformed the patient’s life.

“Many patients with apathy are wrongly labelled as just being lazy. Although this is just one patient, these findings are important because they highlight a biological explanation for lack of motivation, and importantly that this can be treated with drugs.”

The team are now planning to investigate the effects of the drug treatment on patients with Alzheimer’s and Parkinson’s Disease who are experiencing apathy.

Jen is a Media Officer at the Wellcome Trust.

Reference:

Adam R, Leff A, Sinha N, Turner C, Bays P, Draganski B, & Husain M (2012). Dopamine reverses reward insensitivity in apathy following globus pallidus lesions. Cortex PMID: 22721958

Image credit: Stephen Magrath, Wellcome Images