Responsible use of psychostimulants

Psychostimulants have a place in the therapy of attentional disorders. However, they are also widely used off-label to enhance cognitive performance, and their mechanisms of action remain elusive. Westbrook et al. studied the effects of these drugs and concurrently measured striatal dopamine synthesis capacity in young, healthy participants (see the Perspective by Janes). They administered a placebo, methylphenidate (a dopamine and noradrenaline reuptake blocker), and sulpiride (a selective D2 receptor antagonist) while participants made explicit cost-benefit decisions about whether to engage in cognitive effort. Higher dopamine synthesis capacity in the caudate nucleus was associated with greater willingness to allocate cognitive effort. In addition, methylphenidate and sulpiride increased subjective values and motivation to work specifically for people with low dopamine synthesis capacity. Cognition-enhancing drugs may thus act at the motivational level rather than directly boosting cognition per se.

Science, this issue p. 1362; see also p. 1300