With this study, the investigators aim to test whether acute administration of selective serotonin reuptake inhibitors (SSRI) improves motor performance in a sequential motor learning task in comparison to placebo in healthy humans.

Microdialysis findings in animal models provide evidence for a monoaminergic augmentation of motor function. However, this evidence is largely limited to noradrenaline and dopamine, with little evidence to support a similar effect for serotonin. What remains to be tested therefore, is whether acute serotonergic administration induces neural or behavioral changes during motor learning also. Using a sample of 60 female participants (with the possible inclusion of male participants at a later date), the investigators aim to test the effects of a serotonergic challenge on motor learning and plasticity in healthy participants.

Inclusion Criteria:

• female
• right-handed
• healthy
• has taken oral contraceptives (ovulation inhibitor) continuously for at least 3 months
• has read and agreed to study parameters

Exclusion Criteria:

• tattoos on head or neck
• non-removable metal on or in body
• alcohol abuse
• is currently taking medication
• smokes more than 3 cigarettes per day
• positive drug test
• pregnancy
• plays an instrument professionally
• plays videogames more than 2 hours per week
• is a professional athlete
• suffers from migraines
• has taken part in another study, where motor learning skills and/or medication is a factor, in the last 3 months
• heart rhythm disorders (long QT)
• hypertension
• calcium or magnesium deficiency
• neurological disorders
• chronic metabolic disorders
• liver or kidney diseases
• immunodeficiency
• endocrine disorders
• psychiatric disorders
• tumors
• injuries to the head and brain

Double-blind