Double-dummy design of study drug administration. The 2 middle columns display the content of the 2 capsules ingested before the testing session.
| Content of capsules | |||
|---|---|---|---|
| Administered substance | t0 | t1 (1.5 h after t0) | t2 (2.5 h after t0) |
| Haloperidol | Haloperidol | Placebo | Onset of testing session |
| L-dopa | Placebo | L-dopa | Onset of testing session |
| Placebo | Placebo | Placebo | Onset of testing session |