Conclusions:
PVT
The present study demonstrates that 200 mg modafinil and 300 mg caffeine
significantly decrease the effects of a limited period of sleep deprivation
on vigilance compared with placebo. Although PVT parameters already improved
2 h after administration, the most notable effects occurred 2–4 h later.
Modafinil seems to be effective longer than caffeine, which is consistent
with its longer half-life.