Abstract
Eight healthy paid male volunteers (age: 21–28 years, mean: 24.5 ± 1.7 years; weight 62–79 kg) were administered via intravenous infusion (3 min) acute 25-, 50-, and 75-mg doses of phosphatidylserine, or matching placebo in a latin-square design. Multichannel EEG recordings were performed in baseline conditions, during intravenous infusion, and 10, 30, 90, 180, and 360 min after drug/placebo administration. Blood pressure, heart rate, critical flicker-fusion frequency, and the subjects’ performance at immediate and short-term retention tests were assessed after each electroencephalographic (EEG) recording. The EEG signal was quantified offline by power spectral analysis, and bidimensional scalp maps were produced for each EEG variable. Descriptive statistical comparisons among subjects and between pre- and postdrug EEG recordings allowed the detection of systematic EEG changes (notably increment of the power on the ‘alpha’ frequency, which was restricted to the anterior electrode derivations at the 50-mg dose and widespread to the whole scalp at the highest dose, and increase of the signal total power) in the absence of significant modifications of the subjects’ neuropsychological status.