Forty-two patients with probable Alzheimer's disease (AD) and 18 elderly healthy controls underwent quantitative EEG (qEEG) and regional cerebral blood flow (rCBF; 133Xe clearance) examinations. Correlations were sought between relative qEEG band powers and percent rCBF values in a posterior temporoparietal region of interest in either hemisphere. Moreover, stepwise discriminant analysis was applied to study the accuracy of the two techniques in differentiating AD from healthy ageing. rCBF and qEEG were correlated with one another, especially in the right hemisphere (p values ranging from <0.001 to <0.01). Significant correlations were found between Mini Mental State Examination (MMSE) and relative power of both the 2- to 6-Hz and the 6.5- to 12-Hz bands on either side (p < 0.001), and between MMSE and left rCBF (p < 0.005), while the correlation with right rCBF was poorer (p < 0.02). The statistical procedure identified the right values of both examinations for the discriminant analysis. Sensitivity of qEEG and rCBF employed together was 88% and specificity 89%, with a total accuracy of 88.3%. The unrecognized patients (n = 5) were affected by mild AD (4 scoring 3 at the Global Deterioration Scale and 1 scoring 4). qEEG alone showed an accuracy of 77% in the whole group and of 69% in mild AD, and rCBF alone an accuracy of 75% in the whole group and of 71% in mild AD. It is concluded that qEEG and rCBF examinations employed together are accurate tools to differentiate AD from normal ageing, although a lower degree of accuracy is achieved in mildly demented patients.

Aged↗

PubMedDate not supplied

Phosphatidylserine: quantitative EEG effects in healthy volunteers.

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 off-line 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 deviations at the 50-mg dose and the 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.

Adult↗

PubMedDate not supplied

Quantitative EEG effects and drug plasma concentration of phenobarbital, 50 and 100 mg single-dose oral administration to healthy volunteers: evidence of early CNS bioavailability.

Single, 50- and 100-mg oral doses of phenobarbital and a matching placebo were administered double-blind to 8 young, healthy male subjects. Multilead electroencephalographic (EEG) samples were recorded prior to, and at regular intervals within the 2 h following administration. The EEG signal was processed by power spectral analysis; the drug plasma concentration was assessed concomitantly. Plasma peaks after the 50- and 100-mg dose were, respectively, 3.38 +/- 1.29 and 4.09 +/- 1.24 micrograms/ml. Despite the low drug plasma concentration, a systematic power increment of the EEG fast frequency spectral segments occurred at either dose on the anterior scalp areas from the 30- or 60-min postdrug control onward, and was preponderant on central electrodes; a significant correlation (Kendal's coefficient for ranked data) with the drug plasma concentration was observed limitedly to the anterior scalp areas. No correlation with plasma levels was observed for unsystematic EEG variations.

Administration, Oral↗