A Comparison between the Rhesus Monkey and the Human on the Effect of Atropine on the Electroencephalogram. Volume 2. Preliminary Statistical Analysis of Spectral EEG Waveforms in Rhesus Monkeys Exposed to Atropine

Statistical models were developed to analyze the effects of atropine on brain activity. Brain activity was measured from the spectral EEG waveforms as a function of the percent power in the first five frequency bands. The statistical analyses indicated that: (1) High and medium doses of atropine were associated with a statistically significant increase in percent power in the first frequency band, with an decrease in percent power in the fifth frequency band, which persisted through the 600 minute time point. (2) The low atropine dose was associated with a statistically significant increase in percent power in the first frequency band, and a decrease in percent power in the fifth frequency band, at the 30 and 90 minute time points. Following the low atropine dose, there were no significant measurable effects of atropine on EEG waveforms at the 300 and 600 minute time points. (3) There were no significant measurable trends in the EEG waveforms for monkeys injected with the saline control. (4) The effect of atropine on brain activity (as measured by EEG) appears to diminish with respect to time since dosing.