Fig. 2.

Time trends of the absolute band powers of EEG fromt the frontal cortex (FC). All doses of physostigmine (Phy: 0.2, 0.5 and 1 mg/kg, i.p.) produced decreases of all other band powers but GA band power which was increased. In contrast, significant changes were observed differently by some doses of yohimbine (Yoh: 1, 2 and 5 mg/kg, i.p.) according to the bands. ^*p<0.05, significantly different from the Pre. DE: delta, TH: theta, AL: alpha, BE: beta, GA: gamma, and TO: total power, Pre: a period of 11:00~12:00, S1 to S8: the first to 8^th segments (every 15 min period after a dose).