Effects of Nicotine Upon Cortical and Subcortical Electrical Activity of the Rabbit Brain: Quantitative Analysis

Acute effect of nicotine on auditory gating in smokers and non-smokers

“…Similar findings have been reported for cigarette smokers (Friedman et al, 1974;Friedman and Meares, 1980;Knott, 1985aKnott, ,b, 1986 as well as patients suffering from schizophrenia (e.g., Adler et al, 1993) and dementia Jones et al, 1992;Newhouse et al, 1992). They are also consistent with the results of numerous studies on different species of animals including rats (Bhargava et al, 1978;Curzon et al, 1994;Stevens et al, 1995;Ehlers et al, 1997), cats (Schaeppi, 1967;Armitage et al, 1969), and rabbits (Goldstein et al, 1967;Longo et al, 1967). That these results represent a central, rather than peripheral, effect of nicotine is supported by the fact that (i) transdermal administration of nicotine has no effect on otoacoustic emissions measured from human ears (Harkrider et al, 2001), and (ii) direct application of nicotine has no effect on the measured responses of isolated cochlear outer hair cells (Erostegui et al, 1994;Fuchs and Morrow, 1992;Housley and Ashmore, 1991).…”

“…These receptors also can be excited by nicotine, which mimics the actions of ACh, and so is known as an acetylcholinomimetic drug. Studies in rats (Bhargava et al, 1978;Curzon et al, 1994;Stevens et al, 1995;Ehlers et al, 1997), cats (Schaeppi, 1967;Armitage et al, 1969), and rabbits (Goldstein et al, 1967;Longo et al, 1967) have shown that nicotine receptors excite ascending pathways to the cortex. Consistent with this, human behavioral and electrophysiological studies of heavy smokers (e.g., Friedman et al, 1974;Friedman and Meares, 1980;Knott, 1985aKnott, ,b, 1986 indicate that smoking-induced changes are concurrent with more efficient information processing, including decreased response times to stimulus detection, improved stimulus discrimination, and increased sustained attention to sensory stimuli.…”

Paradoxical tranquilizing and emotion-reducing effects of nicotine.

“…The EEG arousal occurs immediately after the intravenous administration of nicotine and by the time the individual completes smoking a tobacco cigarette. Several studies using subhuman mammals have reported this initial phase of EEG arousal to be followed by a phase of EEG tranquilization that occurs about 5-15 minutes after the intravenous administration of the drug and lasts up to 30 minutes (Bhattacharya & Goldstein, 1970;Domino, 1967;Goldstein, Beck, & Mundschenk, 1967). However, no such secondary phase of EEG tranquilization has been shown to occur in humans.…”

“…Another model has been suggested by Goldstein et al (1967). It is based on their studies of the effects of nicotine on simultaneous quantitative measures of cortical electrical activity in the rabbit brain.…”