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Abstract:
Abstract: Smoking may improve information processing speed
and inhibitory processing (Bates et al., 1994) possibly due to the
functional role of the cholinergic system in maintaining a state
$E3appropriate for efficient information processing$E4 (Pineda et
al., 1998). Thus, tobacco substances may serve a neurotherapeutic
role by improving sensory gating and attentional processes. Prior
evidence (Adler et al., 1993) suggests this to be the case for
schizophrenics. We investigated whether there are sensory gating
differences between healthy 20-40 year old smokers and nonsmokers.
Thirteen heavy smoking (20+ cigarettes per day; 5+ years smoking)
and 13 nonsmoking healthy men were compared during a P50 auditory
event-related paradigm (50 pairs [prepulse followed by target tone]
of 70 dB tones, .512 sec between paired tones, 5 sec SOA between
tone pairs). Auditory event-related potentials were recorded at 29
sites. Smokers were evaluated under conditions of abstaining
overnight vs smoking, while nonsmokers were tested twice without
smoking. Regardless of condition, in comparison to nonsmokers,
smokers showed (a) higher P50 amplitudes to prepulse and target
tones, and (b) greater prepulse inhibition than nonsmokers. Smoking
had enhancing effects on prepulse inhibition in some but not other
brain regions. For example, at both Cz and Fz, smokers showed
greater prepulse inhibition than nonsmokers, yet significant
tobacco effects were seen at Cz but not Fz for smokers. Although
addictive, tobacco may improve sensory and cognitive processing in
some individuals.
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