Flexible effects of quantified cigarette-smoke delivery on EEG dimensional complexity.
A quantified smoke delivery system (QSDS) was used to experimentally control the administration of inhaled cigarette smoke to 28 male smokers. One puff (2 s, 35 cc) was taken every 30 s on a cigarette (nicotine yield 1.0 mg) until the char line reached 3 mm from the filter wrap. The smoke was inhaled for 5 s. Resting eyes-closed and eyes-open EEG was recorded from F3, F4, P3, and P4 before and after quantified smoke delivery (QSD). EEG dimensional complexity (DCx, a measure derived from chaos theory) was computed using the Takens-Ellner method. QSD appeared to have a 'flexible' effect on EEG DCx, primarily lowering it in subjects whose pre-smoking level was high, not affecting it in subjects whose pre-smoking level was intermediate, and tending to raise it in subjects whose pre-smoking level was low. This replicates previous results obtained with ad libitum smoking, suggesting the hypothesis that smoking may have an "optimizing" effect on the complexity of brain dynamics.
Pritchard
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WS
Biological Research Group R&D, Bowman Gray Technical Center 611-12, R.J. Reynolds Tobacco Company, Winston-Salem, NC 27102.
Gilbert
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DG
Duke
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DW
D000328:Adult; D003367:Cotinine / Q000097:blood; D004569:Electroencephalography / Q000187:drug effects*; D006801:Humans; D008297:Male; D009538:Nicotine / Q000097:blood; D017711:Nonlinear Dynamics; D009799:Ocular Physiological Phenomena; D012907:Smoking / Q000097:blood / Q000503:physiopathology*
D009538:Nicotine; D003367:Cotinine