Biomedical subjects

M Hasenfratz

Publications and source records attributed to M Hasenfratz.

21 records · Page 2Linked to original sources

PubMed1989

Can smoking increase attention in rapid information processing during noise? Electrocortical, physiological and behavioral effects.

This study investigated the effects of smoking on subject-paced visual rapid information processing performance (RIP) under the influence of disturbing noise. The RIP task required the subjects to detect triads of even or odd digits within a pseudorandom sequence of single digits presented on a screen. Two groups of 12 female habitual smokers who were not allowed to smoke during the last 10 h preceding the test sessions underwent two test sessions each consisting of two RIP trials separated by a smoking period (habitual cigarette) for one group and by a relaxation period without smoking for the second group. Noise disturbance was presented during the second RIP trial of one of the two sessions only. Smoking increased RIP performance, but noise failed to show any measurable effect. EEG analyzed during RIP revealed the expected noise-induced decrease in alpha power. ERP analyses showed a smoking-induced decrease in the CNV-related negativity but no noise effects. The late positive wave (LP) increased after smoking, but to a lesser extent under the noise condition. The analyses of peripheral physiological measures revealed smoking- and noise-induced heart rate acceleration and cutaneous vasoconstriction. Plasma cortisol, prolactin and HGH were also increased after the noise session. The results indicate therefore that smoking increased RIP, whereas noise failed to affect mental performance, although it produced measurable vegetative stress effects.

Adult↗

PubMed1989

Postlunch smoking for pleasure seeking or arousal maintenance?

Interactions between smoking and eating might be expected, since the craving to smoke increases after a meal, since smokers tend to have a lower body weight and since they have also been suggested to differ from nonsmokers with respect to metabolism. Further, both eating and smoking have been reported to affect mental performance. In the first experiment the influences of a heavy meal, a light meal and no meal on smoking behavior and subjective ratings were compared in 15 subjects. Whereas puffing behavior was not affected by the meal conditions, craving and smoking enjoyment increased after the meals. In the second experiment the effects of smoking on postlunch performance and concomitant central and peripheral physiology were investigated. Postlunch smoking (compared to postlunch no smoking) distinctly showed the usual increases in heart rate, peripheral vasoconstriction and electrocortical arousal, but it failed to affect rapid information processing performance and its concomitant event-related EEG potentials as well as several indices of metabolic activity. It appears, thus, that under the conditions of the present experiments, pleasure seeking may be a more important factor in postmeal smoking than the effects on performance, EEG or metabolism.

Adult↗

PubMed1988

Cardiovascular, electrocortical, and behavioral effects of nicotine chewing gum.

The cardiovascular, electrocortical, and behavioral effects of orally administered nicotine during rapid information processing were assessed in deprived female smokers. In a pre-post treatment design, 10 subjects received a 4-mg nicotine chewing gum and 10 subjects a placebo. The mental task required the subjects to watch single digits presented in a pseudorandom order on a screen and to press a button whenever the last three digits were either odd or even. The presentation rate decreased after each error and increased after each correct response and was used as the index of performance. Event-related brain potentials (ERP) to each of the three digits of the correctly answered triads were analyzed. The ERPs showed a distinct CNV potential for the second digit only (expectancy) and a P300 response for the third digit only (response decision). The mean EEG power spectrum was computed for each 5-min resting period, set before each trial and at the end of the session. A single administration of 4-mg nicotine chewing gum was followed by heart rate increase, acrodermal vasoconstriction, increase in theta and alpha frequency, decrease in delta power, and increase in the CNV magnitude. However, the chewing gum neither increased performance or reaction time nor decreased any ERP latencies or amplitudes, as has been reported after cigarette smoking.

Adolescent↗