Rico Nil

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 taks 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.

Nicotine yield as determinant of smoke exposure indicators and puffing behavior

Relationships between machine smoking nicotine yield and different smoke exposure indicators were investigated in a cross-sectional study. For each of the four yield classes H (1.0-1.2 mg), M (0.7-0.9 mg), L (0.4-0.6 mg) and U (0.1-0.3 mg) 18 male and 18 female subjects were recruited. The experimental design (2 x 2) included smoking with lip contact or with a flowmeter holder, natural smoking of one cigarette or forced smoking (30 puffs). The analysis of presmoking measures revealed for plasma nicotine H greater than L, U; M greater than U, for plasma cotinine H, M greater than U, and no differences for respiratory CO. Pre- to postsmoking boosts of CO and nicotine increased with yield, but the differences were smaller than those in yield. This partial compensation can be attributed to puffing behavior as revealed by the differences between yield classes with respect to flowmeter measures (puff volume, flow parameters, number of puffs). Contact condition hardly influenced the results. Forced puffing revealed down regulation mechanisms in smoke absorption and, less pronounced, in puffing behavior. Cardiovascular and subjective effects were widely independent of yield. Plasma cotinine appeared as the best smoke exposure indicator, due both to its high retest reliability and its relationship to nicotine yield.

Separate effects of cigarette smoke yield and smoke taste on smoking behavior.

The purpose of this experiment was to compare independently the influence of different cigarette smoke taste categories and different machine standard smoke yield values on cigarette smoking behavior and related subjective measures. In six separate sessions 15 regular smokers were presented with a medium and a low smoke yield cigarette of each of the three taste categories, mentholated, dark (Gauloises) and blond (Muratti) tobacco. Each session, included a “natural” and a “forced” smoking procedure of one cigarette type only. Forced smoking consisted of smoking 30 puffs whereby a new half-length cigarette was presented after every third puff. During the seventh session, habitual brand cigarettes were smoked as a reference. The sessions followed in weekly intervals, and the subjects became familiar with the test cigarettes during the last 5 days preceding each test session. Although general acceptability of the cigarettes, smoking satisfaction and pleasantness of taste were clearly lower for all test cigarettes as opposed to the habitual brand reference, cigarettes, these measures remained unaffected by taste or smoke yield of the test cigarettes. Harshness of smoke was higher in the dark tobacco category and generally decreased with the lower smoke yield cigarettes. Independent effects of taste and smoke yield were obtained for total puff volume, inhalation time and CO absorption, suggesting a compensatory intensification of smoking behavior for low yield cigarettes and an independent increase of smoking intensity from mentholated to dark tobacco to blond tobacco. The results suggest therefore that factors which affect cigarette smoke taste have effects on smoking behavior which are separate from those obtained by comparing smoke yields.

Development of central and peripheral smoking effects over time

The present study compared for the first morning cigarettes CO and nicotine absorption as well as the effects on EEG and peripheral functions across a period of 90 min. Eighteen smokers participated in two sessions, one in which they smoked two cigarettes in succession and another in which they smoked three cigarettes at 30-min intervals. Smoking two cigarettes in succession produced a particularly wide range in nicotine absorption so that the subjects could be grouped into high (HN) and low (LN) nicotine absorbers, differing significantly in their CO and nicotine absorption. The smoking-induced cardioacceleration was greater and lasted longer in the HN than in the LN group. While the dominant alpha frequency increased to a significant extent in the HN group only, beta power increased in both groups, alpha power remained unaffected, theta power decreased in the HN group only and the effects on heart rate, dominant alpha frequency and beta power were significantly correlated with nicotine absorption across both groups. Smoking three cigarettes at 30-min intervals produced qualitatively similar but generally smaller effects. However, neither nicotine uptake nor any of the physiological parameters showed differential developments between the two groups, except the dominant alpha frequency, which increased in the HN group only. The development of acute tolerance to smoking across three cigarettes was observed only for finger vasoconstriction, craving to smoke and sickness after smoking, but not for cardioacceleration or any EEG parameters.

Effects of smoking deprivation on smoking behavior and heart rate response in high and low CO absorbing smokers.

Short-term deprivation effects on smoking-induced heart rate response and smoking behavior were compared in consistently high and low CO absorbing smokers, suggested to depend differentially on smoking and/or nicotine. The subjects came to the laboratory for two afternoon sessions and smoked at 1 p.m. and at 5 p.m. both after previous free smoking and following afternoon or overnight-morning deprivation. Overnight-morning deprivation decreased presmoking heart rate in both groups similarly, but it increased heart rate response to smoking more in the high than low CO absorbers. Single cigarette tidal CO boosts concomitantly decreased in the high CO absorbers and remained at the habitually low level among the low CO absorbers. Afternoon deprivation had no effects on presmoking heart rate, presmoking tidal CO concentration and tidal CO boost, but increased the heart rate response to smoking in the high CO absorbers. Smoking need and satisfaction as well as puff volume and duration tended to increase after both deprivations slightly more among the high than low CO absorbers. These results are discussed in terms of a differential development of acute tolerance to nicotine in the two groups of smokers which dissipates during smoking abstinence periods.

Development of puffing behavior along burning time of a cigarette — No relation to alveolar inhalation or nicotine delivery of the cigarettes?

The curves of the cumulative smoke volumes (CSV), as determined by the number of puffs, the puff intervals, the single puff durations, and puff volumes, of 108 nondeprived smokers who smoked two personal brand cigarcttes revealed statistically distinct clusters. Pronounced nonlinear increases in the puff intervals and modest decreases in the puff volumes were seen generally, but they varied in extent between clusters as did the number of puffs and estimated mouth intake of nicotine. Most clusters (representing 80% of the smokers) did not deviate significantly from a linear development of the CSV curves, and those that did were characterized by particularly short puff intervals. Most of the subjects moved from the first to the second cigarette into clusters of similar shapes. However, none of these conclusions showed any relation either to the nicotine yield of the cigarettes or to the pre- to postsmoking Δ tidal CO. It was therefore concluded that the sensory consequences of the physicochemical changes in smoke composition between the first and last puff or other as yet unknown psychological factors are more likely candidates than nicotine satiation for explaining the typical changes in puffing behavior along burning time of a cigarette.

Ultralow-yield cigarettes and type of ventilation: The role of ventilation blocking

Habitual smokers of perforation-ventilated cigarettes and of channel-ventilated cigarettes (18 male and 18 female subjects each; nicotine yield 0.1-0.3 mg, 0.2 mg, respectively) were compared with respect to different smoke exposure indicators and puffing behavior. The role of ventilation blocking was assessed by comparing normal lip contact with smoking through a cigarette holder. The presmoking concentrations (plasma nicotine, cotinine, respiratory CO) were higher for channel-filter than for perforation-ventilated cigarettes, as were the pre- to postsmoking boosts (nicotine, CO) with normal lip smoking. Holder smoking resulted in lower boosts than lip smoking for the channel filter cigarettes, although the puffing behavior was considerably intensified. The boosts for perforation-ventilated cigarettes remained unchanged and were reached with only moderately intensified puffing behavior. The results indicate the importance of ventilation blocking in everyday lip smoking for channel-filter cigarettes, but not for conventional, perforated cigarettes.

Ischemic ECG changes are found more often in asymptomatic men with a coronary prone behaviour pattern

Type A behaviour has been related to coronary heart disease (CHD) as an independent risk factor. Therefore, ischemic electrocardiographic (ECG) changes may be more prominent in Type A than in Type B individuals. ECG abnormalities were assessed by the Cardiac Infarction Injury Score (CIIS), which has predictive power for sudden death. In 100 healthy men aged 30-45 yr, the CIIS was related to cardiovascular risk factors such as age, blood pressure, smoking, family history of CHD and behaviour pattern groups defined by the Structured Interview (46 Type A, 20 Type X and 34 Type B subjects). The distribution of the CIIS was different among the behaviour pattern groups (p < 0.05) and was shifted towards higher ischemic scores in Type A subjects. These findings suggest that clinically asymptomatic persons with Type A behaviour have a greater probability of suffering ischemic heart disease and possible sudden death.