The effect of smoking and light activity on metabolism in men.

This experiment examined the metabolic effects of smoking during rest and light activity under naturalistic conditions. Thirty-nine male subjects first completed a submaximal graded exercise treadmill test to standardize activity level. Then 3 groups of subjects—smokers smoking (SS), smokers not smoking (SNS), and nonsmokers (NS)—were exposed to 3 stages of rest or 3 stages of light activity with order of rest or activity randomly determined over 2 different days. Energy expenditure was monitored continuously during these sessions. Significant increases in smokers' energy expenditure were observed during light activity when compared with smokers not smoking and nonsmokers. No differences were identified among groups at rest. These findings strengthen the conclusion that smoking or its components contribute to metabolic changes during typical levels of daily activity and suggest a mechanism for the frequently observed relationship between smoking status and body weight. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Automatic affective responses to smoking cues.

The authors examined automatic emotional reactions to smoking cues among 35 smokers and 25 nonsmokers (32 women and 28 men), using a novel implicit measure, the Affect Misattribution Procedure. Associative-learning theories of addiction suggest that smokers develop positive responses to cues linked to the rewarding effects of nicotine. Prior research, however, has yielded mixed evidence for whether smokers have favorable or unfavorable automatic responses to smoking cues. These findings may depend on the methods used to measure implicit responses. Using the Affect Misattribution Procedure, the authors found that nonsmokers responded to smoking cues with clear negative affect, whereas smokers' responses depended on individual differences in current smoking withdrawal. Smokers having withdrawal symptoms and those most motivated to smoke showed favorable emotional responses to smoking cues, but those with no withdrawal or low motivation to smoke showed negative responses. These results help integrate previous studies finding that smokers have negative automatic responses to cigarettes with those studies finding that smokers' responses were relatively positive. The results are important for theories that emphasize the role of cue conditioning in maintaining addiction because these theories assume, consistent with the current findings, that smoking cues can take on positive reward value. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of night smoking, sleep disturbance, and their co-occurrence on smoking outcomes.

Recent evidence suggests that smoking during the night is an indicator of nicotine dependence and predicts smoking cessation failure. Night smokers are likely to experience disturbance to their sleep cycle when they wake to smoke, but we are not aware of the prevalence of night smokers' self-reported sleep disturbance. Because sleep disturbance also predicts smoking cessation failure, we examined how the pre-cessation risk factors of night smoking and sleep disturbance, and their co-occurrence, predict smoking cessation failure in a 6-week double-blind randomized controlled trial examining whether naltrexone augments the efficacy of the nicotine patch (O'Malley et al., 2006). Smokers (N = 385) completed the Pittsburgh Sleep Quality Index (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989) and a single item of waking at night to smoke pre-cessation. Smoking status was determined at weeks 1, 6, 24, and 48 weeks after quitting. The two main findings were: (a) night smokers reported significantly greater sleep disturbance than nonnight smokers; and (b) smokers with co-occurring night smoking and sleep disturbance experienced significantly greater risk for smoking than smokers with neither risk factor. Results suggest that individuals who both wake during the night to smoke and report clinically-significant sleep disturbance represent a high-risk group of smokers. Future smoking cessation treatment might incorporate strategies related to managing these smokers' sleep habits and physiological dependence on nicotine in order to bolster their cessation outcomes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Effects of cigarette smoking on electrodermal orienting reflexes to stimulus change and stimulus significance

Skin conductance responses (SCRs) evoked by novel, signal, and frequent tone stimuli were measured in 20 male heavy smokers and 10 male nonsmokers over two sessions. All smokers abstained from smoking for 12 hr prior to each session. Half of the smokers smoked a cigarette of their preferred brand prior to SCR measurement in the first session, whereas the remaining smokers smoked in the second session. Nonsmokers did not smoke. Results combined across the two sessions indicated that abstinence was associated with selective depression of SCRs to the novel tone. Separate analyses of results from each session revealed that, in the second session, SCRs to both novel and signal tones were depressed in abstinent smokers, partially replicating previous findings. By contrast, first session results showed no significant effects of smoking or abstinence. Results were interpreted in terms of nicotine's effects on nonspecific arousal, with some reservations.     

The Generality of Working Memory Capacity: A Latent-Variable Approach to Verbal and Visuospatial Memory Span and Reasoning.

A latent-variable study examined whether verbal and visuospatial working memory (WM) capacity measures reflect a primarily domain-general construct by testing 236 participants in 3 span tests each of verbal WM. visuospatial WM, verbal short-term memory (STM), and visuospatial STM. as well as in tests of verbal and spatial reasoning and general fluid intelligence (Gf). Confirmatory' factor analyses and structural equation models indicated that the WM tasks largely reflected a domain-general factor, whereas STM tasks, based on the same stimuli as the WM tasks, were much more domain specific. The WM construct was a strong predictor of Gf and a weaker predictor of domain-specific reasoning, and the reverse was true for the STM construct. The findings support a domain-general view of WM capacity, in which executive-attention processes drive the broad predictive utility of WM span measures, and domain-specific storage and rehearsal processes relate more strongly to domain-specific aspects of complex cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of cigarette smoking and smoking deprivation on Wisconsin Card Sorting Test performance.

Wisconsin Card Sorting Test (WCST) performance was assessed in 24 heavy smokers and 12 nonsmokers recruited from universities in the US and Japan. Half of the smokers performed the WCST after abstaining from tobacco for 12 hrs, whereas the remaining smokers smoked a cigarette of their preferred brand immediately before the test. Nonsmokers did not smoke. The WCST was administered by computer, first with standard instructions and then a 2nd time with abbreviated instructions that specified the 3 sorting criteria. Results from the 2nd run indicated that abstinent smokers made significantly more perseverative responses and errors than did nonsmokers or smoking smokers. Results expand on previous findings of effects of smoking deprivation on human cognitive performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of tobacco smoking and abstinence on middle latency auditory evoked potentials

OBJECTIVE: To evaluate the effects of tobacco cigarette smoking and overnight abstinence on middle latency auditory evoked potentials among smokers and nonsmokers. METHODS: Groups of 9 to 10 adult male and female nonsmokers and smokers participated in the study. Each person volunteered for two laboratory sessions conducted in the early afternoon on 2 separate days. Smokers abstained from tobacco products 6 to 15 hours before the abstinent session and maintained their usual smoking behavior before the smoking session. The nonsmokers had a similar laboratory experience but sham smoked by means of inhaling air. Middle latency auditory evoked potentials were recorded from Cz to both ears as reference. RESULT: The latencies of the Na and Pa potentials during the smoking session were significantly (p < 0.01) shorter than those in abstinent smokers and nonsmokers. After smoking, peak-to-trough amplitudes for the V-Na, Na-Pa, and Pa-Nb potentials were larger than those after abstinence and significantly larger than those among nonsmokers. CONCLUSIONS: The shorter latencies of the middle latency brain wave components in the smoking session suggest faster processing of sensory information after cigarette smoking. Larger Pa amplitudes after cigarette smoking suggest a higher arousal level than that among partially abstinent smokers and nonsmokers.     

Can genetic risk information enhance motivation for smoking cessation? An analogue study.

Protection motivation theory and the extended parallel processing model are used to predict the motivational impact of information regarding a genetic susceptibility to heart disease. One hundred ninety-eight smokers read 1 of 3 vignettes: gene positive, gene negative, or standard smoking risk information. Analyses examined whether the impact of type of risk information was moderated by smokers' self-efficacy (SE) levels. Key outcomes were intention to quit and intention to attend an information session about quitting. There were significant main effects of SE and of receiving gene-positive risk information on intentions to quit. There was a significant Risk × SE interaction on intentions to attend an information session. SE was not associated with intentions to attend the information session for smokers in the gene-positive group. Intentions to attend the session were negatively associated with SE for smokers in the lower risk groups. Implications for using genetic risk information to motivate smoking cessation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of transdermal nicotine and concurrent smoking on cognitive performance in tobacco-abstinent smokers.

Smokers experience cognitive decrements during tobacco abstinence and boosts in performance on resumption of smoking. Few studies have examined whether smoking cessation treatments such as transdermal nicotine (TN) ameliorate these decrements or attenuate the cognitive effects of smoking. Identifying the effects of nicotine on these tobacco-related changes in performance could guide the development of more efficacious treatments. The purpose of this double-blind, randomized, laboratory study was to use process-specific cognitive tasks to examine the effects of TN and tobacco smoking on attention and working memory in overnight-abstinent smokers (N = 124; 54 women). Each participant completed 4 sessions lasting 6.5 hr corresponding to 0-, 7-, 14-, or 21-mg TN doses, and smoked a single cigarette 4 hr after TN administration. Outcome measures were administered before and after smoking and included tasks measuring attention (alerting, orienting, and executive function), working memory (verbal and spatial), and psychomotor function. Analysis of variance (p     

Working memory, attention control, and the n-back task: A question of construct validity.

The n-back task requires participants to decide whether each stimulus in a sequence matches the one that appeared n items ago. Although n-back has become a standard "executive" working memory (WM) measure in cognitive neuroscience, it has been subjected to few behavioral tests of construct validity. A combined experimental- correlational study tested the attention-control demands of verbal 2- and 3-back tasks by presenting n = 1 "lure" foils. Lures elicited more false alarms than control foils in both 2- and 3-back tasks, and lures caused more misses to targets that immediately followed them compared with control targets, but only in 3-back tasks. N-back thus challenges control over familiarity-based responding. Participants also completed a verbal WM span task (operation span task) and a marker test of general fluid intelligence (Gf; Ravens Advanced Progressive Matrices Test; J. C. Raven, J. E. Raven, & J. H. Court, 1998). N-back and WM span correlated weakly, suggesting they do not reflect primarily a single construct; moreover, both accounted for independent variance in Gf. N-back has face validity as a WM task, but it does not demonstrate convergent validity with at least 1 established WM measure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Occupation and smoking in college graduates.

The results of a study of 895 members of the Harvard Class of 1946, 13 years after graduation, with respect to the association of occupation and smoking behavior, indicate statistically significant differentiations between smokers and nonsmokers; between cigarette, cigar, and pipe smokers; and in accordance with degree or rate of cigarette smoking. The significance of these findings appears to relate to the influence of personality and constitution on smoking behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of internal and external control upon changes in smoking behavior.

Current evidence indicates that a personality measure which involves the extent to which a person perceives reinforcements as either internally or externally controlled (Internal-External scale, I-E) is significantly related to verbal as well as other behavioral measures of attitudes. The recent Surgeon General's report on smoking afforded an opportunity to study the relationship of the I-E variable to both attitudinal and behavior changes associated with smoking. The study was conducted 1 week after the release of the government report on smoking. Results indicate that (a) both male and female smokers are significantly more externally controlled than are nonsmokers; (b) smokers who were convinced by the evidence in the report had lower external control scores than those who were not convinced; and (c) among males, those who stopped smoking following the report were more internally oriented than those who continued smoking. It was concluded that the I-E dimension (which is independent of extroversion-introversion) may be an important personality variable in relation to smoking behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hostility, cigarette smoking, and responses to a lab-based social stressor.

High-trait hostility is associated with persistent cigarette smoking. To better understand mechanisms that may account for this association, we examined the effects of acute smoking abstinence and delayed versus immediate smoking reinstatement on responses to a social stressor among 48 low hostile (LH) and 48 high hostile (HH) smokers. Participants completed two laboratory sessions, one before which they had smoked ad lib and one before which they had abstained for the prior 12 hr. During each session, participants completed a stressful speaking task and then smoked immediately after the stressor or after a 15-min delay. The effect of immediate versus delayed smoking reinstatement on recovery in negative mood was significantly moderated by hostility. When reinstatement was delayed, HH participants showed significant increases in negative mood over time, whereas LH participants showed little change. When reinstatement was immediate, HH and LH smokers showed similar significant decreases in negative mood. Smoking abstinence did not moderate hostility effects. Cigarette smoking may prevent continuing increases in negative mood after social stress in HH smokers, which may partially explain their low rates of quitting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mutational spectra of a 100-base pair mitochondrial DNA target sequence in bronchial epithelial cells: a comparison of smoking and nonsmoking twins

Seventeen separate mitochondrial hot spot mutations in a 100-bp target sequence (mitochondrial bp 10,030-10,130) were detected and measured in bronchial epithelial cell samples isolated from smokers and nonsmokers. Among the individuals sampled were three pairs of monozygotic twins in which one twin had never smoked and had a nonsmoking spouse, and the other had a smoking history of >10 pack-years. Individual point mutations present at frequencies as low as 10(-6) were detected. Partially denaturing electrophoresis was used to separate mutant from nonmutant sequences on the basis of their melting temperatures, and the target sequence was subsequently amplified via high-fidelity PCR with Pfu DNA polymerase. Tests were performed to determine whether mismatch intermediates or DNA adducts present in the cellular DNA were converted to mutants during PCR. Hot spot mutations were clearly observed in bronchial epithelial cells, and the same hot spots were observed consistently in different samples. Significant numerical variability in the mutant fractions for individual mutants was observed among samples and are ascribed to unequal mitochondrial segregation in stem and transition cells. The mutational spectra in smokers' samples did not differ significantly from the mutational spectra in nonsmokers' samples for this 100 bp of mitochondrial DNA. No smoking-specific hot spots were detected. The overall mutant fractions in smokers' samples were not elevated compared to those of nonsmokers. As much variability was observed between two samples from the same individual's lung as between a sample from a smoker and a sample from a nonsmoker. These findings demonstrate that inhaled tobacco smoke does not induce prominent point mutations in this 100-bp target mitochondrial sequence in smokers' bronchial epithelial cells. Endogenous factors (e.g., DNA replication errors or DNA damage by endogenous reactive chemicals) are suggested to be more likely to represent the most important contributors to mitochondrial mutagenesis.     

Is smoking automatic? Demands of smoking behavior on attentional resources.

The role of attention in the production of smoking behavior was investigated. Experienced and novice smokers were asked to perform a reaction time (RT) task under 4 conditions: while smoking (smoking), while mimicking all aspects of smoking except inhaling (pseudosmoking), while simply holding a cigarette (holding), and while not smoking (baseline). Experienced smokers' RTs increased during the pseudosmoking and holding conditions compared with baseline but did not differ between the smoking and baseline conditions, suggesting that attentional resources were not required for typical smoking behavior but were required to alter or inhibit smoking behavior. Novice smokers' RTs were slower during both the smoking and pseudosmoking conditions but not the holding condition, suggesting that novice smokers require the use of resources to smoke. Experiment 2 demonstrated that the differences in RT across conditions could not be explained by differences in urges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The separate and combined effects of nicotine and alcohol on working memory capacity in nonabstinent smokers.

Research indicates that nicotine and alcohol are often used on the same occasion. However, the reasons for their concurrent use are not well understood. We hypothesized that one reason smokers use tobacco when they drink alcohol is to compensate for alcohol’s negative effects on processing capacity with nicotine’s enhancement of processing capacity. As such, the present study tested this theory by using an independent groups design to examine the separate and combined acute effects of alcohol and nicotine on working memory (WM) capacity. Nonabstinent daily smokers (n = 127) performed the counting span task (CSPAN) after consuming either an alcohol (men: 0.8 g/kg; women: 0.7 g/kg) or placebo beverage and smoking either nicotinized (1.14 mg nicotine, 15.9 mg tar) or denicotinized (.06 mg nicotine, 17.9 mg tar) cigarettes. Analyses revealed that smokers who smoked the nicotinized cigarettes performed significantly worse on the CSPAN task than smokers who smoked the denicotinized cigarettes. Although there was no main effect of alcohol on WM performance, women exhibited better WM performance than men after consuming alcohol whereas men performed better than women on the WM task after consuming the placebo beverage. Findings also revealed no interaction between the two substances on WM performance. Taken together, results suggest that nicotine impairs nonabstinent smokers’ verbal WM capacity and that gender moderates the effects of alcohol on WM. Furthermore, the present findings failed to support the notion that nicotine compensates for alcohol-related decrements in working memory capacity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Smokers' expectancies for smoking versus nicotine.

This study compared smokers' expectancies for the full act of smoking with those for nicotine per se by means of a word association task. Smokers (N = 201) were randomized to receive instructions to complete either "Smoking makes one ____." or "Nicotine makes one ____." with as many words as possible within 30 s. Results indicated that smokers held similar expectancies for smoking and nicotine; however, negative consequences (e.g., health risks) were more associated with smoking than with nicotine, and addiction expectancies were more associated with nicotine than with smoking. These findings suggest that smokers have a more realistic conceptualization of nicotine's role in smoking than had been indicated from earlier surveys. These findings have important implications for both nicotine-based and behavioral interventions, as well as for experimental designs that rely upon the perceived manipulation of nicotine content. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A meta-analysis of performance on simple span and more complex working memory tasks in Parkinson's disease.

The working memory (WM) concept has stimulated substantial research since Baddeley and Hitch advanced their model in 1974. There has also been growing interest in WM in Parkinson's disease (PD) where the brain structures considered important for WM are often compromised. However, it remains unclear how and to what degree WM is affected in PD. The authors used meta-analysis to clarify the research findings on WM in PD. The results confirmed that people with PD are impaired on tests of WM. This impairment is small for verbal span but moderate on complex verbal and both simple and complex visuospatial tasks. These data do not support the belief that WM impairment in PD is solely at the level of the central executive. However, our findings support the notion that impairment is more pronounced for visuospatial than verbal WM. A number of different interpretations of these results are discussed. It remains to be established what these statistically significant differences mean in terms of clinically significant levels of impairment in WM. Another important methodological issue that demands greater consideration in this area is that of sampling and the generalizability of results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interference, aging, and visuospatial working memory: The role of similarity.

Objective: Older adults' performance on working memory (WM) span tasks is known to be negatively affected by the buildup of proactive interference (PI) across trials. PI has been reduced in verbal tasks and performance increased by presenting distinctive items across trials. In addition, reversing the order of trial presentation (i.e., starting with the longest sets first) has been shown to reduce PI in both verbal and visuospatial WM span tasks. We considered whether making each trial visually distinct would improve older adults' visuospatial WM performance, and whether combining the 2 PI-reducing manipulations, distinct trials and reversed order of presentation, would prove additive, thus providing even greater benefit. Method: Forty-eight healthy older adults (age range = 60–77 years) completed 1 of 3 versions of a computerized Corsi block test. For 2 versions of the task, trials were either all visually similar or all visually distinct, and were presented in the standard ascending format (shortest set size first). In the third version, visually distinct trials were presented in a reverse order of presentation (longest set size first). Results: Span scores were reliably higher in the ascending version for visually distinct compared with visually similar trials, F(1, 30) = 4.96, p = .03, η2 = .14. However, combining distinct trials and a descending format proved no more beneficial than administering the descending format alone. Conclusions: Our findings suggest that a more accurate measurement of the visuospatial WM span scores of older adults (and possibly neuropsychological patients) might be obtained by reducing within-test interference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neutrophil chemokines in bronchoalveolar lavage fluid and leukocyte-conditioned medium from nonsmokers and smokers

Polymorphonuclear neutrophils (PMN) have been implicated in the pathogenesis of emphysema. The chemokines interleukin-8(IL-8), growth-related oncogene (GRO-alpha) and extractable nuclear antigen (ENA)-78 may be involved in the increased numbers of PMN in smokers' airspaces. The levels of these cytokines in bronchoalveolar lavage fluid (BALF) and bronchoalveolar lavage leukocyte conditioned medium (LCM), along with BALF PMN numbers in 12 smokers who abstained for 12 h (chronic smoking) or continued to smoke until I h before study (acute smoking) and seven nonsmokers were compared. Neutrophils in BALF increased in acute (1.96+/-0.53%, 0.99+/-0.32x10(6) cells) compared with chronic smokers (0.59+/-0.25%, 0.61+/-0.24x10(6) cells, p<0.05 nonsmokers) and nonsmokers (0.79+/-0.29%, 0.05+/-0.01x 10(6) cells, p<0.05). There were no differences in IL-8 or GRO-alpha in BALF between smokers and nonsmokers. ENA-78 levels were lower in smokers (p=0.006). There was no difference in IL-8, GRO-alpha or ENA-78 in LCM from unstimulated cells in smokers versus nonsmokers. After stimulation with lipopolysaccharide (LPS) 10 ng mL(-1), IL-8 release in acute smokers (p=0.04) and GRO-alpha release in smokers (p=0.009) were significantly higher than in nonsmokers. Following stimulation with LPS 100 ng.mL(-1), GRO-alpha release was higher in smokers (p=0.03) and increased further in acute smokers (p=0.02 versus nonsmokers, p=0.04 versus chronic smokers) and ENA-78 release increased in smokers (p=0.02 versus non-smokers). In conclusion, influx of polymorphonuclear neutrophils into smokers' airspaces is an acute phenomenon and neutrophil chemokine release from mixed bronchoalveolar lavage leukocytes is influenced by cigarette smoking and endotoxins.