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1.
Whereas the smoking prevalence rates in the general population are declining, rates among people diagnosed with attention-deficit/hyperactivity disorder (ADHD) continue to be elevated. Previous research has shown that nicotine may improve attention and mood, suggesting that nicotine may help ameliorate the attentional and emotional problems associated with ADHD. The present study examined the effects of nicotine with and without stimulant medication on ADHD symptoms, moods, and arousal in the everyday lives of smokers with ADHD. A total of 10 smokers with ADHD who were being treated with stimulant medication were asked to abstain from smoking while participating in the study. Participants underwent four conditions in randomized order: (a) Nicotine patch+stimulant medication, (b) nicotine patch only, (c) placebo patch+stimulant medication, and (d) placebo patch only. Each condition continued for 2 days, during which self-reports of ADHD symptoms and moods were obtained using electronic diaries. Lightweight ambulatory monitors recorded cardiovascular activity at each diary entry. Smoking abstinence was verified by expired carbon monoxide and salivary cotinine analysis. Results showed that nicotine patches and stimulant medication alone and in combination reduced difficulty concentrating and core ADHD symptoms compared with placebo patch only. Borderline improvement in impatience and self-control was seen with nicotine patch administration primarily on day 1. Nicotine patches also tended to elevate systolic and diastolic blood pressure compared with placebo patch during day 2. The findings suggest that smokers with ADHD experience nicotine-related reductions in ADHD symptoms during their everyday lives.  相似文献   

2.
Given that nicotine reduces negative affect, one would expect nicotine to have different effects on brain responses to emotionally negative stimuli than it does on responses to emotionally neutral or positive stimuli. However, no studies have assessed this possibility. The present study assessed the effects of nicotine patch versus placebo patch on brain event-related potential (ERP) responses to emotion-inducing negative, positive, and neutral color pictures in 16 smokers in a double-blind, counterbalanced, within-subjects design. The study included four experimental sessions. After overnight smoking deprivation (12 hr or more), active nicotine patches were applied to participants during one of the first two sessions and during one of the last two sessions. Placebo patches were applied during the other two sessions. Nicotine reduced frontal ERP processing voltage negativity (from 144-488 ms poststimulus onset) evoked by viewing emotionally negative pictures to a greater extent than it did when emotionally neutral pictures were viewed, whereas it had no effect on processing negativity evoked by positive pictures. Nicotine also enhanced P390 amplitudes evoked by emotionally negative pictures more than it did when emotionally neutral and positive pictures were viewed. Across picture types, nicotine (relative to placebo) reduced N300 amplitude (more at anterior and dorsal sites) and increased P390 amplitude. Overall, nicotine influenced ERPs to emotionally neutral and positive pictures less than it did to negative pictures.  相似文献   

3.
The Situation x Trait Adaptive Response (STAR) model hypothesizes that nicotine reduces negative and enhances positive affect to a greater degree in situations involving internally driven attention, as when stressor stimuli are distal (past or future), thereby allowing nicotine-primed biasing of attentional processing away from negative and toward positive stimuli. To test this hypothesis, the effects of nicotine were assessed in 64 smokers and 64 never-smokers, half of whom viewed emotionally negative pictures in a no-choice picture attention task that required them to focus on the picture stressors. The other half viewed the same stimuli in a two-choice picture attention task that presented stressor pictures in one visual field and simultaneously presented positive or neutral pictures in the other visual field. Participants received a nicotine patch during one session and a placebo patch during the other session. Nicotine modulated affect only in smokers. In smokers, compared with placebo, nicotine patch reduced negative affect more during the distal periods (between stressors) than during actual stressor exposure and in women reduced negative affect more when the proportion of negative stimuli was low. Nicotine also enhanced positive affect more during distal than proximal stressors. Nicotine tended to reduce eye-gaze at negative pictures, especially when the alternative picture was positive. The overall findings are consistent with the view that nicotine biases attention away from negative stimuli when equally salient positive or benign stimuli are present.  相似文献   

4.
We sought to determine whether polymorphism in the serotonin transporter (5HTT) gene is associated with attentional bias toward smoking-related stimuli in current smokers and ex-smokers, using a modified Stroop task and an attentional blink task to measure selective processing of smoking-related stimuli. All participants attended a single testing session during which they completed the modified Stroop and attentional blink tasks to index attentional bias for smoking-related stimuli, in counterbalanced order. The experimental design included two between-subjects factors of smoking status (current smoker, ex-smoker) and 5HTT genotype (short, long). Smoking status x genotype interactions were significant on both the modified Stroop (p = .046) and the attentional blink (p = .006) tasks. On the modified Stroop task, we found a significant effect of 5HTT genotype on color-naming interference among ex-smokers (p = .018) but not current smokers (p = .989). On the attentional blink task, we found a significant effect of 5HTT genotype for current smokers (p = .028), whereas among ex-smokers this effect did not reach statistical significance, although it constituted a trend (p = .086). Our data provide tentative support for a moderating influence of 5HTT genotype on attentional bias for smoking-related stimuli in ex-smokers. This finding may account for inconsistent reports of attentional bias among ex-smokers.  相似文献   

5.
Aversive and smoking-related stimuli are related to smoking urges and relapse and can be potent distractors of selective attention. It has been suggested that the beneficial effect of nicotine replacement therapy may be mediated partly by the ability of nicotine to reduce distraction by such stimuli and thereby to facilitate attention to task-relevant stimuli. The present study tested the hypothesis that nicotine reduces distraction by aversive and smoking-related stimuli as indexed by the parietal P3b brain response to a task-relevant target digit. We assessed the effect of nicotine on distraction by emotionally negative, positive, neutral, and smoking-related pictures immediately preceding target digits during a rapid visual information processing task in 16 smokers in a double-blind, counterbalanced, within-subjects design. The study included two experimental sessions. After overnight smoking deprivation (12+ hr), active nicotine patches were applied to participants during one of the sessions and placebo patches were applied during the other session. Nicotine enhanced P3b responses associated with target digits immediately subsequent to negative emotional pictures bilaterally and subsequent to smoking-related pictures only in the right hemisphere. No effects of nicotine were observed for P3bs subsequent to positive and neutral distractor pictures. Another measure of attention, contingent negative variation amplitude in anticipation of the target digits also was increased by nicotine, especially in the left hemisphere and at posterior sites. Together, these findings suggest that nicotine reduces the distraction by emotionally negative and smoking-related stimuli and promotes attention to task-related stimuli by modulating somewhat lateralized and task-specific neural networks.  相似文献   

6.
Although converging lines of evidence suggest that nicotine and mood are related at a fundamental biological level, this link has not been reliably demonstrated in laboratory studies. In this study, startle probe methodology was used to examine the effects of nicotine administration and deprivation on emotional processes associated with motivation. Smokers (N = 115) completed four laboratory sessions crossing deprivation (12-hr deprived vs. nondeprived) with nicotine spray (active vs. placebo). Participants viewed affective pictures (positive, negative, neutral) and pictures involving cigarette cues, while startle probes were administered. Deprivation decreased startle responding to cigarette cues, suggesting an activation of appetitive processes. Nicotine administration suppressed overall startle responding during deprivation. In addition, during deprivation, random exposure to negative stimuli over two blocks of trials resulted in decreased adaptation of the startle response, suggesting that some sensitization to negative emotional cues may take place during nicotine withdrawal. These effects are consistent with formulations of addiction, stressing that withdrawal may both increase the reinforcement salience of smoking stimuli and decrease habituation to negative emotional stimuli.  相似文献   

7.
Effects of substance use are typically assumed to be related to pharmacological actions. However, beliefs about the drug content of a substance may strongly influence subjective and reinforcing responses to that substance (i.e., "placebo" effects). We examined the subjective and reinforcing effects of a nasal spray containing no nicotine as a function of instructions about the nicotine content of the spray (Told Nicotine vs. Told No Nicotine). Smokers (n=49) not interested in quitting smoking abstained overnight prior to a single session in which they were randomly assigned to one of three groups, involving one of the two instructional sets or a group that got no spray. Following dose instructions, subjects in the two spray groups were administered one set of four sprays from the spray bottle and then rated them intermittently on items related to "reward" (e.g., "liking", amount they would pay for more) and other effects. At the same time points, they also rated mood, craving, and withdrawal, and had heart rate and blood pressure measured. Reinforcement was then determined by the number of ad libitum sprays they self-administered during a 20-min period. The no-spray group simply rested quietly during the session, while measures were assessed at the same time points as subjects in the other two groups. Those in the Told Nicotine group reported greater spray ratings of "how much nicotine," "liking," "satisfying," "buzz/head rush," and "similar to smoking" compared with the Told No Nicotine group. Craving decreased more for those Told Nicotine versus those Told No Nicotine, but also decreased more for those Told No Nicotine compared with the no spray group. There were no significant differences in amount they would pay for more sprays, withdrawal, mood, cardiovascular responses, or in spray self-administration. These results show that instructions about the nicotine content of a novel delivery device (nasal spray) can influence self-reported spray ratings and reduce craving but are limited with respect to effects on other measures of drug response.  相似文献   

8.
The effects of nicotine, distractor type, and dopamine type-2 receptor (DRD2) genotype on rapid visual information processing (RVIP) task performance were assessed in habitual smokers. Four RVIP tasks differed in terms of distractor location (central vs. peripheral) and distractor type (numeric vs. emotional). Each participant performed each of the tasks on two different days, once while wearing an active nicotine patch and once while wearing a placebo patch. Overall, the nicotine patch produced more accurate detection of and faster reaction times to target sequences; however, these effects varied with distractor type and genotype. Nicotine speeded reaction time more with left-visual-field (LVF) than right-visual-field (RVF) emotional distractors but speeded reaction time more with RVF than LVF numeric distractors, especially when the distractor digit matched the target sequence in terms of numeric oddness or evenness. Nicotine tended to facilitate performance more in individuals with at least one A1 allele than in homozygous A2A2 individuals, especially with numeric distractors presented to the left hemisphere. Nicotine tended to reduce distraction by negative stimuli more than other types of stimuli. Few gender differences were observed. The overall pattern of results was consistent with the view that nicotine modulates selective attention or subsequent information processing in a manner that depends partly on the emotional versus numeric nature of task distractors, DRD2 genotype, and the brain hemisphere that initially processes the distractors (visual field of distractor).  相似文献   

9.
Behavioral studies have shown that nicotine enhances performance in sustained attention tasks, but they have not shown convincing support for the effects of nicotine on tasks requiring selective attention or attentional control under conditions of distraction. We investigated distractibility in 14 smokers (7 females) with event-related brain potentials (ERPs) and behavioral performance measures extracted from an auditory discrimination task requiring a choice reaction time response to short- and long-duration tones, both with and without embedded deviants. Nicotine gum (4 mg), administered in a randomized, double-blind, placebo-controlled crossover design, failed to counter deviant-elicited behavioral distraction (i.e., slower reaction times and increased response errors), and it did not influence the distracter-elicited mismatch negativity, the P300a, or the reorienting negativity ERP components reflecting acoustic change detection, involuntary attentional switching, and attentional reorienting, respectively. Results are discussed in relation to a stimulus-filter model of smoking and in relation to future research directions.  相似文献   

10.
Smoking during pregnancy remains a major public health concern and is associated with numerous adverse effects. Recently the clearance of nicotine and cotinine was shown to be substantially increased in pregnant women compared with nonpregnant controls. The present study investigated the usefulness of the rabbit for studying the molecular basis for the observed changes in nicotine and cotinine disposition during pregnancy. Nicotine was largely metabolized to cotinine in rabbit liver microsomes (approximately 50% of total metabolism); significant amounts of nicotine-N'-oxide and nornicotine also were detected. The conversion of nicotine to cotinine also was detected in rabbit placental and fetal liver microsomes, albeit at only a fraction of the rate found in adult rabbit liver microsomes. The major products of cotinine metabolism in rabbit liver microsomes were 5'-hydroxycotinine, cotinine-N'-oxide, and norcotinine. Differences between human and rabbit liver were most apparent for cotinine. The major human metabolite, 3'-hydroxycotinine, was formed at only low levels in rabbit liver microsomes. Pregnancy had no effect on the metabolism of nicotine or on the expression of CYP2A6 immunoreactive proteins in rabbit liver microsomes. These studies provide a complete quantitative assessment of nicotine metabolism in rabbit liver microsomes and suggest that the rabbit may not be an appropriate animal model to study the effects of pregnancy on nicotine and cotinine metabolism. However, a molecular understanding of these effects is essential for prediction of the pharmacological and toxicological consequences of smoking during pregnancy.  相似文献   

11.
The subjective and reinforcing effects of drugs of abuse may depend partly on their rate of onset, with faster acting formulations typically producing stronger effects than slower ones. In this within-subjects study, we examined the acute effects of nicotine replacement therapy via nicotine nasal spray (fast delivery) vs. transdermal nicotine patch (slow delivery) on craving, withdrawal, cardiovascular responses, subjective ratings, and reinforcing effects of smoking. Smokers (N=30) not seeking treatment participated in three sessions, each after overnight smoking abstinence, involving 14-mg nicotine (Nicoderm) or placebo patch, followed 4 hr later by intermittent administration of nicotine (Nicotrol) or placebo nasal spray. Specifically, the three group comparisons were nicotine patch condition (with placebo spray), nicotine spray condition (with placebo patch), and placebo condition (placebo spray and patch). Nicotine patch and nicotine spray were never administered in the same session. Blood nicotine levels were similar between nicotine patch and nicotine spray conditions, by design. Heart rate and systolic blood pressure were higher following nicotine spray vs. the other conditions, as hypothesized. However, other than reductions in craving related to nicotine spray and patch at some points, no differences between conditions were observed in withdrawal, subjective effects of sprays and smoking, or smoking reinforcement assessed by a computer task. Thus, under these acute conditions, the speed of nicotine delivery from nasal spray vs. patch differentially affected cardiovascular responses and perhaps craving but did not influence withdrawal, subjective ratings, and smoking reinforcement.  相似文献   

12.
The present study investigated the possibility of forming a multidimensional scale for the measurement of nicotine dependence among adolescents, based on the modified Fagerstr?m Tolerance Questionnaire (mFTQ) and the Hooked on Nicotine Checklist (HONC). A survey was conducted among 33 Dutch secondary schools, resulting in 2,041 smokers who completed the questionnaire. Motivation to quit and number of quit attempts were assessed and used as convergent construct variables for the construct of nicotine dependence. The findings show that combining the items of the mFTQ and the HONC results in three distinct dimensions: behavioral aspects of nicotine dependence, craving, and nervousness during abstinence. We examined this new multidimensional model in a second sample using confirmatory factor analysis. The new multidimensional measure fitted the data satisfactorily and showed good psychometric properties. Results of this study support the notion that nicotine dependence among adolescents is multidimensional.  相似文献   

13.
The present study correlates empirically constructed prospective adolescent smoking trajectories with indicators of nicotine dependence assessed in adolescence and in adulthood. Excluding individuals who reported no smoking during repeat assessment (nonadopters), we identified five smoking trajectory groups: experimenters (n=116, 48.5%), late increasers (n=39, 16.3%), early increasers (n=37, 15.5%), quitters (n=22, 9.2%), and persistent smokers (n=25, 10.5%). Higher frequency of nicotine dependence symptoms in adolescence occurred in the quitters and persistent smokers groups, who smoked at higher levels relative to the experimenters, late increasers, and early increasers groups, who reported a similar frequency of nicotine dependence symptoms and smoked at low levels. Lifetime nicotine dependence was assessed in adulthood in lifetime daily smokers using the Fagerstr?m Test for Nicotine Dependence (FTND) and the Nicotine Dependence Scale (NDS). Lifetime FTND levels were similar across trajectory groups. Relative to experimenters, all remaining smoking trajectory groups had higher NDS levels that were similar to one another. These results suggest that higher levels of adolescent nicotine dependence were associated with heavier smoking trajectory groups, and that regardless of trajectory group membership, smoking more than a few cigarettes per week throughout adolescence resulted in similar levels of lifetime nicotine dependence as measured by the FTND and NDS.  相似文献   

14.
The goal of this study was to identify associations among self-reported nicotine exposure, nicotine addiction, and actual nicotine intake as measured by salivary cotinine levels in adolescent smokers. A total of 170 adolescent smokers with a mean age of 15 years were recruited from seven northern Californian public high schools. Data were collected on smoking behaviors, addiction, craving, and withdrawal. Nicotine dependence was assessed using a modified teen Fagerstr?m Tolerance Questionnaire (mtFTQ), a modified Nicotine Dependence Syndrome Scale (mNDSS), and a simple self-rating. Withdrawal was assessed using the Minnesota Withdrawal Questionnaire, and craving was assessed using a survey created by the authors. Salivary cotinine levels were collected from and analysed in participants who self-identified as smokers; data from the 54 participants who smoked in the past 4 days and whose salivary cotinine levels were greater than 0.1 ng/ml were used in the analysis. Among this group of adolescent smokers, the mean number of cigarettes smoked per day was 3.51 (SD = 3.44) and the mean level of salivary cotinine was 44.1 ng/ml (Mdn = 24.2). Even at this low level of nicotine exposure, cotinine was highly correlated with measures of nicotine dependence such as the mtFTQ (r = 0.497, p = .001), NDSS (r = 0.439, p = .002), timing of craving in the morning (r = -0.601, p = .000), and self-rated addiction (r = 0.562, p = .000). Most interesting, cotinine levels reached a plateau at around 4-5 cigarettes/day.  相似文献   

15.
Many smokers are not ready to quit but are interested in changing their smoking behavior, particularly if such a change is associated with a reduction in health risk. The present study evaluated the efficacy of the nicotine inhaler in reducing smoking. Exploratory studies assessed whether reduction in smoking was associated with reduction in markers of disease risk. A total of 429 healthy smokers (smoking at least 20 cigarettes/day) were randomly assigned to either nicotine-containing or placebo inhalers, which subjects were allowed to use ad libitum for up to 1 year. The nicotine inhaler was significantly superior to placebo in achieving reduction in daily cigarette consumption by at least 50% after 4 months, compared with baseline (18% vs. 8%, p = .004). Active treatment promoted smoking cessation: 8% of subjects in the nicotine group and 1% in the placebo group were abstinent at month 15. Throughout the study, smoking reduction, per se, independent of treatment group, was associated with a statistically significant decrease in exhaled carbon monoxide and serum cotinine and thiocyanate. Smoking reduction also improved established risk markers for cardiovascular disease over 4 months. The incidence of adverse events did not differ significantly between the active and placebo groups. The most common treatment-related adverse events were throat irritation and cough. In conclusion, the nicotine inhaler can help smokers who are unable or unwilling to quit to reduce daily cigarette consumption, which may be a health benefit on its own and may further promote quitting.  相似文献   

16.
尼古丁是烟草的主要生物碱,其生物学功能获得了广泛的关注。近年的研究表明,尼古丁与帕金森病的发病率之间呈现出显著的负相关性。通过综述流行性病学调查、帕金森病动物模型及尼古丁起作用的相关分子机制等方面的研究,提出了尼古丁在帕金森病治疗过程中存在的问题及潜在的作用。   相似文献   

17.
烟碱是烟叶和烟气中重要的具有生理活性的化学成分,大幅度降低烟碱含量对烟叶化学组成和感官质量会产生显著影响。目前虽然可通过遗传育种、遗传工程、农艺调控和化学萃取等途径在一定程度上实现低/超低烟碱含量烟叶生产,但能否大规模投入使用尚存在不确定性。本文针对烟碱管控这一国际烟草界热点问题,围绕低烟碱烟叶生产途径和特点,低烟碱烟叶化学成分和烟叶质量变化等进行了全面综述,并对低烟碱烟叶生产和应用的可行性和局限性进行了分析和展望。   相似文献   

18.
Nicotine has been recognized for years as being pharmacologically responsible for the sympathoexcitatory effects of smoking. The effects of nicotine supplementation on myocardial blood flow as assessed by positron emission tomography are, however, unknown. We tested the hypothesis that nicotine substitution could interfere with myocardial blood flow autoregulation at rest in habitual smokers at risk of coronary artery disease. The short-term effect of a 4-mg nicotine tablet on myocardial blood flow was quantified with 13N ammonia positron emission tomography in 12 smokers with high cardiovascular risk (10 males and 2 females; mean age = 58+/-8 years; SCORE risk >5%). Nicotine increased systolic blood pressure from 129+/-7 to 134+/-7 mmHg (p = .03) and heart rate from 67+/-2 to 69+/-2 bpm (p = .04). As a result, nicotine raised the rate-pressure product from 8618+/-622 to 9285+/-627 bpm mmHg (p = .02). Nicotine tended to increase myocardial blood flow in the circumflex artery territory, but this effect failed to reach the level of statistical significance (from 0.56+/-0.06 to 0.63+/-0.03 ml/min/g; p>.15). This trend disappeared when myocardial blood flow was normalized for the rise in the rate-pressure product. Global myocardial perfusion, normalized for the changes in rate-pressure product, remained unchanged from 0.70+/-0.06 at baseline to 0.71+/-0.03 (ml/min/g)/(bpm mmHg) after nicotine. Nicotine supplementation in habitual smokers with high cardiovascular risk increased myocardial work without compromising resting myocardial blood flow autoregulation.  相似文献   

19.
Greater sensitivity to early exposure to tobacco smoking may predict higher risk of becoming nicotine dependent. The most common measure of this sensitivity is the retrospective self-report Early Smoking Experiences (ESE) questionnaire. We examined the relationship between responses to the retrospective ESE and prospectively assessed sensitivity to nicotine via nasal spray in young adult nonsmokers (N = 58) with modest lifetime smoking experience (>0 but < or =10 lifetime uses). Nicotine spray (0 vs 10 microg/kg) was used due to ethical and practical concerns with administering tobacco smoke to nonsmokers. Responses to cigarette smoking on the retrospective ESE items of pleasant, unpleasant, nausea, relaxed, dizzy, and buzzed were compared with prospectively assessed nicotine spray effects (NSE) on the same responses. ESE responses were also compared with subjective spray ratings of nicotine reward (e.g., "liking") and perception (e.g., "feel the effects"), cardiovascular activity, and nicotine reinforcement via a nicotine spray choice procedure. Results showed that the retrospective ESE items of dizzy and buzzed were each associated with greater prospective NSE dizzy and buzzed responses to nasal spray nicotine. However, the other four ESE items were unrelated to the corresponding NSE items. Responses to some ESE items were also related to prospective nicotine spray reward and perception, but no ESE item was related to the cardiovascular or reinforcing effects of nicotine spray. These findings show that two of six retrospective ESE items, dizzy and buzzed, predicted the same prospectively assessed responses to acute nicotine via spray in young adult nonsmokers and may reflect a stable and reliable response to nicotine intake.  相似文献   

20.

Background

Smoking is common in young people, particularly in disadvantaged groups, and continued smoking has a major impact on quality and quantity of life. Although many young smokers want to stop smoking, little is known about the design and effectiveness of cessation services for them.

Objective

To determine whether nicotine replacement therapy (NRT) when combined with counselling is effective in young smokers in a deprived area of Nottingham, UK

Methods and subjects

We surveyed smoking prevalence and attitudes to smoking and quitting in young people accessing an open access youth project in a deprived area of Nottingham, and used the information gained to design a community based smoking cessation service incorporating a randomised controlled trial of nicotine patches against placebo given in association with individual behavioural support. We resurveyed smoking prevalence among project attendees after completing the pilot study.

Results

Of 264 young people surveyed (median age 14 years, range 11–21), 49% were regular smokers. A total of 98 young people were recruited and randomised to receive either active nicotine patches on a six week reducing dose regimen (49 participants), or placebo (49 participants). Adherence to therapy was low, the median duration being one week, and 63 participants did not attend any follow up. At four weeks, five subjects receiving active NRT and two receiving placebo were abstinent, and at 13 weeks none were. Adverse effects were more common in the active group but none were serious. Smoking prevalence among 246 youth project attendees surveyed after the trial was 44%.

Conclusions

This study suggests that NRT in this context is unlikely to be effective in young smokers, not least because of low adherence to therapy. It also suggests that young smokers want help with smoking cessation, but that establishing the efficacy of smoking cessation services for young people who need them most will be very difficult.  相似文献   

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