Evidence that episodic memory impairment during tobacco abstinence is independent of attentional mechanisms

Previous studies have demonstrated reductions in episodic memory during nicotine withdrawal. However, these studies have been unable to dissociate memory reductions from losses in attention associated with tobacco abstinence. In the present study, the authors sought to determine whether episodic memory reduction is a primary effect of nicotine withdrawal during tobacco abstinence. Heavy smokers were tested when smoking normally and following 24 hrs of abstinence. Participants were tested with a recognition memory task in which items were studied under full and divided attention conditions. Forward digit span and backward digit span were also included as control measures. Withdrawal was associated with a reduction in memory performance that was independent of attention at encoding. The authors conclude that impairment of episodic memory is a primary effect of nicotine withdrawal during tobacco abstinence. Further research is required to determine if this is associated with continued use of tobacco and cessation failures.     

Effects of acute and prolonged opiate abstinence on extinction behaviour in rats.

We examined the role of withdrawal in relapse to drug-seeking and drug-taking by testing the effects of opiate abstinence on extinction behaviour in rats trained to self-administer heroin. Male Long-Evans rats responded for IV heroin under a heterogeneous chain (VI 120 s; FR 1) schedule in which "seeking" responses preceded a "taking" response which produced a drug infusion. Responding was then measured in extinction during acute (6, 12, and 24 hr) and prolonged (3, 6, 12, and 25 day) abstinence. Sucrose consumption and somatic withdrawal were assessed at each testing period. During acute abstinence, responses on the "drug-seeking" manipulandum increased at 24 hr, whereas responses on the "drug-taking" manipulandum increased at 6 hr. Both responses were elevated during the 12-day abstinence test. Sucrose consumption was reduced and somatic withdrawal scores were increased in opiate-experienced rats at each test period. Results suggest that heroin abstinence has different effects on drug-seeking and drug-taking and that these effects do not temporally coincide with somatic measures of opioid withdrawal.     

Pharmacologic and Behavioral Withdrawal From Addictive Drugs

ABSTRACT— Recent theories suggest that drug withdrawal does not motivate drug use and relapse. However, data now show that withdrawal produces complex changes over time in at least two symptoms (i.e., negative affect and urges) that are highly predictive of relapse. Evidence suggests that falling levels of the drug in the blood and interruption of the drug self-administration ritual both affect these symptoms. Both of these forms of withdrawal motivate renewed drug use in addicted individuals.     

Addiction motivation reformulated: an affective processing model of negative reinforcement

This article offers a reformulation of the negative reinforcement model of drug addiction and proposes that the escape and avoidance of negative affect is the prepotent motive for addictive drug use. The authors posit that negative affect is the motivational core of the withdrawal syndrome and argue that, through repeated cycles of drug use and withdrawal, addicted organisms learn to detect interoceptive cues of negative affect preconsciously. Thus, the motivational basis of much drug use is opaque and tends not to reflect cognitive control. When either stressors or abstinence causes negative affect to grow and enter consciousness, increasing negative affect biases information processing in ways that promote renewed drug administration. After explicating their model, the authors address previous critiques of negative reinforcement models in light of their reformulation and review predictions generated by their model.     

Prospective analysis of early lapse to drinking and smoking among individuals in concurrent alcohol and tobacco treatment

The aims of the current study were to examine, prospectively, (a) dynamic changes in affective state, self-efficacy, and urge in the hours before initial smoking and drinking lapses among individuals in concurrent alcohol and smoking treatment, and (b) the extent to which self-efficacy, urge to use, and/or the use of one substance predicted lapse to the other substance. Ninety-six men and women recruited for a clinical trial of concurrent alcohol and tobacco treatment were eligible for inclusion. Only data from those who experienced an initial lapse to drinking (n=29) or smoking (n=32) were included. Two outpatient substance abuse clinics provided concurrent alcohol and smoking treatment on a weekly basis for three months. Ecological Momentary Assessment (EMA) methods were employed over a 28-day monitoring period to assess antecedents to first drink, and a 14-day monitoring period was examined for initial smoking lapses. Baseline and EMA measures of positive and negative affect, alcohol/smoking urge, alcohol/smoking abstinence self-efficacy, nicotine withdrawal, and quantity/frequency of alcohol and tobacco use were examined as lapse predictors. Analyses of EMA ratings controlled for the corresponding baseline measure. Smoking lapse among individuals in concurrent alcohol and tobacco treatment was foreshadowed by higher urges to smoke, lower positive mood, and lower confidence to resist smoking. Drinking lapse was preceded by lower confidence to resist smoking, but only among individuals who reported recent smoking. Concurrent alcohol and smoking treatment should focus on the enhancement of abstinence self-efficacy, positive mood, and the curbing of urges in order to offset lapse risk.     

Positive reactions to tobacco predict relapse after cessation

Among chronic smokers, individual differences in subjective reactions to smoking may characterize important facets of nicotine dependence that relate to abstinence-induced craving, withdrawal symptom profiles, and risk for relapse. Although the negative reinforcing properties of smoking have achieved prominent positions in models of relapse (Baker, Brandon, & Chassin, 2004), vulnerability to relapse risk may also arise from seeking positive reinforcement from smoking (Shiffman & Kirchner, 2009). In this study, 183 cessation-motivated smokers provided subjective craving, positive and negative reactions to standardized cigarettes following overnight abstinence. Level of craving, negative mood, and positive mood after overnight abstinence were significantly predictive of withdrawal on quit-day. Increased positive reactions to smoking were uniquely predictive of relapse after quitting (Hazard Ratio = 1.22, p < .001). Individual differences in positive reactions to smoking may be important markers of neurobiological systems that promote dependence and interfere with cessation efforts.     

Evidence That Episodic Memory Impairment During Tobacco Abstinence Is Independent of Attentional Mechanisms

Previous studies have demonstrated reductions in episodic memory during nicotine withdrawal. However, these studies have been unable to dissociate memory reductions from losses in attention associated with tobacco abstinence. In the present study, the authors sought to determine whether episodic memory reduction is a primary effect of nicotine withdrawal during tobacco abstinence. Heavy smokers were tested when smoking normally and following 24 hrs of abstinence. Participants were tested with a recognition memory task in which items were studied under full and divided attention conditions. Forward digit span and backward digit span were also included as control measures. Withdrawal was associated with a reduction in memory performance that was independent of attention at encoding. The authors conclude that impairment of episodic memory is a primary effect of nicotine withdrawal during tobacco abstinence. Further research is required to determine if this is associated with continued use of tobacco and cessation failures.     

Manipulating smoking motivation: impact on an electrophysiological index of approach motivation.

A chief goal of this research was to determine whether stimuli and events known to enhance smoking motivation also influence a physiological variable with the potential to index approach motivation. Asymmetry of electroencephalographic (EEG) activity across the frontal regions of the 2 hemispheres (left minus right hemisphere activation) was used to index approach motivation. In theory, if EEG asymmetry sensitively indexes approach dispositions, it should be influenced by manipulations known to affect smoking motivation, that is, exposure to smoking cues and tobacco deprivation. Seventy-two smokers participated in this research and were selectively exposed to a smoking-anticipation condition (cigarettes plus expectation of imminent smoking) following either 24 hr of tobacco withdrawal or ad libitum smoking. Results indicated that EEG asymmetry was increased by smoking anticipation and that smoking itself reduced EEG asymmetry. Results also suggested that smoking anticipation increased overall (bihemispheric) EEG activation. Results were interpreted in terms of major theories of drug motivation.     

Gender-related processes and drug use: self-expression with parents, peer group selection, and achievement motivation

This investigation examined gender differences in communication with parents, peer group selection, and academic motivation as related to drug use among adolescents (290 girls, 237 boys; age range = 12-19 years). For girls, increased self-expression with parents was associated with greater academic motivation, more academically motivated friends, fewer drug-using friends, and less overall drug use. For boys, self-expression was positively related to academic motivation. For both boys and girls, having drug-using friends predicted increased drug use, while having academically motivated friends predicted decreased drug use. For girls only, age and academic motivation predicted drug use as well. These findings indicate that peer group selection and academic motivation may mediate the relationship between drug use and parent-adolescent communication for girls only.     

Effects of pay resets following drug use on attendance and hours worked in a therapeutic workplace

This secondary data analysis examined effects of an abstinence contingency on participation in a therapeutic workplace. Participants exposed to a pay reset after drug use did not differ in overall attendance from participants who were not exposed to a pay reset after drug use; however, they initially worked less after a pay reset than participants who did not receive a pay reset, and their attendance increased as their pay increased. Overall participation was not influenced by the abstinence contingency, but transient decreases in attendance occurred.     

LISTENING TO NICOTINE:

Abstract— In recent years, theoretical models of drug motivation and drug dependence have downplayed the role of withdrawal symptoms in the maintenance of addiction. During this same period, strong links between drug use and measures of negative affect have been uncovered in empirical research. In this article we examine these trends in the context of research on smoking. Evidence is presented from two recent studies on smoking relapse that highlight the intimate connection between withdrawal symptomatology and negative affect Specifically, these studies reveal that (a) single-occasion measures of withdrawal symptoms or other markers of physical dependence do not contribute incremental validity in preceding relapse relative to measures of negative affect (b) the trajectory of withdrawal symptoms is highly idiosyncratic, (c) exacerbations cannot be tightly coupled with pharmacological events. (d) the temporal dynamics of withdrawal reflect fluctuations in negative affect, and (e) differences in the trajectory of withdrawal symptoms index relapse vulnerability. We conclude that a broadened view of withdrawal recognizing its probable affective bases will enhance its explanatory power and suggest new treatment strategies.     

Prevention education and substance abuse treatment

Relapse prevention is influenced by a number of variables including stress and negative mood states, motivation and commitment to abstinence, social support, physiological factors, withdrawal symptoms, and a repertoire of cognitive and behavioral strategies utilized in responding to the relapse process. Diverse theoretical approaches have emphasized conditioning models as well as information processing, cognitive and affective components of treatment, cognitive and behavioral coping responses, and a variety of other procedures. Outcome studies related to treatment have failed to consistently support the effectiveness of several of these components. To overcomes this, the authors advocate a single subject design in the study of these approaches. This article emphasizes the role of relapse prevention, and training and education in facilitating long-term abstinence, particularly with those intervention methods that are based on social learning theory and cognitive-behavioral models.     

Effects of tobacco smoking on electroencephalographic, auditory evoked and event related potentials

After overnight abstinence, tobacco smokers smoked an average nicotine yield cigarette and nonsmokers sham smoked an unlit placebo cigarette. EEG alpha(1), delta, and theta frequency amplitudes decreased, whereas alpha(2) and beta frequency amplitude increased. Short, middle (EP) and long latency ERP were also studied in nonsmokers and smokers just after smoking, and after overnight abstinence from tobacco. Short latency potentials were unaffected by tobacco smoking or abstinence. Middle and long-latency potentials were reduced during abstinence and enhanced immediately after tobacco smoking. These findings indicate that compared to nonsmokers smokers have a higher arousal level after smoking than when partially abstinent. Evidence for both normalization from tobacco abstinence as well as stimulation was obtained.     

长期戒断海洛因成瘾者冲动性相关脑区的结构及功能特征

冲动性是药物成瘾者的典型特征, 它既包含了抑制控制成瘾者药物使用的力量, 也包含驱动成瘾者使用药物的成分, 两者不平衡导致冲动性用药行为。海洛因成瘾者本身具有冲动性人格特质, 长时间的海洛因使用又会造成成瘾者冲动性相关的大脑结构与功能的异常。目前难以确定戒断后, 冲动性及相关的大脑结构与功能是否还呈异常状态。本研究采用基于体素的形态学分析、低频振幅、局部一致性和功能连接方法, 以35例海洛因成瘾戒断者和无任何成瘾史的健康个体26人为研究对象, 探索在长期戒断后, 海洛因成瘾者与其冲动性相关的驱动、控制系统脑网络的结构和功能情况。结果显示, 相比对照组, 戒断组灰质总体积及右内侧额上回的灰质体积显著减小, 右侧颞中回和左内侧旁扣带回的灰质体积随用药总量的增加而降低; 右侧眶部额下回与尾状核功能连接显著增强, 右侧颞中回和左侧中央前回功能连接显著降低; 右眶额中回的ReHo值、右眶额下回和左海马体的ALFF值比对照组显著更低, 而右中央后回的ReHo值显著更高。这些脑区的状况与冲动性的神经基础相吻合, 说明海洛因成瘾戒断者在戒断44个月, 奖赏、凸显、习惯性行为等网络系统仍然呈现异常状态, 且与成瘾药物使用总量有关。这些异常可能是成瘾冲动性的驱动力的神经基础, 可以作为解释成瘾者戒断后容易复吸的因素之一。     

Effects of dopamine transporter and receptor polymorphisms on smoking cessation in a bupropion clinical trial.

This study examined the role of dopaminergic genes in prospective smoking cessation and response to bupropion treatment in a placebo-controlled clinical trial. Smokers of European ancestry (N=418) provided blood samples for genetic analysis and received either bupropion or placebo (10 weeks) plus counseling. Assessments included the dopamine D2 receptor (DRD2) genotype, dopamine transporter (SLC6A3) genotype, demographic factors, and nicotine dependence. Smoking status was verified at the end of treatment (EOT) and at 6-month follow-up. The results provided evidence for a significant DRD2 * SLC6A3 interaction effect on prolonged smoking abstinence and time to relapse at EOT, independent of treatment condition. Such effects were no longer significant at 6-month follow-up, however. These results provide the first evidence from a prospective clinical trial that genes that alter dopamine function may influence smoking cessation and relapse during the treatment phase.     

工作记忆训练对药物成瘾者认知功能的改善及其机制

对处于戒断期的各类药物成瘾群体进行认知训练，训练后药物成瘾个体认知能力得到改善，成瘾症状也得到了一定缓解。认知训练能够加速药物成瘾者大脑受损区域的自发性恢复，尤其是使影响个体抑制控制能力的中脑边缘多巴胺系统和前额叶系统发生功能性和结构性的积极变化，实现药物成瘾个体高级认知能力的改善。今后可以从不同类别的药物成瘾是否全部具有可逆性，设置的认知训练任务能否起到改善认知能力的效果，药物成瘾个体训练的性别差异以及训练效果的保持时间等角度进行研究。     

自我扩张模型的研究述评

自我扩张模型提出人们具有自我扩张的动机, 即通过扩张自我来提高自我效能的动机, 它是人类的一个基本动机。自我扩张的一种方式就是将他人纳入自我, 包括他人的资源、观念和认同。该模型是一个概念框架, 为研究与关系相关的心理学现象提供了一个理论平台。它不仅更新了对“相似—吸引效应”、“接触假说”、夫妻关系、群际关系的解释, 对于戒烟等实际活动还具有很大的应用价值。然而, 自我扩张模型本身并未成熟, 在未来的研究中需要进一步完善, 同时也需要结合更多的心理学理论进行探索, 并应用到实践领域中去。     

Using Acceptance and Commitment Therapy During Methadone Dose Reduction: Rationale,Treatment Description,and a Case Report

Many clients who undergo methadone maintenance (MM) treatment for heroin and other opiate dependence prefer abstinence from methadone. Attempts at methadone detoxification are often unsuccessful, however, due to distressing physical as well as psychological symptoms. Outcomes from an MM client who voluntarily participated in an Acceptance and Commitment Therapy (ACT)–based methadone detoxification program are presented. The program consisted of a 1-month stabilization and 5-month gradual methadone dose reduction period, combined with weekly individual ACT sessions. Urine samples were collected twice weekly to assess for use of illicit drugs. The participant successfully completed the program and had favorable drug use outcomes during the course of treatment, and at the 1-month and 1-year follow-ups. Innovative behavior therapies, such as ACT, that focus on acceptance of the inevitable distress associated with opiate withdrawal may improve methadone detoxification outcomes.     

The time course and significance of cannabis withdrawal

Withdrawal symptoms following cessation of heavy cannabis (marijuana) use have been reported, yet their time course and clinical importance have not been established. A 50-day outpatient study assessed 18 marijuana users during a 5-day smoking-as-usual phase followed by a 45-day abstinence phase. Parallel assessment of 12 ex-users was obtained. A withdrawal pattern was observed for aggression, anger, anxiety, decreased appetite, decreased body weight, irritability, restlessness, shakiness, sleep problems, and stomach pain. Onset typically occurred between Days 1-3, peak effects between Days 2-6, and most effects lasted 4-14 days. The magnitude and time course of these effects appeared comparable to tobacco and other withdrawal syndromes. These effects likely contribute to the development of dependence and difficulty stopping use. Criteria for cannabis withdrawal are proposed.     

Effects of time-based administration of abstinence reinforcement targeting opiate and cocaine use

Polydrug use is a common problem among patients in opioid-substitution treatment. Polydrug use has been reduced by administering abstinence-reinforcement contingencies in a sequence, such that a single drug is targeted until abstinence is achieved, and then an additional drug is targeted. The present study examined effects of administering abstinence-reinforcement contingencies sequentially based on time rather than on achieved abstinence. Participants accessed paid work (about $10/hr maximum) in the Therapeutic Workplace by providing urine samples 3 times per week. The urine samples were tested for opiates and cocaine. During an induction period, participants earned maximum pay independent of drug abstinence. Then, maximum pay depended upon urine samples that were negative for opiates. Two weeks later, maximum pay depended upon urine samples that were negative for both opiates and cocaine. Opiate and cocaine abstinence increased following administration of the respective contingencies. The time-based administration of abstinence reinforcement increased opiate and cocaine abstinence.