Rationale and objective Empirical studies indicate that nicotine enhances some aspects of attention and cognition, suggesting a role in the maintenance of tobacco dependence. The purpose of this review was to update the literature since our previous review (Heishman et al. Exp Clin Psychopharmacol 2:345–395, 1994) and to determine which aspects of human performance were most sensitive to the effects of nicotine and smoking. Methods We conducted a meta-analysis on the outcome measures of 41 double-blind, placebo-controlled laboratory studies published from 1994 to 2008. In all studies, nicotine was administered, and performance was assessed in healthy adult nonsmokers or smokers who were not tobacco-deprived or minimally deprived (≤2 h). Results There were sufficient effect size data to conduct meta-analyses on nine performance domains, including motor abilities, alerting and orienting attention, and episodic and working memory. We found significant positive effects of nicotine or smoking on six domains: fine motor, alerting attention-accuracy and response time (RT), orienting attention-RT, short-term episodic memory-accuracy, and working memory-RT (effect size range=0.16 to 0.44). Conclusions The significant effects of nicotine on motor abilities, attention, and memory likely represent true performance enhancement because they are not confounded by withdrawal relief. The beneficial cognitive effects of nicotine have implications for initiation of smoking and maintenance of tobacco dependence.

No abstract

The questionnaire yielded a coherent factor structure; women smoked more for tension reduction/relaxation, stimulation and for social reasons than men; addictive smoking and automatic smoking behaviour were similar in both sexes and were associated strongly with a high level of nicotine dependence; the 'habit/automatism' score predicted failure to quit over and above cigarettes per day.

Background The Marijuana Craving Questionnaire (MCQ) is a valid and reliable, 47-item self-report instrument that assesses marijuana craving along four dimensions: compulsivity, emotionality, expectancy, and purposefulness. For use in research and clinical settings, we constructed a 12-item version of the MCQ by selecting three items from each of the four factors that exhibited the greatest within-factor internal consistency (Cronbach's alpha coefficient). Methods Adult marijuana users (n = 490), who had made at least one serious attempt to quit marijuana use but were not seeking treatment, completed the MCQ-Short Form (MCQ-SF) in a single session. Results Confirmatory factor analysis of the MCQ-SF indicated good fit with the 4-factor MCQ model, and the coefficient of congruence indicated moderate similarity in factor patterns and loadings between the MCQ and MCQ-SF. Homogeneity (unidimensionality and internal consistency) of MCQ-SF factors was also consistent with reliability values obtained in the initial validation of the MCQ. Conclusions Findings of psychometric fidelity indicate that the MCQ-SF is a reliable and valid measure of the same multidimensional aspects of marijuana craving as the MCQ in marijuana users not seeking treatment.

Findings suggested that four specific constructs characterize craving for marijuana: (1) compulsivity, an inability to control marijuana use; (2) emotionality, use of marijuana in anticipation of relief from withdrawal or negative mood; (3) expectancy, anticipation of positive outcomes from smoking marijuana; and (4) purposefulness, intention and planning to use marijuana for positive outcomes. These data indicate that the MCQ is a valid and reliable instrument for assessing marijuana craving in individuals not seeking drug abuse treatment and that marijuana craving can be measured in the absence of withdrawal.