Drugs as instruments: a new framework for non-addictive psychoactive drug use

Most people who are regular consumers of psychoactive drugs are not drug addicts, nor will they ever become addicts. In neurobiological theories, non-addictive drug consumption is acknowledged only as a "necessary" prerequisite for addiction, but not as a stable and widespread behavior in its own right. This target article proposes a new neurobiological framework theory for non-addictive psychoactive drug consumption, introducing the concept of "drug instrumentalization." Psychoactive drugs are consumed for their effects on mental states. Humans are able to learn that mental states can be changed on purpose by drugs, in order to facilitate other, non-drug-related behaviors. We discuss specific "instrumentalization goals" and outline neurobiological mechanisms of how major classes of psychoactive drugs change mental states and serve non-drug-related behaviors. We argue that drug instrumentalization behavior may provide a functional adaptation to modern environments based on a historical selection for learning mechanisms that allow the dynamic modification of consummatory behavior. It is assumed that in order to effectively instrumentalize psychoactive drugs, the establishment of and retrieval from a drug memory is required. Here, we propose a new classification of different drug memory subtypes and discuss how they interact during drug instrumentalization learning and retrieval. Understanding the everyday utility and the learning mechanisms of non-addictive psychotropic drug use may help to prevent abuse and the transition to drug addiction in the future.     

Non-addictive psychoactive drug use: Implications for behavioral addiction

The newly proposed framework for non-addictive psychoactive substances postulated by Müller & Schumann (M&S) provides an interesting and plausible explanation for non-addictive drug use. However, with specific reference to the relevant behavioral addiction literature, this commentary argues that the model may unexpectedly hold utility not only for non-addictive use of drugs, but also for non-addictive use of other potentially addictive behaviors.     

Dissemination of psychoactive substance information by innovative drug users.

Internet-based drug information may be relayed by innovative drug users, a group of individuals who use the web to learn about a new drug, experiment with that substance, and then disseminate their knowledge and experiences to others. We investigated the mechanisms adopted by innovative drug-using adolescents to distribute Internet drug information and experiences to peers, the size and geographic distribution of the receiving group, and the age at which innovative drug users began to disseminate drug information. Method: Cross-sectional survey of adolescents recruited by a respondent-driven sampling method. Of 18 innovative drug users, 17 reported using instant messaging (IM) to disseminate drug information and experiences to peers. The average age at which respondents adopted IM for this purpose was 16 years. Fifteen of 17 described using a distribution list with as many as 200 individuals who received only drug information. Ten respondents instant messaged drug information to online peers greater than 250 miles distant; nine respondents attached links to online drug resources (including www.erowid.org). This study has identified that IM plays an important role in the dissemination of Internet-based drug information by individual innovative drug users into larger social networks. Pediatricians should consider assessing IM use in drug abuse evaluations and recommending that parents of children with drug abuse problems should consider suspending IM services as a means of truncating the delivery of reinforcing drug information.     

Modification of the punishing effects of psychoactive drugs in rats by previous drug experience.

In Experiment 1, it was shown that chronic prior exposure to amphetamine attenuated the conditioned avoidance of saccharin that was produced by both amphetamine and morphine during gustatory conditioning trials; the relationship between morphine and amphetamine was somewhat anomalous because of their pharmacological dissimilarity. The relationship was also asymmetrical, since in Experiment 2, chronic prior exposure to morphine failed to mitigate avoidance conditioning by amphetamine but was effective in attenuating conditioning by morphine itself. In a third experiment, it was found that prior treatment with chlordiazepoxide attenuated saccharin avoidance conditioned by chlordiazepoxide but not by amphetamine or morphine. The findings were related to Parker, Failor, and Weidman's hypothesis, based on findings with morphine, concerning the development of conditioned preferences for substances associated with the repletion of artificially induced biological needs. It was suggested that the findings were best interpreted as a reflection of drug tolerance rather than conditioned preference.     

Nicotine trained as a negative feature passes the retardation-of-acquisition and summation tests of a conditioned inhibitor

Nicotine functions as a negative feature in a Pavlovian discriminated goal-tracking task. Whether withholding of responding to the conditional stimulus (CS) reflects nicotine functioning as a conditioned inhibitor is unknown. Accordingly, the present research sought to determine whether nicotine trained as a negative feature passed the retardation-of-acquisition and summation tests, thus characterizing it as a pharmacological (interoceptive) conditioned inhibitor. In the retardation test, rats received either nicotine (0.4 mg/kg) or chlordiazepoxide (5 mg/kg) negative feature training in which the drug state signaled when a 15-sec light CS would not be paired with sucrose; light was paired with sucrose on intermixed saline sessions. Following acquisition of the discrimination, both groups received nicotine CS training in which sucrose was intermittently available on nicotine but not intermixed saline sessions. Acquisition of conditioned responding to the nicotine CS was slower in the nicotine negative feature group than in the chlordiazepoxide negative feature group. In the summation test, rats were assigned to either the nicotine negative feature group or a pseudoconditioning control. In this control, the light CS was paired with sucrose on half the nicotine and half the saline sessions. Both groups also received excitatory training in which a white noise CS was paired with sucrose. The summation test consisted of presenting the white noise in conjunction with nicotine. Conditioned responding evoked by the white noise was decreased in the negative feature but not the pseudoconditioning group. Combined, the results provide the first evidence that an interoceptive stimulus (nicotine) can become a conditioned inhibitor.     

To use or not to use: Expanding the view on non-addictive psychoactive drug consumption and its implications

Proposing a change to the view on psychoactive drug use in non-addicts touches a sensitive issue because of its potential implications to addiction prevention, therapeutic practice, and drug policy. Commentators raised nine questions that ranged from clarifications, suggested extensions of the model to supporting data previously not regarded, to assumptions on the implications of the model. Here, we take up the suggestions of the commentators to expand the model to behavioral addictions, discuss additional instrumentalization goals, and review the evidence from laboratory animal studies on drug instrumentalization. We consider further the role of sociocultural factors and individual development in the establishment in drug instrumentalization and addiction. Finally, we clarify which implications we think this model may have. We conclude that drug instrumentalization theory can be further applied to other behaviors but will require a sensitive debate when used for drug and addiction policy that directly affects prevention and treatment.     

Money as tool, money as drug: the biological psychology of a strong incentive

Why are people interested in money? Specifically, what could be the biological basis for the extraordinary incentive and reinforcing power of money, which seems to be unique to the human species? We identify two ways in which a commodity which is of no biological significance in itself can become a strong motivator. The first is if it is used as a tool, and by a metaphorical extension this is often applied to money: it is used instrumentally, in order to obtain biologically relevant incentives. Second, substances can be strong motivators because they imitate the action of natural incentives but do not produce the fitness gains for which those incentives are instinctively sought. The classic examples of this process are psychoactive drugs, but we argue that the drug concept can also be extended metaphorically to provide an account of money motivation. From a review of theoretical and empirical literature about money, we conclude that (i) there are a number of phenomena that cannot be accounted for by a pure Tool Theory of money motivation; (ii) supplementing Tool Theory with a Drug Theory enables the anomalous phenomena to be explained; and (iii) the human instincts that, according to a Drug Theory, money parasitizes include trading (derived from reciprocal altruism) and object play.     

尼古丁作用的辩证思考

尼古丁是一种液态生物碱 ,无色易挥发 ,溶于水 ,并易形成可溶性盐。它作为烟草中的主要毒性物质 ,在吸烟引起的许多疾病中起到了重要作用 ,在医学领域 ,这方面的研究已相当广泛和深入。但近几年来随着对尼古丁药用价值的探讨发现 ,其对许多疾病有缓解和潜在的治疗作用。本文就尼古丁致病和治病效应的两个方面作一综述。1　尼古丁的致病作用1.1　慢性阻塞性疾病 ,动脉粥样硬化等慢性炎症疾病尼古丁促进中性粒细胞 (PMNs)浸润、活化 ,释放炎性介质溶酶体酶、花生四烯酸及活性氧 ,作用于弹性蛋白、胶原蛋白 ,引起损伤。收集大鼠腹腔内PMNs ,…     

Nicotine and familial vulnerability to schizophrenia: a discordant twin study

Tobacco use is significantly associated with schizophrenia. However, it is not clear if smoking is associated with the illness itself, treatment, or underlying vulnerability to the disease. Smoking was studied in a sample of schizophrenic probands (n = 24), their unaffected co-twins (n = 24), and controls (n = 3,347). Unaffected co-twins had higher rates of daily smoking than controls. Probands and co-twins were more frequently unsuccessful in attempts to quit than controls. Probands reported shaky hands and depression following smoking cessation more often than controls, whereas unaffected co-twins reported difficulty concentrating, drowsiness, nervousness, and headache following smoking cessation more often than controls. Results are consistent with the hypothesis that nicotine use is influenced by familial vulnerability to schizophrenia, not just clinical schizophrenia per se.     

Ego functioning and acute adverse reactions to psychoactive drugs.

The relationship between ego functioning and acute adverse reactions to psychoactive drugs was examined using retrospective data. The data were consistent with a causal model in which characteristic use of regression (and to a lesser extent repression) was associated with acute adverse reactions to marijuana and to LSD. Regression also had an indirect effect through increased usage of LSD. Subjects characterized by the use of intellectualization and denial were less likely to report developing acute adverse reactions. A higher score on a general measure of coping was related to avoiding acute adverse reactions to LSD, but not to marijuana. Projection, regression in the service of the ego, and tolerance of ambiguity has no effect on acute adverse reactions.     

Neighborhood social disorder as a determinant of drug injection behaviors: a structural equation modeling approach.

Neighborhood environments are increasingly recognized as a contextual determinant of health, behaviors, and disease; however, the pathways through which neighborhood characteristics impact health behaviors are poorly understood. This article examines pathways to elucidate how neighborhood social disorder may lead to HIV transmission. Data are from a baseline survey of 701 injection drug users from the Self-Help in Eliminating Lethal Diseases Study, an HIV prevention intervention in Baltimore. Structural equation modeling was used to examine the pathways among social disorder, psychological distress, and drug injection behaviors. The relationship between disorder and injection behaviors in the models tested suggests that psychological distress is higher in more socially disordered neighborhoods, that distress leads to greater injection frequency and equipment sharing, and that injection frequency predicts equipment sharing.     

Perceived fairness of employee drug testing as a predictor of employee attitudes and job performance

Although management of drug testing programs is becoming a critical organizational issue, no systematic conceptual framework has been applied to the study of employee reactions to drug testing. In this study an organizational justice framework was used to explain and predict the relationships among two types of justice (procedural justice and outcome fairness) employee attitudes (job satisfaction, commitment, and management trust), and behavior (turnover intentions and performance). Survey data from 195 employees in a pathology laboratory indicated that justice predicts employee attitudes and performance. Specifically, procedural justice, but not outcome fairness, predicted all 5 criterion variables. These results demonstrate the importance of procedural justice perceptions for predicting employee reactions to drug testing programs.     

Self-administration cues as signals: drug self-administration and tolerance

There is evidence that drug-associated exteroceptive cues elicit compensatory conditional responses (CCRs) that contribute to tolerance. The authors evaluated whether interoceptive, self-administration cues (SACs) similarly contribute to tolerance. In Experiments 1 and 2, the ataxic effect of ethanol was measured in rats that self-administered (SA) ethanol--by either oral consumption or intragastric infusion--and in rats that were yoked (Y) to these self-administrators. In both experiments, the ataxic effect of ethanol was more pronounced in Y than in SA rats. In addition, SA rats failed to display usual levels of tolerance when ethanol was administered in the absence of SACs and displayed a CCR of hypertaxia in response to SACs not followed by ethanol. The results of Experiment 3 indicate that the ataxic effect of intravenous heroin also was greater in Y than in SA rats. The findings suggest that SACs contribute to drug tolerance.     

Caffeine as a performance-enhancing drug in rats: sex, dose, housing, and task considerations

Past animal studies of the performance-enhancing properties of stimulant drugs, such as caffeine, may have suffered from a number of procedural and ethical problems. For example. the housing condition of the animals was often not taken into consideration. As well, endurance tests, such as the forced swim task, sometimes involved ethically (and procedurally) questionable interference with natural swimming behaviour. Some of the manipulations, such as attaching a weight to the swimming animal's tail to increase the difficulty of the task and using mortality as a dependent variable, seem grotesque, even unnecessary. In this experiment, the performance-enhancing effects of caffeine in a modified forced swim task and a dominance task were evaluated using male and female rats as subjects (N=60), housed in either enriched or isolated environments. Analysis indicated that rats respond to caffeine as an interactive function of sex, housing, dose, and task characteristics. It was concluded that performance-enhancing properties of stimulant drugs may be the result of a complex interplay of variables, making simple generalizations questionable.