Individual differences in the attribution of incentive salience to a reward-related cue: Influence on cocaine sensitization (original) (raw)
Related papers
A cocaine cue acts as an incentive stimulus in some but not others: implications for addiction
Biological Psychiatry
BACKGROUND: In addicts drug cues attract attention, elicit approach, and motivate drug-seeking and drug-taking behavior, and addicts find it difficult to resist such cues. In preclinical studies we have found, however, that food cues acquire incentive motivational properties only in a subset of individuals. For example, a food cue becomes attractive, eliciting approach and engagement with it, and acts as an effective conditional reinforcer in some rats but not others. We asked, therefore, whether rats that have a propensity to attribute incentive salience to a food cue are the same ones that attribute incentive value to a drug (cocaine) cue. METHODS: We first used a Pavlovian conditioned approach procedure to determine which individual rats attributed incentive salience to a food cue. A second cue was then associated with the IV self-administration of cocaine. Later, the ability of the cocaine cue to maintain self-administration behavior and to reinstate self-administration after extinction was assessed. RESULTS: We report that in individuals that had a propensity to attribute incentive salience to a food cue, a cocaine cue spurred motivation to take drugs (its removal greatly diminished self-administration) and reinstated robust drug-seeking after extinction. However, in those individuals that failed to attribute incentive salience to a food cue, the cocaine cue was relatively devoid of incentive motivational properties. CONCLUSIONS: We conclude that it is possible to determine, before any drug experience, which individuals will most likely have difficulty resisting drug cues, a trait that might confer susceptibility to addiction.
Individual variation in the motivational properties of cocaine
Neuropsychopharmacology
Cues in the environment associated with drug use draw the attention of addicts, elicit approach, and motivate drug-seeking and drug-taking behavior, making abstinence difficult. However, preclinical studies have identified large individual differences in the extent to which reward cues acquire these incentive motivational properties. For example, only in some rats does a spatially discrete food cue become attractive, eliciting approach and engagement with it, and acts as an effective conditioned reinforcer. Moreover, a discrete cocaine cue also acquires greater motivational control over behavior in rats prone to attribute incentive salience to a food cue. In this study, we asked whether there is similar individual variation in the extent to which interoceptive cues produced by cocaine itself instigate cocaine-seeking behavior. After quantifying individual variation in the propensity to attribute incentive salience to a food cue, rats were trained to self-administer cocaine in the absence of an explicit conditional stimulus. We then assessed motivation for cocaine by: (1) performance on a progressive ratio schedule, and (2) the degree to which a cocaine 'prime' reinstated cocaine-seeking following extinction of self-administration behavior. We found that rats prone to attribute incentive salience to a food cue worked harder for cocaine, and showed more robust cocaine-induced reinstatement. We conclude that there is considerable individual variation in the motivational properties of cocaine itself, and this can be predicted by the propensity to attribute incentive salience to reward cues.
The attribution of incentive salience to a stimulus that signals an intravenous injection of cocaine
Behavioural Brain Research, 2006
A central premise of a number of theories of addiction is that discrete environmental stimuli repeatedly paired with drugs of abuse acquire incentive salience as a result of Pavlovian learning. There is, however, no unequivocal evidence supporting this assumption. Thus, we employed a Pavlovian conditioning procedure known to imbue non-drug reinforcers with incentive salience and extended it to study the effects of intravenous cocaine. Specifically, we examined whether a cue paired with intravenous cocaine administration would come to elicit approach towards it (sign-tracking), even if no behavioral response were required to receive the cue or drug. We found that when a cue was paired with intravenous cocaine delivery (but not when it was unpaired) rats came to approach and investigate the cue, and did so with increasing rapidity. We conclude that Pavlovian learning can imbue drug-paired cues with incentive salience, making them attractive and "wanted" stimuli. Delineating the neurobiological mechanisms responsible for this process will be important for understanding and treating drug addiction.
Extended cocaine-seeking produces a shift from goal-directed to habitual responding in rats
Physiology & Behavior, 2016
Cocaine addiction is often characterized by a rigid pattern of behavior in which cocaine users continue seeking and taking drug despite negative consequences associated with its use. As such, full acquisition and relapse of drug-seeking behavior may be attributed to a shift away from goaldirected responding and a shift towards the maladaptive formation of rigid and habit-like responses. This rigid nature of habitual responding can be developed with extended training and is typically characterized by insensitivity to changes in outcome value. The present study determined whether cocaine (primary reinforcer) and cocaine associated cues (secondary reinforcer) could be devalued in rats with different histories of cocaine self-administration. Specifically, rats were trained on two schedules of cocaine self-administration (long-access vs. short-access). Following training the cocaine reinforcer was devalued through three separate pairings of lithium chloride with cocaine infusions. Cocaine history did not have an impact on devaluation of cocaineassociated cues. However, the reinforcing properties of cocaine were devalued only in rats on a short-access cocaine schedule but not those trained on a long-access schedule. Taken together this pattern of findings suggests that, in short access rats, devaluation is specific to the primary reinforcer and not associative stimuli such as cues. Importantly, rats that received extended training during self-administration displayed insensitivity to outcome devaluation of the primary reinforcer as well as all associative stimuli, thus displaying rigid behavioral responding similar to behavioral patterns found in addiction. Alternatively, long access cocaine exposure may have altered the devaluation threshold.
The psychology and neurobiology of addiction: an incentive–sensitization view
Addiction, 2000
The question of addiction speci cally concerns (1), the process by which drug-taking behavior, in certain individuals, evolves into compulsive patterns of drug-seeking and drug-taking behavior that take place at the expense of most other activities and (2), the inability to cease drug-taking; the problem of relapse. In this paper current biopsychological views of addiction are critically evaluated in light of the "incentivesensitization theory of addiction", which we rst proposed in 1993, and new developments in research are incorporated. We argue that traditional negative reinforcement, positive reinforcement, and hedonic accounts of addiction are neither necessary nor suf cient to account for compulsive patterns of drug-seeking and drug-taking behavior. Four major tenets of the incentive-sensitization view are discussed. These are:
Enduring Resistance to Extinction of Cocaine-Seeking Behavior Induced by Drug-Related Cues
Neuropsychopharmacology, 2001
The conditioning of cocaine's pharmacological actions with environmental stimuli is thought to be a critical factor in long-lasting relapse risk associated with cocaine addiction. To study the significance of environmental stimuli in enduring vulnerability to relapse, the resistance to extinction of drug-seeking behavior elicited by a cocainerelated stimulus was examined. Male Wistar rats were trained to associate discriminative stimuli (S D ) with the availability of intravenous cocaine (S ϩ ) vs. the availability of non-rewarding (S Ϫ ) saline solution, and then placed on extinction conditions during which intravenous solutions and S D were withheld. The rats were then presented with the S ϩ or S Ϫ alone in 60-min reinstatement sessions conducted at 3-day intervals. To examine the long-term persistence of the motivating effects of the cocaine S ϩ , a subgroup of rats was re-tested following an additional three months of abstinence during which time the rats remained confined to their home cages. Re-exposure to the cocaine S ϩ selectively elicited robust responding at the previously active lever. The efficacy and selectivity of this stimulus to elicit responding remained unaltered throughout a 34-day phase of repeated testing as well as following the additional extended abstinence period. In pharmacological tests, conducted in a separate group of rats, the dopamine (DA) D 1 antagonist SCH 39166 (10 g/kg), the D 2/3 antagonist nafadotride (1 mg/kg), and the D 2/3 agonist PD 128907 (0.3 mg/kg) suppressed the cue-induced response reinstatement while the D 1 agonist SKF 81297 (1.0 mg/kg) produced a variable behavioral profile attenuating cue-induced responding in some rats while exacerbating this behavior in others. The results suggest that the motivating effects of cocaine-related stimuli are highly resistant to extinction. The undiminished efficacy of the cocaine S ϩ to induce drug-seeking behavior both with repeated testing and following long-term abstinence parallels the long-lasting nature of conditioned cue reactivity and cue-induced cocaine craving in humans, and confirms a significant role of learning factors in long-lasting vulnerability to relapse associated with cocaine addiction. Finally, the results support a role of DA neurotransmission in cue-induced cocaine-seeking behavior.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 2015
Drug addiction is associated with a relative devaluation of natural or socially-valued reinforcers that are unable to divert addicts from seeking and consuming the drug. Before protracted drug exposure, most rats prefer natural rewards, such as saccharin, over cocaine. However, a subpopulation of animals prefer cocaine over natural rewards and are thought to be vulnerable to addiction. Specific behavioral traits have been associated with different dimensions of drug addiction. For example, anxiety predicts loss of control over drug intake whereas sensation seeking and sign-tracking are markers of a greater sensitivity to the rewarding properties of the drug. However, how these behavioral traits predict the disinterest for natural reinforcers remains unknown. In a population of rats, we identified sensation seekers (HR) on the basis of elevated novelty-induced locomotor reactivity, high anxious rats (HA) based on the propensity to avoid open arms in an elevated-plus maze and sign-tra...
Incentive-Sensitization Theory of Addiction: Implications for Research and Treatment
There have been many theories of addiction; early models pointed to moral failings as the reason for alcohol and substance abuse. The disease model was the first step toward consideration of an underlying biological reason for the symptoms of addiction. Advances in neuroimaging technology has enabled visualization of components of the reward pathway in the brain and the role of neuroadaptation in substance use disorders. The incentive-sensitization theory (IST) is a complex hypothesis that explores the neuroadaptations that may result from substance use, examines changes to the neurocircuitry and neurochemistry, and accounts for learning, behavioral, and motivational reasons of addiction. One factor of addiction which has puzzled researchers for many years is the phenomenon of relapse after long periods of abstinence. IST suggests an underlying biological basis for “cravings” that may lead to increased usage and relapse. This paper examines just a few of the numerous studies that have been completed to test the major tenets of IST, with many providing at least partial support for the theory including the concepts of incentive salience, drug wanting and drug liking.