Cue reactivity

Learned response to drug related stimuli in addiction

Cue reactivity is a type of learned response which is observed in individuals with an addiction and involves significant physiological and psychological reactions to presentations of drug related stimuli (i. e., drug cues). The central tenet of cue reactivity is that cues previously predicting receipt of drug reward under certain conditions can evoke stimulus associated responses such as urges to use drugs. In other words, learned cues can signal drug reward, in that cues previously associated with drug use can elicit cue reactivity such as arousal, anticipation, and changes in behavioral motivation. Additionally, cue reactivity allows for the development of testable hypotheses grounded in established theories of human behavior.

Drummond (2000) identified a preliminary classification of cue types including four main categories: (1) Exteroceptive; (2) Interceptive; (3) Temporal; and (4) Cue relationship. In other words, after systematic association of exteroceptive or interoceptive cues (i. e., conditioned stimuli) with drug administration (i. e., unconditioned stimuli), the cues will reliably signal administration and drug effects. When cues predict administration, they acquire the ability to elicit physiological and psychological responses (i. e., cue reactivity/ conditioned response) which increase the likelihood of substance use. The three models differ in the nature of the reaction that is elicited. For instance, during a drinking episode and individual with an alcohol use disorder is exposed to cues (e. g., sight and smell of preferred beverage containing alcohol) at a point when their blood alcohol level is falling (i. e., unconditioned stimuli), such as the morning after a heavy drinking episode. In other words, the conditioned response resembles the unconditioned effect of the substance. Each conditioning model is empirically supported.

Although most theories of substance dependence acknowledge the role of conditioning and view this research as invaluable, not all theories assume that conditioning is sufficient in explaining this phenomena as cue reactivity appears to be complex and highly individual. Pertaining to substance factors, latency since last use is an important factor to consider. However, research focused on these substances have been primarily done in isolation of each other and there are nuances regarding cue reactivity within each substance. The cues that elicit the greatest reactivity among those with an alcohol use disorder are the ingestion of a small amount of alcohol or expectancy of alcohol availability. Regarding opiates, auditory, visual, or role play of drug sales appear to be the most influential cues. Even after extended periods of abstinence (i. e., years) cues are reported as preceding relapse. The authors concluded that it is suggested that reactivity to smoking cues plays a role in smoking relapse. Findings showed that greater visual alcohol cue elicited activation of the dorsomedial prefrontal cortex (dmPFC) predicted resuming alcohol consumption following discharge. Given the theoretical conceptualization of the influence of cue reactivity on relapse, it could be understood that greater cue induced craving in the laboratory should predict risk for relapse in the real world when similar cues are encountered in the natural environment. Therefore, psychotherapy and pharmacotherapy that blunts cue reactivity in the laboratory should be a marker of treatment efficacy in the real world.

Cue reactivity is typically studied in a laboratory paradigm. First, participants complete a battery of baseline measures including psychological and physiological assessments (pre exposure measurements). Second, participants are exposed to either a neutral or substance related cue. Third, psychological and physiological measurements are repeated (post exposure measurements). A variety of cue presentations are utilized in this procedure, such as in vivo (e. g., sitting in front of a preferred substance like a bottle of beer), imaginal (e. g., vividly imagining situations related to drug use), audio (e. g., listening to a recording of someone describing substance use), pictorial (e. g., viewing pictures of substance use), and virtual reality. These cue presentations can also be in combination. For instance, the participant is interacting (smelling, seeing) with a preferred alcohol drink while listening to a recording recounting past substance use. It is recommended that researchers use both drug related and neutral control cues (e. g., pencil, glass of water) rather than drug related cues to pre exposure baseline measures. The cue reactivity paradigm is a frequently used method within the addictions field because it allows for testing hypotheses regarding the additions process in a controlled laboratory setting and is grounded in theory. Researchers have made efforts to make the cue reactivity paradigm more ecologically valid by having participants take digital pictures of their environments. For instance, Miranda and colleagues (2014) tested the effects of naltrexone, an opiate receptor antagonist, on adolescent alcohol cue reactivity. The study found that naltrexone blunted alcohol cue elicited craving in the laboratory and natural environment. Regarding psychotherapy, assessing cue reactivity has provided insight into potential relapse triggers and cue exposure has been used as a treatment approach. Given that substance related cues can promote substance use, common treatment strategies in cognitive behavioral therapy are to assist patients in identifying cues and developing strategies to avoid avoidable cues. In cue exposure treatment, patients are exposed to personally relevant substance cues through in vivo and imaginal exposures.