Self-reports of interoceptive responses during stress and drug cue-related experiences in cocaine- and alcohol-dependent individuals

Characterizing alcohol cue reactive and non-reactive individuals with alcohol use disorder

PURPOSE

Exposure to alcohol-related cues is thought to elicit a conditional response characterized by increased craving in individuals with alcohol use disorder (AUD). In the context of AUD research, it is important to consider that not all individuals with an AUD are alcohol cue reactive. This study systematically examined subjective alcohol cue reactivity and its clinical and drinking correlates in individuals with an AUD enrolled in a human laboratory pharmacotherapy trial.

METHODS

Individuals with current moderate-to-severe AUD (N = 52) completed a standard alcohol cue exposure paradigm and individual difference assessments as part of a human laboratory pharmacotherapy trial (NCT04249882). We classified participants as cue reactive (CR+) and cue non-reactive (CR-), as indicated by self-reported, subjective alcohol urge, and examined group differences in baseline clinical characteristics and drinking outcomes over the course of the trial.

RESULTS

Twenty participants (38%) were identified as CR+, while 32 participants (62%) were identified as CR-. The CR+ and CR- groups did not differ in baseline drinking and AUD clinical characteristics, but the groups differed in race composition (p = 0.02) and smoking prevalence (p = 0.04) such that the CR+ group had lower prevalence of smokers. The CR+, compared with the CR-, group drank more during the trial titration period (p = 0.03). Both groups reduced drinking across the trial (p's < 0.001), but the CR+ group exhibited a smaller reduction in drinking, compared with the CR- group (time x group, p = 0.029; CR-, p < 0.0001; CR+: p = 0.01).

CONCLUSION

Results indicate that cue reactivity is a heterogenous construct. Recognizing this heterogeneity, and the clinical factors associated with it, is critical to advancing this paradigm as an early efficacy marker in AUD research.

Infralow neurofeedback in the treatment of substance use disorders: a randomized controlled trial

BACKGROUND

Infralow neurofeedback (ILF-NF) was recently developed as a subtype of traditional, frequency-based neurofeedback that targets cerebral rhythmic activity below 0.5 Hz and improves brain self-regulation. The efficacy of ILF-NF in the treatment of substance use disorder has not yet been evaluated, but clinical evidence suggests that it may prevent relapse by improving functioning in various life domains. The current study aimed to fill this research gap and extend empirical evidence related to this issue.

METHODS

Ninety-three patients with substance use disorders at an outpatient unit in Norway were randomized to receive 20 sessions (30 minutes each) of ILF-NF training combined with treatment as usual (TAU), or TAU alone. The primary outcome was quality of life post-treatment as an overall measure of functioning. We analyzed between-group differences using Student t tests.

RESULTS

We found no significant differences in quality of life between groups. We found similar nonsignificant results for most of the secondary outcome measures, including drug use, sleep, anxiety and depression. Compared to TAU, the ILF-NF + TAU group reported significantly lower restlessness scores post-treatment (mean difference -1.8, 95 % confidence interval -3.1 to -0.5; p = 0.006).Limitations: This study was limited by broad inclusion criteria and a lack of placebo control (sham neurofeedback treatment).

CONCLUSION

ILF-NF offered limited additional benefit when combined with TAU, except in the area of restlessness. Future studies could further investigate the relationship between ILF-NF, restlessness and substance use in targeted subpopulations to illuminate relapse mechanisms.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT03356210.

Where is emotional feeling felt in the body? An integrative review

Contemporary research on "embodied emotion" emphasizes the role of the body in emotional feeling. The evidence base on interoception, arguably the most prominent strand of embodied emotion research, places emphasis on the cardiac, respiratory and gastrointestinal systems. In turn, interoception has evidence-based links with improved emotion regulation. Despite the focus on separate bodily systems, it is unclear whether particular interoceptive locations play a greater role in emotional feeling and emotion regulation. Further, according to Gross' "process model", the sooner that regulation of an emotion occurs, the better; hence, it is additionally important to identify the first body areas to activate. These issues are investigated in a two-stage integrative review. The first stage was preliminary, giving an overview of the evidence base to highlight the distribution of measured body areas. This indicated that 86% of publications (n = 88) measured cardiac activity, 26% measured the respiratory system, and six percent the gastrointestinal system. Given the emphasis placed on all three systems in interoception theory and research on emotion, this suggests a dearth of comprehensive findings pertaining to feeling locations. The second stage investigated the core issues of where emotional feelings are felt in the body and time-related implications for regulation. This was based on ten texts, which together suggested that the head, throat and chest are the most consistently detected locations across and within numerous emotional contexts. Caution is required, however, since-among other reasons discussed-measurement was not time-restricted in these latter publications, and direct physiological measurement was found in only a minority of cases.

Sleep moderates the relationship between stress and craving in individuals with opioid use disorder

Opioid use disorder (OUD) is a national public health concern. Craving, stress, and exposure to conditioned drug cues are implicated in risk of relapse to opioids. Although impaired sleep has been implicated in risk of relapse to other substances of misuse, little research to date has examined the relationship between sleep and craving in individuals with OUD. The present study examined sleep as a moderator of the relationship between craving and stress in a randomized controlled human laboratory study. Individuals with current OUD (N = 39) completed a 1-night hospital stay to control for factors that may affect craving, stress, and sleep. Sleep was monitored via an actigraphy watch and the Pittsburgh Sleep Quality Index. The next morning, participants were randomized to a 15-min laboratory stress task or a no-stress condition. All participants were then exposed to a 15-min opioid cue paradigm, and craving was measured via self-report. Moderation models were conducted to evaluate whether the sleep indices moderated the relationship between stress condition (independent variable) and craving (dependent variable). Average self-reported nightly sleep duration moderated the relationship between stress condition and craving for participants in the no-stress condition (b = 0.95, p < .05). Specifically, participants in the no-stress condition with lower average nightly sleep duration exhibited significantly greater craving following the opioid cue paradigm. Although preliminary, the findings add to the literature on craving, stress, and sleep among individuals with OUD. Sleep impairment may be an important target of a comprehensive, long-term treatment plan for some patients with OUD. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Interoceptive signaling in alcohol cognitive biases: Role of family history and alliesthetic components

The role of interoceptive signals in the development of cognitive biases for drug-related cues has been hypothesized in the past; however, experimental evidence is lacking. This report examined the relationship between physiological responses and memories for alcohol cues. Participants (n = 158) were categorized as having either a positive or negative family history of alcohol use disorder (AUD). They were assigned to an alcohol, placebo, or control beverage condition to which they were blinded. All participants were presented with alcohol, neutral, and emotional cues. Heart rate variability (HRV) at 0.1 Hz, as an index of viscero-afferent reactivity, and in the high-frequency range was measured during picture-cue exposure. Participants then completed free recall and repetition priming tasks to assess memories for previously presented stimuli. Participants with a positive family history (FHP) for AUD who received an alcohol beverage displayed a positive relationship between 0.1 Hz HRV and free recall. This effect was specific to alcohol cues, highlighting the relevance of physiological signals in the development of alcohol cognitive biases. These results support the hypothesis of a coordinated brain-body interaction in the development of drug-related behaviors. FHP as an AUD risk factor may increase the mapping of physiological responses onto cognitive biases for alcohol cues. Increased ratings of subjective intoxication dampened this relationship, suggesting that perceived bodily states may modulate incentive salience processes. This report provides novel evidence for the involvement of interoceptive signals in addictive processes, setting a precedent for the exploration of brain-body interactions in the study of alcohol cognitive biases.

Functional evaluation of NK1 antagonism on cue reactivity in opiate dependence; An fMRI study

BACKGROUND

Opiate addiction is a major health challenge with substantial societal cost. Though harm minimisation strategies have been effective, there is a growing need for new treatments for detoxification and relapse prevention. Preclinical research has found neurokinin 1 (NK1) receptors have prominent effects on opiate reward and reinforcement, and human studies have found NK1 antagonism led to reductions in craving and withdrawal. However, its effect on brain mechanisms in opiate addiction has not yet been examined.

METHODS

This study aims to assess the impact of NK1 antagonist aprepitant on heroin cue-elicited changes in blood-oxygenation level dependent (BOLD) signal in opiate dependent individuals undergoing detoxification. Participants will attend two scanning sessions and receive a single dose of aprepitant (320 mg) and a placebo in a randomised, cross-over design. During functional magnetic resonance imaging participants will undergo two runs of a cue reactivity task, which consists of passive viewing of drug cues or neutral cues in a block design fashion. We hypothesise that NK1 antagonism will attenuate the BOLD response to drug cues in the caudate nucleus and amygdala. Regions of interest were selected based on NK1 receptor density and their role in cue reactivity and craving.

Interoceptive attention in opioid and stimulant use disorder

Blunted anterior insula activation during interoceptive perturbations has been associated with stimulant (cocaine and amphetamine) use disorder (SUD) and is related to risk for and prognosis of SUD. However, little is known whether these interoceptive alterations extend to opioid use disorder (OUD). This exploratory study used the same experimental probe during functional magnetic resonance imaging (fMRI) to test the hypothesis that SUD and OUD exhibit interoceptive discrepancies characterized by subjective ratings and activation within the insula. Recently, abstinent individuals diagnosed with current SUD (n = 40) or current OUD (n = 20) were compared with healthy individuals (CTL; n = 30) on brain and self-report responses during an interoceptive attention task known to elicit insula activation. Participants selectively attended to interoceptive (heartbeat and stomach) and exteroceptive signals during blood-oxygen-level-dependent fMRI recording. Groups and conditions were compared on (a) activation within probabilistic cytoarchitectonic segmentations of the insula and (b) self-reported stimulus intensity. First, SUD showed amplified ratings of heart-related sensations but attenuation of dorsal dysgranular insula activity relative to CTL. Amplified ratings were linked to drug use recency, while attenuation was normalized with greater past-year stimulant use. Second, SUD and OUD showed attenuation of dorsal dysgranular insula activity during attention to stomach sensations relative to CTL. Taken together, these results are consistent with altered neural processing of interoceptive signals in drug addiction, particularly as a function of SUD. Future studies will need to determine whether interoceptive metrics help to explain substance use disorder pathophysiology and are useful for predicting outcomes.

Evaluating alcohol demand, craving, and depressive symptoms among women in alcohol treatment

BACKGROUND

Depression and alcohol craving predict drinking and relapse rates among alcohol treatment seekers. Alcohol demand, or one's valuation of alcohol may be another determinant of drinking. There is little known about alcohol demand and its association with depression, craving, and drinking among treatment-seeking adults.

METHOD

Participants were 71 women with elevated depressive symptoms seeking outpatient treatment for alcohol use disorder (AUD). At baseline, participants self-reported daily drinking amount, alcohol craving, depressive symptoms, and alcohol demand assessed with the alcohol purchase task (APT; a task requesting participants to make hypothetical purchases of drinks at escalating prices). Baseline associations among alcohol demand, depressive symptoms, alcohol craving, and drinking severity were assessed.

RESULTS

Participants averaged 40.68 (SD = 11.78) years of age, consumed 8.84 (SD = 5.14) drinks per drinking day and reported 15.45 (SD = 7.51) heavy drinking days in the past 30 days, and had an average PHQ-9 depression score of 13.00 (SD = 4.28). Results suggest that the alcohol demand metrics of intensity (consumption level when drinks are free) and O_max (maximum expenditure on alcohol) were associated with drinks per drinking day, whereas craving and depressive symptoms were not significantly associated with drinking. The number of heavy drinking days were not significantly associated with demand, craving, or depressive symptoms.

CONCLUSIONS

These results suggest that demand may reflect unique risk for drinking relative to craving or depressive symptoms. These findings provide support for the utility of the APT within a clinical setting to assess individualized valuation of alcohol.

(Neuro)therapeutic Approaches in the Field of Alcohol Use Disorders

Purpose of Review

Alcohol use disorder (AUD) is a burdening chronic condition that is characterized by high relapse rates despite severe negative consequences. There has been a recent emergence of interest in (neuro)therapeutic intervention strategies that largely involve the detrimental change in mechanisms linked to addiction disorders. Most prominently, the latter include habitual decision-making, cue-induced behavioral tendencies, as well as the amplifying effects of stressful events on drinking behavior. This article discusses these learning mechanisms and modification thereof as possible targets of (neuro)therapeutic interventions for AUD.

Recent Findings

Psychological therapies that target dysregulated neurocognitive processes underlying addictive behavior may hold promise as effective treatments for AUD.

Summary

Despite the progression in psychological and neuroscience research in the field of AUD, many behavioral interventions fail to systematically integrate and apply such findings into treatment development. Future research should focus on the targeted modification of the aforementioned processes.

A day-by-day prospective analysis of stress, craving and risk of next day alcohol intake during alcohol use disorder treatment

BACKGROUND

Stress has been known to increase craving in individuals with Alcohol Use Disorders (AUD) and predict future alcohol relapse risk, but whether stress on a particular day affects craving on that day to impact prospective alcohol intake in the real world, particularly during early treatment and recovery, has not been studied thus far.

METHOD

The first study included 85 AUD individuals who reported their daily stress, craving, and alcohol intake in the first two weeks of early treatment. A second validation study included 28 AUD patients monitored daily during eight weeks of outpatient 12-Step based behavioral counseling treatment for AUD. Data were collected from telephone-based daily diaries for 903 days in Study 1 and 1488 in Study 2. Multilevel latent models tested if daily and person-averaged craving mediated the link between stressful events and next day drinking during treatment.

RESULTS

In both Study 1 and 2, exposure to a stressful event on a particular day predicted increased craving on that day (p's≤.002); and such increases in craving predicted the likelihood of drinking the next day (p's≤.014) and the drinking amount (p's< = 008). Individuals who experienced more stressful events reported higher craving (p's≤.012), and higher cravers reported greater next day drinking (p's<.001).

CONCLUSIONS

The results across two studies with separate samples are the first to establish that craving directly mediates the association between stress and next day alcohol intake in individuals with AUD. Findings suggest a need for novel treatment approaches to address stress-induced craving to improve alcohol use outcomes.

Measuring drug dependence in police custody: An item response theory and differential item function analysis of UNCOPE in Australia

INTRODUCTION AND AIMS

Although there has been significant investment in policies and programs aimed at preventing drug-related crime, there has been comparatively little effort dedicated to the validation the relevant research and evidence gathering tools. In this study, we aim to confirm the internal consistency of UNCOPE, developed by Hoffmann and colleagues, in the Australian context, as well as explore whether time in custody and prior custodial experience results in differential item functioning.

DESIGN AND METHODS

Data were derived from the Australian Institute of Criminology's Drug Use Monitoring in Australia Program in which the UNCOPE instrument had been administered with 15 454 detainees who reported illicit drug use in the past 12 months. Item response theory methods are used to explore the characteristics of all six items, while Multiple Indicators Multiple Causes and likelihood ratio differential item functioning test methods are used to explore differential item functioning.

RESULTS

Strong support is indicated for the internal consistency of the UNCOPE instrument. Modest differential functioning is identified for only one item, indicating that prolonged periods of detention prior to interview may influence the probability of endorsement for items that require introspection and reflection on drug-related neglect. These modest effects are unlikely to have any practical effect on the overall utility of UNCOPE.

DISCUSSION AND CONCLUSIONS

In these analyses, the item characteristics of UNCOPE appear consistent with results seen in the USA. Further, the modest differential item functioning identified for neglect (item N) has no practical impact on the overall functioning on UNCOPE. Criminal justice and drug policy researchers will be comforted by the absence of any substantial implementation or environmental bias.

Prescription opioid misusing chronic pain patients exhibit dysregulated context-dependent associations: Investigating associative learning in addiction with the cue-primed reactivity task

BACKGROUND

Associative learning undergirds the development of addiction, such that drug-related cues serve as conditioned stimuli to elicit drug-seeking responses. Plausibly, among opioid misusing chronic pain patients, pain-related information may serve as a conditioned stimulus to magnify opioid cue-elicited autonomic and craving responses through a process of second-order conditioning.

METHODS

We utilized a novel psychophysiological probe of pain-opioid conditioned associations, the Cue-Primed Reactivity (CPR) task. In this task, participants were presented with images as primes (200 ms) and cues (6000 ms) in pairs organized in four task blocks: "control-opioid," "pain-opioid," "control-pain," and "opioid-pain." Opioid-treated chronic pain patients (N = 30) recruited from an Army base in the Western United States were classified as opioid misusers (n = 17) or non-misusers (n = 13) via a validated cutpoint on the Prescription Drug Use Questionnaire (PDUQ; Compton et al., 2008). Opioid misuse status was examined as a predictor of HRV, craving, and mood responses on the CPR task.

RESULTS

HRV increased to a greater extent during the pain-opioid block compared to the control-opioid block for non-misusers compared to misusers (p = .003, η²_partial = 0.27). In contrast, craving increased to a greater extent from baseline to the pain-opioid block for misusers than for non-misusers (p = .03, η²_partial = .16).

CONCLUSIONS

Findings suggest that opioid-treated chronic pain patients exhibit Pavlovian conditioned responses to opioid cues strengthened by an associative learning process of second-order conditioning when primed by pain-related images. This pain-opioid contingency appears to become disrupted among individuals who engage in opioid misuse, such that opioid-related stimuli elicit motivational responses irrespective of pain-related contextual stimuli.

Exacerbated Craving in the Presence of Stress and Drug Cues in Drug-Dependent Patients

In addiction, risk factors for craving and use include stress and drug-related cues. Stress and cues have additive or more-than-additive effects on drug seeking in laboratory animals, but, surprisingly, seem to compete with one another (ie, exert less-than-additive effects) in human laboratory studies of craving. We sought heretofore elusive evidence that human drug users could show additive (or more-than-additive) effects of stress and cues on craving, using ecological momentary assessment (EMA). Outpatients (N=182) maintained on daily buprenorphine or methadone provided self-reports of stress, craving, mood, and behavior on electronic diaries for up to 16 weeks. In three randomly prompted entries (RPs) per day, participants reported the severity of stress and craving and whether they had seen or been offered opioids, cocaine, cannabis, methamphetamine, alcohol, or tobacco. In random-effects models controlling for between-person differences, we tested effects of momentary drug-cue exposure and stress (and their interaction) on momentary ratings of cocaine and heroin craving. For cocaine craving, the Stress × Cue interaction term had a positive mean effect across participants (M=0.019; CL95 0.001-0.036), denoting a more-than-additive effect. For heroin, the mean was not significantly greater than 0, but the confidence interval was predominantly positive (M=0.019; CL95 -0.007-0.044), suggesting at least an additive effect. Heterogeneity was substantial; qualitatively, the Stress × Cue effect appeared additive for most participants, more than additive for a sizeable minority, and competitive in very few. In the field, unlike in human laboratory studies to date, craving for cocaine and heroin is greater with the combination of drug cues and stress than with either alone. For a substantial minority of users, the combined effect may be more than additive.

Sex differences in guanfacine effects on stress-induced stroop performance in cocaine dependence

AIMS

Chronic drug abuse leads to sex-specific changes in drug cue and stress physiologic and neuroendocrine reactivity as well as in neural responses to stress and cue-related challenges and in executive function such as inhibitory control, cognitive flexibility and self control. Importantly, these functions have been associated with high risk of relapse and treatment. Alpha-2 agonism may enhance inhibitory cognitive processes in the face of stress with sex-specific effects, however this has not been previously assessed in cocaine dependence.

METHOD

Forty inpatient treatment-seeking cocaine dependent individuals (13F/27M) were randomly assigned to receive either placebo or up to 3mgs of Guanfacine. Three laboratory sessions were conducted following 3-4 weeks of abstinence, where patients were exposed to three 10-min personalized guided imagery conditions (stress, drug cue, combined stress/cue), one per day, on consecutive days in a random, counterbalanced order. The Stroop task was administered at baseline and immediately following imagery exposure.

RESULTS

Guanfacine treated women improved their performance on the Stroop task following exposure to all 3 imagery conditions compared with placebo women (p=0.02). This improvement in cognitive inhibitory performance was not observed in the men.

CONCLUSIONS

Enhancing the ability to cognitively regulate in the face of stress, drug cues and combined stress and drug cue reactivity may be key targets for medications development in cocaine dependent women.

Self-reported cue-induced physical symptoms of craving as an indicator of cocaine dependence

BACKGROUND

The presence of cocaine dependence is under-recognized by cocaine users and requires a careful standardized interview to be ascertained by clinicians.

OBJECTIVE

To test if past experiences of cue-induced physical symptoms of craving (nausea, vomiting, sweating, shaking, nervousness) before cocaine use could be a useful way to boost the diagnosis of cocaine dependence.

METHODS

A cross-sectional study of 221 cocaine users from several outpatient addiction treatment services in France, addressing the most severe period of cocaine use. DSM-IV cocaine dependence was determined with the MINI International Neuropsychiatric Interview (MINI). Physical symptoms before using cocaine were retrospectively assessed with a single item rated on a 0-5 scale.

RESULTS

The prevalence of DSM-IV cocaine dependence was 84.6%. The mean score on the physical symptoms item was 1.3 (SD 1.3). A cut-off score of ≥ 1 on this item alone resulted in a sensitivity of 62%, a specificity of 88.2%, a positive predictive value of 96.6% and a negative predictive value of 29.7% to detect DSM IV cocaine dependence in this sample. Adding this item to a model with the frequency of cocaine use significantly increased the predictive power: Nagelkerke's R(2) increased from .149 to .326 (p < .001).

DISCUSSION AND CONCLUSION

Recalling past experiences of cue-induced physical signs of cocaine craving is associated with a clinical diagnosis of lifetime cocaine dependence and could be a simple way to improve its detection in clinical settings.

Sex differences in guanfacine effects on drug craving and stress arousal in cocaine-dependent individuals

Currently, no FDA-approved medication exists for the treatment of cocaine use disorder. Furthermore, as women become increasingly more at risk for the consequences of cocaine addiction, the need to establish better-tailored treatment medications is paramount. We examine the effects of the alpha2 adrenergic agonist, guanfacine HCl, on responses to stress and drug cue in a group of cocaine-dependent men and women who also abuse alcohol and nicotine. Forty early abstinent treatment-seeking cocaine-dependent males and females were randomly assigned to receive either daily placebo (12 M/7 F) or guanfacine (2 or 3 mg) (15 M/6 F) for 3 weeks. In week 4, they participated in a laboratory experiment and were exposed to three 10-min guided imagery conditions (stress/stress, cue/cue, and stress/cue), one per day, consecutively in a random, counterbalanced order. Craving, negative emotion, anxiety, and cardiovascular function were assessed at baseline, immediately following imagery exposure, and at various recovery time points. Guanfacine significantly attenuated cocaine craving, alcohol craving, anxiety, and negative emotion following exposure to all three imagery conditions in females, but not males. Guanfacine did, however, reduce sympathetic tone as well as stress and cue-induced nicotine craving and systolic blood pressure (SBP) in both males and females. These findings highlight sex-specific effects of guanfacine on drug craving, anxiety, and negative mood with significant effects in women and not men. The findings suggest further evaluation of guanfacine in the treatment of cocaine use disorder with a specific focus on sex differences in treatment response.

Cognitive and affective mechanisms linking trait mindfulness to craving among individuals in addiction recovery

The present study aimed to identify affective, cognitive, and conative mediators of the relation between trait mindfulness and craving in data culled from an urban sample of 165 persons (in abstinence verified by urinalysis) entering into residential treatment for substance use disorders between 2010 and 2012. Multivariate path analysis adjusting for age, gender, education level, employment status, and substance use frequency indicated that the association between the total trait mindfulness score on the Five Facet Mindfulness Questionnaire and alcohol/drug craving was statistically mediated by negative affect (measured by the PANAS, beta = -.13) and cognitive reappraisal (measured by the CERQ, beta = -.08), but not by readiness to change (measured by the URICA, beta = -.001). Implications for mindfulness-oriented treatment of persons with substance use disorders are discussed. The study's limitations are noted.

Mindfulness training targets neurocognitive mechanisms of addiction at the attention-appraisal-emotion interface

Prominent neuroscience models suggest that addictive behavior occurs when environmental stressors and drug-relevant cues activate a cycle of cognitive, affective, and psychophysiological mechanisms, including dysregulated interactions between bottom-up and top-down neural processes, that compel the user to seek out and use drugs. Mindfulness-based interventions (MBIs) target pathogenic mechanisms of the risk chain linking stress and addiction. This review describes how MBIs may target neurocognitive mechanisms of addiction at the attention-appraisal-emotion interface. Empirical evidence is presented suggesting that MBIs ameliorate addiction by enhancing cognitive regulation of a number of key processes, including: clarifying cognitive appraisal and modulating negative emotions to reduce perseverative cognition and emotional arousal; enhancing metacognitive awareness to regulate drug-use action schema and decrease addiction attentional bias; promoting extinction learning to uncouple drug-use triggers from conditioned appetitive responses; reducing cue-reactivity and increasing cognitive control over craving; attenuating physiological stress reactivity through parasympathetic activation; and increasing savoring to restore natural reward processing. Treatment and research implications of our neurocognitive framework are presented. We conclude by offering a temporally sequenced description of neurocognitive processes targeted by MBIs through a hypothetical case study. Our neurocognitive framework has implications for the optimization of addiction treatment with MBIs.

The role of guanfacine as a therapeutic agent to address stress-related pathophysiology in cocaine-dependent individuals

The pathophysiology of cocaine addiction is linked to changes within neural systems and brain regions that are critical mediators of stress system sensitivity and behavioral processes associated with the regulation of adaptive goal-directed behavior. This is characterized by the upregulation of core adrenergic and corticotropin-releasing factor mechanisms that subserve negative affect and anxiety and impinge upon intracellular pathways in the prefrontal cortex underlying cognitive regulation of stress and negative emotional state. Not only are these mechanisms essential to the severity of cocaine withdrawal symptoms, and hence the trajectory of clinical outcome, but also they may be particularly pertinent to the demography of cocaine dependence. The ability of guanfacine to target overlapping stress, reward, and anxiety pathophysiology suggests that it may be a useful agent for attenuating the stress- and cue-induced craving state not only in women but also in men. This is supported by recent research findings from our own laboratory. Additionally, the ability of guanfacine to improve regulatory mechanisms that are key to exerting cognitive and emotional control over drug-seeking behavior also suggests that guanfacine may be an effective medication for reducing craving and relapse vulnerability in many drugs of abuse. As cocaine-dependent individuals are typically polydrug abusers and women may be at a greater disadvantage for compulsive drug use than men, it is plausible that medications that target catecholaminergic frontostriatal inhibitory circuits and simultaneously reduce stress system arousal may provide added benefits for attenuating cocaine dependence.

The clinical neurobiology of drug craving

Drug craving has re-emerged as a relevant and important construct in the pathophysiology of addiction with its inclusion in DSM-V as a key clinical symptom of addictive disorders. This renewed focus has been due in part to the recent neurobiological evidence on craving-related neural activation and clinical evidence supporting its association with drug use, relapse, and recovery processes. This review covers the neurobiology of drug craving and relapse risk with a primary focus on cocaine addiction and a secondary emphasis on alcohol addiction. A conceptualization of drug craving on the continuum of healthy desire and compulsive seeking, and the associated neurobiological adaptations associated with the development of an increased craving/wanting state is presented. Altered dopamine neurochemistry as well as disrupted prefrontal control and hyperactive striatal-limbic responses in experiencing drug cues, stress, drug intake and in basal relaxed states are identified as neurobiological signatures that predict drug craving and drug use. Thus, the clinical and neurobiological features of the craving/wanting state are presented with specific attention to alterations in these cortico-limbic-striatal and prefrontal self-control circuits that predict drug craving and relapse risk. The methodological challenges that need to be addressed to further develop the evolving conceptual approach to the neuroscience of drug craving is presented, with a focus on identification and validation of biomarkers associated with the craving state and treatment approaches that may be of benefit in reversing the neurobiological adaptations associated with drug craving to improve treatment outcomes in addiction.

Differential roles of thought suppression and dispositional mindfulness in posttraumatic stress symptoms and craving

Exposure to traumatic events often results in severe distress which may elicit self-medication behaviors. Yet, some individuals exposed to trauma do not develop post-traumatic stress symptoms and comorbid addictive impulses. In the wake of traumatic events, psychological processes like thought suppression and mindfulness may modulate post-traumatic stress and craving for substances. We examined the differential roles of mindfulness and suppression in comorbid post-traumatic stress and craving among a sample of 125 persons with extensive trauma histories and psychiatric symptoms in residential treatment for substance dependence. Results indicated that thought suppression, rather than extent of trauma history, significantly predicted post-traumatic stress symptom severity while dispositional mindfulness significantly predicted both post-traumatic stress symptoms and craving. In multiple regression models, mindfulness and thought suppression combined explained nearly half of the variance in post-traumatic stress symptoms and one-quarter of the variance in substance craving. Moreover, multivariate path analysis indicated that prior traumatic experience was associated with greater thought suppression, which in turn was correlated with increased post-traumatic stress symptoms and drug craving, whereas dispositional mindfulness was associated with decreased suppression, post-traumatic stress, and craving. The maladaptive strategy of thought suppression appears to be linked with adverse psychological consequences of traumatic life events. In contrast, dispositional mindfulness appears to be a protective factor that buffers individuals from experiencing more severe post-traumatic stress symptoms and craving.

Stress system changes associated with marijuana dependence may increase craving for alcohol and cocaine

OBJECTIVE

To date, little research exists defining bio-behavioral adaptations associated with both marijuana abuse and risk of craving and relapse to other drugs of abuse during early abstinence.

METHOD

Fifty-nine treatment-seeking individuals dependent on alcohol and cocaine were recruited. Thirty of these individuals were also marijuana (MJ) dependent; 29 were not. Twenty-six socially drinking healthy controls were also recruited. All participants were exposed to three 5-min guided imagery conditions (stress, alcohol/cocaine cue and relaxing), presented randomly, one per day across three consecutive days. Measures of craving, anxiety, heart rate, blood pressure, plasma adrenocorticotrophic hormone and cortisol were collected at baseline and subsequent recovery time points.

RESULTS

The MJ-dependent group showed increased basal anxiety ratings and cardiovascular output alongside enhanced alcohol craving and cocaine craving, and dampened cardiovascular response to stress and cue. They also demonstrated elevated cue-induced anxiety and stress-induced cortisol and adrenocorticotrophic hormone levels, which were not observed in the non-MJ-dependent group or controls. Cue-related alcohol craving and anxiety were both predictive of a shorter number of days to marijuana relapse following discharge from inpatient treatment.

CONCLUSIONS

Findings provide some support for drug cross-sensitization in terms of motivational processes associated with stress-related and cue-related craving and relapse.

Guanfacine effects on stress, drug craving and prefrontal activation in cocaine dependent individuals: preliminary findings

Cocaine dependence is associated with increased stress and drug cue-induced craving and physiological arousal but decreased prefrontal activity to emotional and cognitive challenge. As these changes are associated with relapse risk, we investigated the effects of α2 receptor agonist guanfacine on these processes. Twenty-nine early abstinent treatment-seeking cocaine dependent individuals were randomly assigned to either daily placebo or guanfacine (up to 3 mg) for four weeks. In a laboratory experiment, all patients were exposed to three 10-min guided imagery conditions (stress/stress, drug cue/drug cue, stress/drug cue), one per day, consecutively in a random, counterbalanced order. Subjective craving, anxiety and arousal as well as cardiovascular output were assessed repeatedly. Brain response to stress, drug cue and relaxing imagery was also assessed during a functional magnetic resonance (fMRI) imaging session. In the current study, guanfacine was found to be safe and well-tolerated. Lower basal heart rate and blood pressure was observed in the guanfacine versus placebo group. Guanfacine lowered stress and cue-induced nicotine craving and cue-induced cocaine craving, anxiety and arousal. The guanfacine group also showed increased medial and lateral prefrontal activity following stress and drug cue exposure compared with placebo. Data suggest further exploration of guanfacine is warranted in terms of its potential for reducing stress-induced and cue-induced drug craving and arousal.

Immune system inflammation in cocaine dependent individuals: implications for medications development

OBJECTIVES

Cocaine dependence is a chronic stress state. Furthermore, both stress and substance abuse have robust and reciprocal effects on immune system cytokines, which are known to be powerful modulators of mood. We therefore examine basal and provoked changes in peripheral cytokines in cocaine dependent individuals to better understand their role in the negative reinforcing effects of cocaine.

METHODS

Twenty-eight (16 F/12 M) treatment-seeking cocaine dependent individuals and 27 (14 F/13 M) social drinkers were exposed to three 5-min guided imagery conditions (stress, drug cue, relaxing) presented randomly across consecutive days. Measures of salivary cortisol, tumor necrosis factor alpha (TNFα), interleukin-10 (IL-10), and interleukin-1 receptor antagonist (IL-1ra) were collected at baseline and various post-imagery time-points.

RESULTS

Cocaine abusers demonstrated decreased basal IL-10 compared with social drinkers. They also showed significant elevations in pro-inflammatory TNFα when exposed to stress compared with when they were exposed to relaxing imagery. This was not observed in the social drinkers. Conversely, social drinkers demonstrated increases in the anti-inflammatory markers, IL-10 and IL-1ra, following exposure to cue, which were not seen in the dependent individuals.

CONCLUSIONS

Cocaine dependent individuals demonstrate an elevated inflammatory state both at baseline and following exposure to the stress imagery condition. Cytokines may reflect potentially novel biomarkers in addicted populations for treatment development.

Preclinical validation of a novel cocaine exposure therapy for relapse prevention

BACKGROUND

Cocaine not only induces intense rewarding sensations but also craving for more cocaine, particularly during abstinence, an effect that contributes, together with other factors, to relapse. Here we sought to prevent this effect by extinguishing the conditioned interoceptive cues of cocaine that are thought to be acquired during repeated cocaine use.

METHODS

Cocaine-induced craving was studied in rats using the well-validated model of drug-primed reinstatement of cocaine seeking. To extinguish the conditioned interoceptive effects of cocaine, rats received daily repeated cocaine priming in the absence of drug reinforcement.

RESULTS

Cocaine-primed reinstatement of cocaine seeking dramatically decreased with repeated cocaine priming regardless of the testing dose and even following a history of extended access to cocaine self-administration. The extinction of cocaine-primed reinstatement of cocaine seeking was enduring, generalized to stress-another major trigger of drug craving and relapse-and was context-dependent.

CONCLUSIONS

These findings clearly show that it is feasible to prevent the ability of cocaine and stress to induce cocaine seeking using an approach designed to extinguish the drug's conditioned interoceptive cues. Although this preclinical extinction approach has limitations that need to be overcome in future research (i.e., its context-dependency), it may nevertheless represent a promising basis for the development of a novel exposure therapy against cocaine relapse.

Targeting cognitive-affective risk mechanisms in stress-precipitated alcohol dependence: an integrated, biopsychosocial model of automaticity, allostasis, and addiction

This paper proposes a novel hypothetical model integrating formerly discrete theories of stress appraisal, neurobiological allostasis, automatic cognitive processing, and addictive behavior to elucidate how alcohol misuse and dependence are maintained and re-activated by stress. We outline a risk chain in which psychosocial stress initiates physiological arousal, perseverative cognition, and negative affect that, in turn, triggers automatized schema to compel alcohol consumption. This implicit cognitive process then leads to attentional biases toward alcohol, subjective experiences of craving, paradoxical increases in arousal and alcohol-related cognitions due to urge suppression, and palliative coping through drinking. When palliative coping relieves distress, it results in negative reinforcement conditioning that perpetuates the cycle by further sensitizing the system to future stressful encounters. This model has implications for development and implementation of innovative behavioral interventions (such as mindfulness training) that disrupt cognitive-affective mechanisms underpinning stress-precipitated dependence on alcohol.

Trait Mindfulness Predicts Attentional and Autonomic Regulation of Alcohol Cue-Reactivity

BACKGROUND

The trait of mindfulness varies among meditation-naïve individuals and is associated with attentional and autonomic regulation, two neurocognitive functions that become impaired in addiction. It was hypothesized that alcohol dependent inpatients with comparatively high levels of trait mindfulness would exhibit significant autonomic recovery from stress-primed alcohol cues mediated by greater attentional disengagement from such cues.

METHODS

58 alcohol dependent inpatients participated in affect-modulated psychophysiological cue-reactivity protocol and a spatial cueing task designed to assess alcohol attentional bias (AB). Associations between trait mindfulness, alcohol AB, and an index of autonomic activity, high-frequency heart rate variability (HFHRV), were examined via multivariate path analysis.

RESULTS

Higher trait mindfulness was significantly associated with less difficulty resisting the urge to drink and greater HFHRV recovery from stress-primed alcohol cues. After statistically controlling for the correlation of mindfulness and perceived difficulty resisting drinking urges, the association between mindfulness and HFHRV recovery was partially mediated by attentional disengagement from alcohol cues (model R² = .30).

DISCUSSION

Alcohol dependent inpatients higher in mindfulness are better able to disengage attention from alcohol cues, which in turn predicts the degree of HFHRV recovery from such cues. Trait mindfulness may index cognitive control over appetitive responses reflected in superior attentional and autonomic regulation of stress-primed alcohol cue-reactivity.