The role of interoception in addiction: A critical review

Reduced Segregation Between Cognitive and Emotional Processes in Cannabis Dependence

Addiction is characterized by an erosion of cognitive control toward drug taking that is accentuated by negative emotional states. Here we tested the hypothesis that enhanced interference on cognitive control reflects a loss of segregation between cognition and emotion in addiction. We analyzed Human Connectome Project data from 1206 young adults, including 89 with cannabis dependence (CD). Two composite factors, one for cognition and one for emotion, were derived using principal component (PC) analyses. Component scores for these PCs were significantly associated in the CD group, such that negative emotionality correlated with poor cognition. However, the corresponding component scores were uncorrelated in matched controls and nondependent recreational cannabis users (n = 87). In CD, but not controls or recreational users, functional magnetic resonance imaging activations to emotional stimuli (angry/fearful faces > shapes) correlated with activations to cognitive demand (working memory; 2-back > 0-back). Canonical correlation analyses linked individual differences in cognitive and emotional component scores with brain activations. In CD, there was substantial overlap between cognitive and emotional brain-behavior associations, but in controls, associations were more restricted to the cognitive domain. These findings support our hypothesis of impaired segregation between cognitive and emotional processes in CD that might contribute to poor cognitive control under conditions of increased emotional demand.

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.

The self’s choice: Priming attentional focus on bodily self promotes loss frequency bias

When attention is focused on self representation(s), the ability to evaluate one’s internal sensations is enhanced, according to previous research by Ainley and colleagues (Consciousness and Cognition, 22(4), 1231–1238, 2013). Self-representations are usually distinguished between bodily and narrative. Both bodily and narrative representations improve decision-making processes, in that the consideration of alternatives is informed by sensations experienced deep inside the body (e.g., anxiety) as suggest by the literature (Noël, Brevers & Bechara in Frontiers in Psychiatry, 4, 179,  2013). The objective of the present study is to analyze the decision-making process in multiple conditions of stimulated self-representations. Participants played the Iowa Gambling Task three times (a baseline without stimuli and two randomly ordered stimulations to prime bodily and narrative self-representations). While no significant differences emerged regarding advantageous choices, participants showed loss frequency bias in the condition with bodily-self representation priming. Two interpretations are proposed: bodily-self focus acted as a distractor diminishing participants’ commitment to long term outcomes or enhanced interoception promoted aversion to losses. Directions are given for future research and clinical implications.

Perceptual insensitivity to the modulation of interoceptive signals in depression, anxiety, and substance use disorders

This study employed a series of heartbeat perception tasks to assess the hypothesis that cardiac interoceptive processing in individuals with depression/anxiety (N = 221), and substance use disorders (N = 136) is less flexible than that of healthy individuals (N = 53) in the context of physiological perturbation. Cardiac interoception was assessed via heartbeat tapping when: (1) guessing was allowed; (2) guessing was not allowed; and (3) experiencing an interoceptive perturbation (inspiratory breath hold) expected to amplify cardiac sensation. Healthy participants showed performance improvements across the three conditions, whereas those with depression/anxiety and/or substance use disorder showed minimal improvement. Machine learning analyses suggested that individual differences in these improvements were negatively related to anxiety sensitivity, but explained relatively little variance in performance. These results reveal a perceptual insensitivity to the modulation of interoceptive signals that was evident across several common psychiatric disorders, suggesting that interoceptive deficits in the realm of psychopathology manifest most prominently during states of homeostatic perturbation.

Vulnerability to addiction

Addiction is a chronic brain disease that has dramatic health and socioeconomic consequences worldwide. Multiple approaches have been used for decades to clarify the neurobiological basis of this disease and to identify novel potential treatments. This review summarizes the main brain networks involved in the vulnerability to addiction and specific innovative technological approaches to investigate these neural circuits. First, the evolution of the definition of addiction across the Diagnostic and Statistical Manual of Mental Disorders (DSM) is revised. We next discuss several innovative experimental techniques that, combined with behavioral approaches, have allowed recent critical advances in understanding the neural circuits involved in addiction, including DREADDs, calcium imaging, and electrophysiology. All these techniques have been used to investigate specific neural circuits involved in vulnerability to addiction and have been extremely useful to clarify the neurobiological basis of each specific component of the addictive process. These novel tools targeting specific brain regions are of great interest to further understand the different aspects of this complex disease. This article is part of the special issue on 'Vulnerabilities to Substance Abuse.'.

Interventions and Manipulations of Interoception

Interoceptive pathways may be manipulated at various levels to develop interventions to improve symptoms in a range of disorders. Primarily through the lens of the respiratory system, we outline various pathways that can be manipulated at neural, behavioral, and psychological levels to change the representation of and attention to interoceptive signals, which can alter interconnected physiological systems and improve functioning and adaptive behavior. Interventions can alter interoception via neuromodulation of the vagus nerve, slow breathing to change respiratory rate and depth, or awareness processes such as mindfulness-based interventions. Aspects of this framework may be applied to other physiological systems and future research may integrate interventions across multiple levels of manipulation or bodily systems.

Interoceptive Awareness, Decision-Making and Impulsiveness in Male Patients with Alcohol or Opioid Use Disorder

BACKGROUND

The present study was prepared on the assumption that interoceptive awareness (IA) and decision-making processes are implicated in addiction, and that somatic feedback plays an important role in decision-making.

METHODS

The study participants included 80 abstinent male inpatients with alcohol use disorder (n = 40) or opioid use disorder (n = 40) according to DSM-5 criteria (current severity: moderate or severe), along with 40 healthy male volunteers. All participants performed the heart rate tracking task as an objective physiological performance measure of IA and a computerized version of the Iowa gambling task (IGT) as a validated measure of decision-making. Impulsiveness was assessed using the Barratt Impulsiveness Scale 11 (BIS-11). Craving was evaluated with the Penn Alcohol Craving Scale (PACS) or Substance Craving Scale (SCS).

RESULTS

(1) Heartbeat perception (HBP) and IGT scores were similar between the patients with alcohol or opioid addiction, being significantly lower than those in the control group, and the difference remained significant even when controlling for the factors that were significant in bivariate analyses; (2) HBP scores of patients correlated significantly with IGT scores, even when controlling the effect of the related variables; (3) BIS-11 scores of patients negatively correlated significantly with HBP scores and did not correlate significantly with IGT scores; and (4) PACS/SCS scores did not correlate significantly with HBP and IGT scores.

CONCLUSIONS

Our findings support the hypothesis that IA and decision-making processes are implicated in addiction and that decreased IA is associated with impaired decision-making.

Interoception and alcohol addiction: Vagotomy induces long-lasting suppression of relapse-type behavior

Drug addictions are chronic mental disorders characterized by compulsive drug seeking and drug use, despite their negative consequences. It is a priority to find therapeutic alternatives to prevent relapse, as there are still no treatments that can ensure abstinence. One of the neural systems implicated in the appearance of the states of discomfort that motivate relapse is the interoceptive system, which oversees our internal body states. However, less attention has been given to the peripheral components of the interoceptive system and their role in addictions. Within these pathways, the vagus nerve represents one of the main visceral afferents of the interoceptive system. We hypothesized that the interruption of visceral afferent pathways would decrease the motivational effects of the drug, thereby either decreasing or preventing drug cravings. To test this idea, we used rats of a high-alcohol-drinking line and measured the effect that vagus nerve resection had on the relapse-like alcohol drinking, expressed as the alcohol deprivation effect, a phenomenon that has been linked to addiction-related events such as alcohol cravings. We found that even though vagotomy completely eliminates the effect of alcohol deprivation, it has no impact on water consumption or animal weight. These results give us valuable information about the relationship between the autonomic nervous system and alcohol use disorders and allow us to propose new clinical research that might have translational options.

Appetitive Motivation and Regulatory Processes in Adolescent Ketamine Users

Ketamine has remained the most commonly used illicit drug among adolescents in Taiwan. A dual process model proposes that addictive behaviors develop in adolescents as a result of an imbalance between an appetitive, approach-oriented system (implicit and explicit attitudes) and a regulatory executive system (cool and hot executive functions). We aimed to examine the appetitive and regulatory processes in adolescent ketamine users in comparison to matched healthy adolescents. Method: The participants were 30 adolescent ketamine users and 32 nondrug controls, matched with gender, age, education years, and education systems. Both groups completed the affective priming task (APT), the stop-signal task (SST), an Iowa Gambling Task (IGT), and finally a Drug Use Disorders Identification Test: Extended (DUDIT-E). Results: The controls had higher positive and negative outcome expectancy with respect to using ketamine compared to the adolescent ketamine users. There was no significant between-group performance difference in APT. The adolescent ketamine users may have shown marginally poorer performance compared to the controls in hot executive functions (IGT), but their cold executive functions (SST) remained intact. Conclusion: The current study reported that the adolescent ketamine users may not have imbalanced dual processes (biased appetitive motivation and impaired regulatory executive process). A different therapeutic focus on adolescent ketamine users may be developed accordingly. More advocacies on ketamine's aversive outcomes are needed, particularly on campus in order to reduce substance misuse.

An interoceptive basis for alcohol priming effects

RATIONALE

Alcohol priming can modulate the value of rewards, as observed through the effects of acute alcohol administration on cue reactivity. However, little is known about the psychophysiological mechanisms driving these effects. Here, we examine how alcohol-induced changes in bodily states shape the development of implicit attentional biases and explicit cue reactivity.

OBJECTIVES

To characterize the interoceptive correlates of alcohol priming effects on alcohol attentional biases and cue reactivity.

METHODS

In a two-session double-blind alcohol administration procedure, participants (n=31) were given a 0.4-g/kg dose of alcohol or a placebo drink. Cardiovascular responses were measured before and after alcohol administration to observe the effects of alcohol on viscero-afferent reactivity, as indexed through changes in heart rate variability (HRV) at or near 0.1 Hz (0.1-Hz HRV). Next, participants completed a modified flanker task to examine implicit alcohol attentional biases and provided subjective valence and arousal ratings of alcohol cues to examine explicit cue reactivity.

RESULTS

We found that changes in 0.1-Hz HRV after alcohol administration positively correlated with attentional biases, and negatively correlated with alcohol valence ratings; blood alcohol content was a null predictor.

CONCLUSIONS

This is novel evidence that suggests alcohol-induced changes in bodily states may mediate the occurrence of alcohol priming effects and highlights the potentially generative role of interoceptive mechanisms in alcohol-related behaviors. The differential patterns revealed by implicit biases and explicit response tendencies are considered within the context of the dissociation between wanting and liking.

Impact of a computerized intervention for high distress intolerance on cannabis use outcomes: A randomized controlled trial

OBJECTIVE

Prevalence of regular cannabis use and cannabis use disorder (CUD) have increased in the past two decades, but treatment-seeking is low and extant brief interventions do not target causal risk factors implicated in etiological models of addiction. Elevated distress intolerance (DI) is one risk factor that has been empirically linked with greater CUD severity and maintenance in regular users, but, to our knowledge, research has never targeted it in a brief intervention among cannabis users with CUD or at high risk. The current RCT evaluated the impact of a DI intervention (i.e., Distress Tolerance Intervention [DTI]) compared to a healthy habits control intervention (i.e., Healthy Video Control [HVC]) on DI and cannabis use outcomes.

METHOD

We randomized cannabis users with high DI (N = 60) to the DTI or HVC condition and they received two computerized intervention sessions. We assessed relief cannabis craving at pre- and post-treatment; and we assessed DI, cannabis use coping motives, use-related problems, and use frequency at pre- and post-treatment as well as one- and four-month follow-ups. We assessed CUD symptoms via interviews at pre-treatment and four-month follow-up.

RESULTS

Significant, durable reductions in DI and all cannabis use outcomes occurred in both conditions. Compared to the HVC condition, the DTI led to greater reductions in use frequency during the treatment period. Reductions in self-reported DI were correlated with reductions in coping motives and CUD symptoms.

CONCLUSION

The DTI's impact on all outcomes was largely comparable to the control condition, though it may have utility as an adjunctive intervention.

Bodily Maps of Emotion in Major Depressive Disorder

Background

Emotions play a central role in mental disorder and especially in depression. They are sensed in the body, and it has recently been shown in healthy participants that these sensations can be differentiated between emotions. The aim of the current study was to assess bodily sensations for basic emotions induced by emotion eliciting pictures in depression.

Methods

30 healthy controls (HC), 30 individuals suffering from Major depressive disorder (MDD) without medication use (MDDnm) and 30 individuals with MDD with medication use (MDDm) were shown emotional and neutral pictures and were asked to paint areas in an empty body silhouette where they felt an increase or decrease in activation. Body sensation maps were then calculated and statistical pattern recognition applied.

Results

Results indicated statistically separable activation patterns for all three groups. MDDnm showed less overall activation than HCs, especially in sadness and fear, while MDDm showed stronger deactivation for all emotions than the other two groups.

Conclusions

We could show that emotion experience was associated with bodily sensations that are weaker in depression than in healthy controls and that antidepressant medication was correlated with an increased feeling of bodily deactivation. Results give insights into the relevance for clinicians to acknowledge bodily sensations in the treatment of depression.

Forebrain projection neurons target functionally diverse respiratory control areas in the midbrain, pons, and medulla oblongata

Eupnea is generated by neural circuits located in the ponto-medullary brainstem, but can be modulated by higher brain inputs which contribute to volitional control of breathing and the expression of orofacial behaviors, such as vocalization, sniffing, coughing, and swallowing. Surprisingly, the anatomical organization of descending inputs that connect the forebrain with the brainstem respiratory network remains poorly defined. We hypothesized that descending forebrain projections target multiple distributed respiratory control nuclei across the neuroaxis. To test our hypothesis, we made discrete unilateral microinjections of the retrograde tracer cholera toxin subunit B in the midbrain periaqueductal gray (PAG), the pontine Kölliker-Fuse nucleus (KFn), the medullary Bötzinger complex (BötC), pre-BötC, or caudal midline raphé nuclei. We quantified the regional distribution of retrogradely labeled neurons in the forebrain 12-14 days postinjection. Overall, our data reveal that descending inputs from cortical areas predominantly target the PAG and KFn. Differential forebrain regions innervating the PAG (prefrontal, cingulate cortices, and lateral septum) and KFn (rhinal, piriform, and somatosensory cortices) imply that volitional motor commands for vocalization are specifically relayed via the PAG, while the KFn may receive commands to coordinate breathing with other orofacial behaviors (e.g., sniffing, swallowing). Additionally, we observed that the limbic or autonomic (interoceptive) systems are connected to broadly distributed downstream bulbar respiratory networks. Collectively, these data provide a neural substrate to explain how volitional, state-dependent, and emotional modulation of breathing is regulated by the forebrain.

A Bayesian computational model reveals a failure to adapt interoceptive precision estimates across depression, anxiety, eating, and substance use disorders

Recent neurocomputational theories have hypothesized that abnormalities in prior beliefs and/or the precision-weighting of afferent interoceptive signals may facilitate the transdiagnostic emergence of psychopathology. Specifically, it has been suggested that, in certain psychiatric disorders, interoceptive processing mechanisms either over-weight prior beliefs or under-weight signals from the viscera (or both), leading to a failure to accurately update beliefs about the body. However, this has not been directly tested empirically. To evaluate the potential roles of prior beliefs and interoceptive precision in this context, we fit a Bayesian computational model to behavior in a transdiagnostic patient sample during an interoceptive awareness (heartbeat tapping) task. Modelling revealed that, during an interoceptive perturbation condition (inspiratory breath-holding during heartbeat tapping), healthy individuals (N = 52) assigned greater precision to ascending cardiac signals than individuals with symptoms of anxiety (N = 15), depression (N = 69), co-morbid depression/anxiety (N = 153), substance use disorders (N = 131), and eating disorders (N = 14)-who failed to increase their precision estimates from resting levels. In contrast, we did not find strong evidence for differences in prior beliefs. These results provide the first empirical computational modeling evidence of a selective dysfunction in adaptive interoceptive processing in psychiatric conditions, and lay the groundwork for future studies examining how reduced interoceptive precision influences visceral regulation and interoceptively-guided decision-making.

The role of the vestibular system in value attribution to positive and negative reinforcers

Somatic inputs originating from bioregulatory processes can guide cognition and behavior. One such bodily signal, mostly overlooked so far, is represented by visuo-vestibular coupling and its alteration, which in extreme cases may result in motion sickness. We argued that the inherently perturbed interoceptive state that follows can be a powerful determinant of human motivated behavior, resulting in a blunted response to appetitive stimuli and an exaggerated response to noxious ones. We sought to assess such differential impact of visuo-vestibular mismatches on value through a task involving conflict monitoring. We therefore administered to 42 healthy participants a modified version of the Flankers task, in which distractors (arrows, pointing in either a congruent or incongruent direction) signaled the availability of monetary incentives (gains, losses, or neutral trials). While performing the task, participants received either galvanic vestibular stimulation (GVS), or sham stimulation. We have found impaired behavioral performances when value, which was attached to task-irrelevant information, was at stake. Gains and losses, interestingly, dissociated, and only the latter caused enhanced interference costs in the task, suggesting that negative incentives may be more effective in capturing human attention than positive ones. Finally, we have found some weak evidence for GVS to further increase the processing of losses, as suggested by even larger interference costs in this condition. Results were, however, overall ambiguous, and suggest that much more research is needed to better understand the link between the vestibular system and motivation.

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.

Continuous High Frequency Deep Brain Stimulation of the Rat Anterior Insula Attenuates the Relapse Post Withdrawal and Strengthens the Extinction of Morphine Seeking

Deep brain stimulation (DBS) modulates the neuronal activity in specific brain circuits and has been recently considered as a promising intervention for refractory addiction. The insula cortex is the hub of interoception and is known to be involved in different aspects of substance use disorder. In the present study, we investigate the effects of continuous high frequency DBS in the anterior insula (AI) on drug-seeking behaviors and examined the molecular mechanisms of DBS action in morphine-addicted rats. Sprague-Dawley rats were trained to the morphine-conditioned place preference (CPP, day 1-8) followed by bilaterally implanted with DBS electrodes in the AI (Day 10) and recovery (Day 10-15). Continuous high-frequency (HF) -DBS (130 Hz, 150 μA, 90 μs) was applied during withdrawal (Day 16-30) or extinction sessions. CPP tests were conducted on days 16, 30, 40 during withdrawal session and several rats were used for proteomic analysis on day 30. Following the complete extinction, morphine-CPP was reinstated by a priming dose of morphine infusion (2 mg/kg). The open field and novel objective recognition tests were also performed to evaluate the DBS side effect on the locomotion and recognition memory. Continuous HF-DBS in the AI attenuated the expression of morphine-CPP post-withdrawal (Day 30), but morphine addictive behavior relapsed 10 days after the cessation of DBS (Day 40). Continuous HF-DBS reduced the period to full extinction of morphine-CPP and blocked morphine priming-induced recurrence of morphine addiction. HF-DBS in the AI had no obvious effect on the locomotor activity and novel objective recognition and did not cause anxiety-like behavior. In addition, our proteomic analysis identified eight morphine-regulated proteins in the AI and their expression levels were reversely changed by HF-DBS. Continuous HF-DBS in the bilateral anterior insula prevents the relapse of morphine place preference after withdrawal, facilitates its extinction, blocks the reinstatement induced by morphine priming and reverses the expression of morphine-regulated proteins. Our findings suggest that manipulation of insular activity by DBS could be a potential intervention to treat substance use disorder, although future research is warranted.

Computational models of drug use and addiction: A review

In this brief review, we describe current computational models of drug-use and addiction that fall into 2 broad categories: mathematically based models that rely on computational theories, and brain-based models that link computations to brain areas or circuits. Across categories, many are models of learning and decision-making, which may be compromised in addiction. Several mathematical models take predictive coding approaches, focusing on Bayesian prediction error. Other models focus on learning processes and (traditional) prediction error. Brain-based models have incorporated prefrontal cortex, basal ganglia, and the dopamine system, based on the effects of drugs on dopamine, motivation, and executive control circuits. Several models specifically describe how behavioral control may transition from habitual to goal-directed systems, consistent with computational accounts of compromised "model-based" control. Some brain-based models have linked this to the transition of behavioral control from ventral to dorsal striatum. Overall, we propose that while computational models capture some aspects of addiction and have advanced our thinking, most have focused on the effects of drug use rather than addiction per se, most have not been tested on and/or supported by human data, and few capture multiple stages and symptoms of addiction. We conclude by suggesting a path forward for computational models of addiction. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Is craving a risk factor for substance use among treatment-seeking individuals with alcohol and other drugs use disorders? A meta-analytic review

BACKGROUND

It is still unclear whether craving should be considered a key risk factor for substance-use behaviors (SUB) among treatment-seeking individuals with alcohol (AUD) and other drugs use disorders. Therefore, this study aims at clarifying this topic using a meta-analytic approach.

METHODS

Cohen's d was computed as effect size (ES) measure. Heterogeneity of ESs was computed using the Q statistic and I² index. The analyses also evaluated the impact assessment length on ESs. Furthermore, proximal effects of craving on SUB were compared to distal ones. The diagnoses of specific substance use disorders (SUDs), together with assessment instruments and research design were considered as additional moderators.

RESULTS

Thirty-six independent studies were included for a total of 4868 treatment-seeking individuals with SUDs. Patients who used substances showed slightly higher levels of craving than abstinent ones. The heterogeneity of results was large and significant. The length of period of assessment was positively related to ESs. The analyses highlighted no differences between pooled ESs of proximal and distal impacts of craving on SUB. The diagnoses of SUDs were significant moderators. Considering AUD, assessment instruments and research design were additional moderators.

CONCLUSIONS

Craving is a modest time-dependent proximal and distal risk factor for SUB among individuals with SUDs. Both the frequency of craving episodes and a heightened reactivity to craving cues are largely associated to SUB among individuals with AUD. Future studies should evaluate the mediating and moderating roles of self-regulatory mechanisms on the relationship between craving and SUB.

DUI offenders display reduced perception of intoxication and heightened impulsive choice in response to alcohol

Driving under the influence (DUI) of alcohol continues to be a major contributor in traffic fatalities. There is growing evidence for heightened trait impulsivity in DUI offenders, but little is known about how impulsivity could interact with alcohol intoxication in a manner that would increase the likelihood of driving while intoxicated. This placebo-controlled study examined the acute effects of 0.65g/kg alcohol on 2 facets of impulsivity (impulsive choice and response inhibition), simulated risky driving behavior, and subjective intoxication in a group of 20 DUI offenders and 20 control drivers with no history of DUI. It was predicted that compared with controls, DUI offenders would self-report greater impulsivity, and display greater impulsive choice and driver risk taking, particularly in response to alcohol. Results showed that alcohol impaired drivers' inhibitory control and increased their impulsive choice behavior and risky driving behavior. Alcohol selectively increased impulsive choice of DUI offenders, as control drivers showed no alcohol-induced increase in their impulsive choices. Results also showed that, compared with controls, offenders reported feeling less intoxicated and were more willing to drive after drinking. Laboratory studies are beginning to show that DUI offenders differ from nonoffenders in their acute responses to alcohol. This study identified two alcohol response characteristics of DUI offenders that indicate their lack of risk awareness during intoxication: heightened impulsivity and reduced subjective intoxication. Strategies and treatments to alter these response characteristics in DUI offenders could enhance their risk awareness during the intoxicated state and possibly reduce risk of DUI recidivism. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Diminished responses to bodily threat and blunted interoception in suicide attempters

Psychological theories of suicide suggest that certain traits may reduce aversion to physical threat and increase the probability of transitioning from suicidal ideation to action. Here, we investigated whether blunted sensitivity to bodily signals is associated with suicidal action by comparing individuals with a history of attempted suicide to a matched psychiatric reference sample without suicide attempts. We examined interoceptive processing across a panel of tasks: breath-hold challenge, cold-pressor challenge, and heartbeat perception during and outside of functional magnetic resonance imaging. Suicide attempters tolerated the breath-hold and cold-pressor challenges for significantly longer and displayed lower heartbeat perception accuracy than non-attempters. These differences were mirrored by reduced activation of the mid/posterior insula during attention to heartbeat sensations. Our findings suggest that suicide attempters exhibit an 'interoceptive numbing' characterized by increased tolerance for aversive sensations and decreased awareness of non-aversive sensations. We conclude that blunted interoception may be implicated in suicidal behavior.

Do Adolescents Use Substances to Relieve Uncomfortable Sensations? A Preliminary Examination of Negative Reinforcement among Adolescent Cannabis and Alcohol Users

Alcohol and cannabis use are highly prevalent among adolescents and associated with negative consequences. Understanding motivations behind substance use in youth is important for informing prevention and intervention efforts. The present study aims to examine negative reinforcement principles of substance use among adolescent cannabis and alcohol users by pairing a cue reactivity paradigm with an aversive interoceptive stimulus. Adolescents (ages 15–17), classified as controls (CTL; n = 18), cannabis and/or alcohol experimenters (CAN+ALC-EXP; n = 16), or individuals meeting clinical criteria for cannabis and/or alcohol use disorder (CAN+ALC-SUD; n = 13) underwent functional magnetic resonance imaging during which they experienced an aversive interoceptive probe delivered via breathing load while simultaneously performing a cue reactivity paradigm. Participants also provided self-report ratings of how their substance use is positively or negatively reinforced. While experiencing the breathing load, CAN+ALC-SUD exhibited greater (p < 0.05) deactivation in the right amygdala, the left inferior frontal gyrus, and the left parahippocampal gyrus than CAN+ALC-EXP and CTL, who did not differ. Across all substance users, activation during the breathing load within the left parahippocampal gyrus negatively correlated with cannabis and alcohol lifetime use episodes and the left inferior frontal gyrus activity negatively correlated with lifetime alcohol use episodes. CAN+ALC-SUD reported experiencing more positive and negative reinforcement of using their substance of choice than CAN+ALC-EXP; both user groups reported higher levels of positive than negative reinforcement. Adolescents with a cannabis/alcohol use disorder demonstrate an altered response to interoceptive perturbations. However, adolescent cannabis/alcohol use does not appear to be driven by negative reinforcement, as viewing substance images did not dampen this response. Based on self-report data, the experience of positive reinforcement may be stronger for adolescents. Future studies should examine whether positive reinforcement contributes to adolescent substance use.

Unpacking common and distinct neuroanatomical alterations in cocaine dependent versus pathological gambling

Pathological gambling and cocaine dependence are highly pervasive disorders. Functional neuroimaging evidence implicates aberrant activity of prefrontal striatal pathways in both disorders. It is unclear if the neuroanatomy of these areas is also affected. Participants with pathological gambling (n = 18), cocaine dependence (n = 19) and controls (n = 21) underwent high-resolution structural MRI scan and cognitive assessments. In line with emerging functional neuroimaging findings, we hypothesised (i) lower volumes of corticostriatal areas ascribed to decision-making/inhibitory control, craving and reward processing (i.e., orbitofrontal cortex, inferior frontal gyrus, amygdala, striatum, insula) in both pathological gamblers and cocaine dependent participants versus controls; (ii) selected dopaminergic/glutamatergic pathways directly taxed by cocaine (i.e., superior, dorsolateral and anterior cingulate cortices) would be altered in cocaine dependent versus control participants only. Analyses were conducted with a bonferroni correction. Our results showed that both pathological gambling and cocaine dependent participants, compared to controls, had larger volumes of the right inferior frontal gyrus (ps <.01, ds = 0.66 and 0.62). Cocaine dependent participants had lower nucleus accumbens and medial orbitofrontal cortex volumes than pathological gamblers (ps <.05, ds = 0.51 and 0.72), with the latter being predicted by higher negative urgency scores. Inferior frontal gyrus volume may reflect common alterations of cocaine and gambling addictions, whereas cocaine dependence may be uniquely associated with reduced volume in dorsolateral and middle frontal regions. Cocaine's supra-physiological effects on mesolimbic neurons may explain reduced accumbens-orbitofrontal structure compared to gambling.

Getting to the Heart of Low Sensitivity to Alcohol: Context Moderates Low Cardiovascular Response to Alcohol in Persons With a Family History of Alcohol Use Disorder

Background

Low sensitivity to alcohol in persons with a family history of alcoholism (FH+), compared to those without (FH−), contributes to risk for alcohol use disorder (AUD). However, sensitivity of FH+ cardiovascular response to alcohol is not well understood. This gap is significant because cardiovascular processes contribute to emotional regulation and stress response problems theorized to be central to the development and persistence of AUD. This study compared changes in heart rate (HR) and HR variability (HRV) between FH groups after consuming alcohol and control beverages and examined how these changes were moderated by emotional and alcohol‐related contexts.

Methods

Young adults (N = 165) with FH+ (n = 110) or FH− (n = 55) each completed 2 sessions, separated by 1 week. They received one of 3 different beverages (alcohol, placebo, and told‐no‐alcohol) in each session. Electrocardiogram data were recorded during pre–beverage consumption and post–beverage consumption baselines, and then during 4 picture cue tasks (neutral, positive, negative, and alcohol‐related). Generalized estimating equations were used to examine differences in cardiovascular reactivity (changes in HR and HRV power at ~ 0.1 Hz) across FH groups, beverage conditions, and picture cue tasks.

Results

A significant beverage condition × cue task × FH interaction effect on HRV was observed. The FH+ group, compared to the FH− group, showed (a) significantly less HRV suppression in specific cue contexts following alcohol, (b) a mixed pattern of more and less HRV suppression across cue contexts following placebo, and (c) a similar HRV reactivity pattern in the told‐no‐alcohol condition across cue tasks. For HR, there were no significant effects involving FH.

Conclusions

Diminished cardiovascular sensitivity to oral alcohol in FH+ persons varied within a given drinking episode depending on emotional and alcohol‐related features of the context, suggesting that environmental characteristics play a role in the expression of low sensitivity to alcohol among FH+ individuals.

A pilot study of mindful body awareness training as an adjunct to office-based medication treatment of opioid use disorder

The purpose of this study was to pilot-test a mind-body intervention called Mindful Awareness in Body-oriented Therapy (MABT) as an adjunct to buprenorphine for individuals with opioid use disorder (OUD). MABT, a manualized 8 week protocol, teaches interoceptive awareness skills to promote self-care and emotion regulation. A small study was designed to assess MABT recruitment and retention feasibility, and intervention acceptability, among this population. Individuals were recruited from two office-based programs providing buprenorphine treatment within a large urban community medical center. Participants were randomized to receive either treatment as usual (TAU), or TAU plus MABT. Assessments administered at baseline and 10-week follow-up included validated self-report health questionnaires and a process measure, the Multidimensional Assessment of Interoceptive Awareness, to examine interoceptive awareness skills. An additional survey and exit interview for those in the MABT study arm were administered to assess intervention satisfaction. Results showed the ability to recruit and enroll 10 participants within two-weeks, and no loss to follow-up. The MABT study group showed an increase in interoceptive awareness skills from baseline to follow-up, whereas the control group did not. Responses to the satisfaction questionnaire and exit interview were positive, indicating skills learned, satisfaction with the interventionists, and overall perceived benefit of the intervention. In summary, study results demonstrated recruitment and retention feasibility, and high intervention acceptability. This pilot study suggests preliminary feasibility of successfully implementing a larger study of MABT as an adjunct to office-based medication treatment for opioid use disorder.

The relationship between mindfulness and objective measures of body awareness: A meta-analysis

Although awareness of bodily sensations is a common mindfulness meditation technique, studies assessing the relationship between mindfulness and body awareness have provided mixed results. The current study sought to meta-analytically examine the relationship between mindfulness operationalized as a dispositional trait or a construct trained through short- (i.e., randomized controlled trials [RCTs]) or long-term mindfulness meditation practice with objective measures of body awareness accuracy. PubMed, Web of Science, PsycINFO, and Scopus were searched. Studies were eligible if they reported the association between mindfulness and body awareness, were published in English, and included adults. Across 15 studies (17 independent samples), a small effect was found linking mindfulness with greater body awareness accuracy (g = 0.21 [0.08, 0.34], N = 879). When separated by study design, only RCTs continued to show a significant relationship (g = 0.20, [0.02, 0.38], k = 7, n = 505). Heterogeneity of effects was low (I² < 25%), although with wide confidence intervals. Effects were not moderated by study quality. Low fail-safe N estimates reduce confidence in the observed effects. Results suggest a small but potentially detectable relationship between mindfulness and body awareness accuracy. Future investigations could examine individual differences in body awareness as a mechanism within mindfulness interventions.

Sexual trauma history is associated with reduced orbitofrontal network strength in substance-dependent women

AIM

Substance use disorders (SUDs) are highly comorbid with post-traumatic stress disorder (PTSD). PTSD-SUD comorbidity is associated with greater functional impairments and relapse risk. Women with SUDs experience markedly higher rates of trauma and PTSD compared to men with SUDs, particularly due to sexual and domestic abuse. Despite the strong association between trauma exposure and SUDs, the neurobiological correlates are understudied, particularly among females with SUDs. However, there is indication of abnormal somatic and interoceptive processing in women with PTSD. The present study examines interoception-linked differences in intrinsic brain networks in a group of women with SUDs and varying histories of trauma exposure, some of whom have a current PTSD diagnosis.

METHODS

Pre-intervention data were analyzed from a subset (N = 43) of women in SUD residential treatment recruited for a mindfulness-based intervention efficacy clinical trial. Participants diagnosed with PTSD (n = 14) or not (n = 29) performed a task which involved attending to the somatic and visceral sensations of the breathing cycle (interoception) while undergoing a functional MRI (fMRI) scan. FMRI analysis employed independent components analysis and dual regression. First, we assessed differences in functional connectivity of interoception-modulated functional networks among those with and without PTSD. Second, we tested associations between network strength and lifetime sexual violence exposure across all participants on networks that showed significant group differences.

RESULTS

PTSD diagnosis was associated with reduced functional connectivity of an orbitofrontal network with the precuneus, mid-posterior insula, lateral prefrontal cortex and angular gyrus. OFC network strength was inversely associated with sexual violence exposure over-and-above the contribution of PTSD status alone.

CONCLUSIONS

Our findings provide a novel network-level account of brain activity associated with PTSD among women with SUDs, which may inform treatment response in this subpopulation.

Gambling disorder

Gambling disorder is characterized by a persistent, recurrent pattern of gambling that is associated with substantial distress or impairment. The prevalence of gambling disorder has been estimated at 0.5% of the adult population in the United States, with comparable or slightly higher estimates in other countries. The aetiology of gambling disorder is complex, with implicated genetic and environmental factors. Neurobiological studies have implicated cortico-striato-limbic structures and circuits in the pathophysiology of this disorder. Individuals with gambling disorder often go unrecognized and untreated, including within clinical settings. Gambling disorder frequently co-occurs with other conditions, particularly other psychiatric disorders. Behavioural interventions, particularly cognitive-behavioural therapy but also motivational interviewing and Gamblers Anonymous, are supported in the treatment of gambling disorder. No pharmacological therapy has a formal indication for the treatment of gambling disorder, although placebo-controlled trials suggest that some medications, such as opioid-receptor antagonists, may be helpful. Given the associations with poor quality of life and suicide, improved identification, prevention, policy and treatment efforts are needed to help people with gambling disorder.

Altered interoceptive processing in smokers: Evidence from the heartbeat tracking task

Neuroimaging evidence suggests that interoceptive processing might be altered in nicotine addiction, however this has not yet been confirmed with behavioural measures. Therefore, we investigated the perception of internal bodily states in smokers (n = 49) and people who had never smoked (n = 51), by measuring interoceptive accuracy (IAcc) and interoceptive sensibility (IS). IAcc was measured with a heartbeat tracking task and a heartbeat discrimination task. Performance on the heartbeat tracking task may be influenced by one's ability to estimate an elapsed time interval so this was controlled by also administering a time-estimation (TE) task. IS was measured using two sub-scales from the Multidimensional Assessment of Interoceptive Awareness (MAIA). All smokers completed the Revised Fagerström Test for Nicotine Dependence (FTND-R) to measure addiction severity. Non-smokers performed significantly better than smokers on the heartbeat tracking task. There were no significant group differences observed for the remaining variables. Furthermore, none of the variables predicted addiction severity. This is the first demonstration of behavioural differences in interoception between smokers and non-smokers.

The Role of Language in Alexithymia: Moving Towards a Multiroute Model of Alexithymia

Alexithymia is characterized by difficulty identifying and describing one’s own emotion. Identifying and describing one’s emotion involves several cognitive processes, so alexithymia may result from a number of impairments. Here we propose the alexithymia language hypothesis—the hypothesis that language impairment can give rise to alexithymia—and critically review relevant evidence from healthy populations, developmental disorders, adult-onset illness, and acquired brain injury. We conclude that the available evidence is supportive of the alexithymia–language hypothesis, and therefore that language impairment may represent one of multiple routes to alexithymia. Where evidence is lacking, we outline which approaches will be useful in testing this hypothesis.

Interoceptive accuracy and interoceptive sensibility in individuals with alcohol use disorder-Different phenomena with different clinical correlations?

BACKGROUND

Interoception may contribute to substance use disorder as it relates to the body's experience of substance use or withdrawal. However, only a few studies have directly investigated associations between interoception and alcohol use. The objective of this study was to compare individuals with alcohol use disorder (AUD) and healthy controls on interoceptive sensibility and accuracy.

METHODS

The sample was comprised of two groups: individuals meeting criteria for AUD (N = 114) and healthy controls (N = 110) not meeting criteria for AUD. Interoceptive sensibility was assessed with a self-report measure (the Private Body Consciousness subscale) and interoceptive accuracy - with a behavioral measure (the Schandry test). In addition, associations between interoception and other well-recognized correlates of AUD (sleep problems, depressive and anxiety symptoms, impulsivity) were tested. Barratt's Impulsiveness Scale, Brief Symptom Inventory, and Athens Insomnia Scale were utilized to assess psychopathological symptoms as covariates.

RESULTS

When controlling for level of anxiety, sleep problems, age, sex and education, individuals with AUD scored significantly higher on self-reported interoceptive sensibility and lower on interoceptive accuracy in comparison to healthy controls. Higher interoceptive sensibility was associated with more severe sleep problems and anxiety symptoms.

CONCLUSIONS

These results have to be treated as preliminary and need to be replicated; however, findings indicate that interoception may present a novel therapeutic target for treatment of AUD.

Longitudinal effects of interoceptive awareness training through mindful awareness in body-oriented therapy (MABT) as an adjunct to women's substance use disorder treatment: A randomized controlled trial

BACKGROUND

Training in interoceptive awareness is a promising behavioral approach for improving substance use disorder (SUD) treatment. This study examined the longitudinal effects of Mindful Awareness in Body-oriented Therapy (MABT) as an adjunct to women's SUD treatment. MABT teaches interoceptive awareness skills to promote self-care and emotion regulation.

METHODS

Women in intensive outpatient treatment for SUD at three community clinics were recruited and randomly assigned to one of three study conditions Treatment as Usual (TAU) + MABT, TAU + Women's Health Education (WHE), and TAU only. Four assessments were delivered over one year (N = 187) baseline, 3, 6 and 12 months to examine primary outcome of percent days abstinent from substance use, and secondary outcomes of emotion dysregulation, craving, psychological distress, mindfulness and interoceptive awareness. Changes in outcomes across time were assessed using multilevel mixed effects linear regression.

RESULTS

Substance use improved significantly for MABT vs. TAU at 6 months and 12 months. Positive longitudinal effects on secondary outcomes for MABT were evident on respiratory sinus arrhythmia (RSA), a physiological index of emotion regulation; on craving; and on interoceptive awareness skills. Analyses based on participants who completed >75% of the intervention sessions revealed additional immediate significant improvements for MABT vs. TAU and WHE on depressive symptoms and emotion regulation difficulties and longitudinal improvement on mindfulness skills.

CONCLUSIONS

Results show MABT to be efficacious for longitudinal health outcomes to support women's recovery as an adjunct to community-based SUD treatment.

Dispositional use of emotion regulation strategies and resting-state cortico-limbic functional connectivity

Neuroimaging functional connectivity (FC) analyses have shown that the negative coupling between the amygdala and cortical regions is linked to better emotion regulation in experimental settings. Nevertheless, no studies have examined the association between resting-state cortico-amygdalar FC and the dispositional use of emotion regulation strategies. We aim at assessing the relationship between the resting-state FC patterns of two different amygdala territories, with different functions in the emotion response process, and trait-like measures of cognitive reappraisal and expressive suppression. Forty-eight healthy controls completed the Emotion Regulation Questionnaire (ERQ) and underwent a resting-state functional magnetic resonance imaging acquisition. FC maps of basolateral and centromedial amygdala (BLA/CMA) with different cortical areas were estimated with a seed-based approach, and were then correlated with reappraisal and suppression scores from the ERQ. FC between left BLA and left insula and right BLA and the supplementary motor area (SMA) correlated inversely with reappraisal scores. Conversely, FC between left BLA and the dorsal anterior cingulate cortex correlated directly with suppression scores. Finally, FC between left CMA and the SMA was inversely correlated with suppression. Top-down regulation from the SMA seems to account for the dispositional use of both reappraisal and suppression depending on the specific amygdala nucleus being modulated. In addition, modulation of amygdala activity from cingulate and insular cortices seem to also account for the habitual use of the different emotion regulation strategies.

Direct and indirect effects of age on interoceptive accuracy and awareness across the adult lifespan

Various aspects of physical and mental health have been linked to an individual’s ability to perceive the physical condition of their body (‘interoception’). In addition, numerous studies have demonstrated a role for interoception in higher-order cognitive abilities such as decision-making and emotion processing. The importance of interoception for health and typical cognitive functioning has prompted interest in how interoception varies over the lifespan. However, few studies have investigated interoception into older adulthood, and no studies account for the set of physiological changes that may influence task performance. The present study examined interoception from young to very late adulthood (until 90 years of age) utilising a self-report measure of interoception (Study One) and an objective measure of cardiac interoception (Study Two). Across both studies, interoception decreased with age, and changes in interoceptive accuracy were observed which were not explained by accompanying physiological changes. In addition to a direct effect of age on interoception, an indirect effect of ageing on cardiac interoceptive accuracy mediated by body mass index (BMI) was found, such that ageing was associated with increased BMI which was, in turn, associated with reduced interoceptive accuracy. Such findings support and extend previous research demonstrating interoceptive decline with advancing age, and highlight the importance of assessing whether decreasing interoceptive ability is responsible for some aspects of age-related ill-health and cognitive impairment.

Intrinsic functional and structural connectivity of emotion regulation networks in obsessive-compulsive disorder

Despite emotion regulation being altered in patients with obsessive-compulsive disorder (OCD), no studies have investigated its relation to multimodal amygdala connectivity. We compared corticolimbic functional and structural connectivity between OCD patients and healthy controls (HCs), and correlated this with the dispositional use of emotion regulation strategies and with OCD severity. OCD patients (n = 73) and HCs (n = 42) were assessed for suppression and reappraisal strategies using the Emotion Regulation Questionnaire (ERQ) and for OCD severity using the Yale-Brown Obsessive-Compulsive Scale. Resting-state functional magnetic resonance imaging (rs-fMRI) connectivity maps were generated using subject-specific left amygdala (LA) and right amygdala (RA) masks. We identified between-group differences in amygdala whole-brain connectivity, and evaluated the moderating effect of ERQ strategies. Significant regions and amygdala seeds were used as targets in probabilistic tractography analysis. Patients scored higher in suppression and lower in reappraisal. We observed higher rs-fMRI RA-right postcentral gyrus (PCG) connectivity in HC, and in patients this was correlated with symptom severity. Reappraisal scores were associated with higher negative LA-left insula connectivity in HC, and suppression scores were negatively associated with LA-precuneus and angular gyri connectivity in OCD. Structurally, patients showed higher mean diffusivity in tracts connecting the amygdala with the other targets. RA-PCG connectivity is diminished in patients, while disrupted emotion regulation is related to altered amygdala connectivity with the insula and posterior brain regions. Our results are the first showing, from a multimodal perspective, the association between amygdala connectivity and specific emotional processing domains, emphasizing the importance of amygdala connectivity in OCD pathophysiology.

Forging Neuroimaging Targets for Recovery in Opioid Use Disorder

The United States is in the midst of an opioid epidemic and lacks a range of successful interventions to reduce this public health burden. Many individuals with opioid use disorder (OUD) consume drugs to relieve physical and/or emotional pain, a pattern that may increasingly result in death. The field of addiction research lacks a comprehensive understanding of physiological and neural mechanisms instantiating this cycle of Negative Reinforcement in OUD, resulting in limited interventions that successfully promote abstinence and recovery. Given the urgency of the opioid crisis, the present review highlights faulty brain circuitry and processes associated with OUD within the context of the Three-Stage Model of Addiction (1). This model underscores Negative Reinforcement processes as crucial to the maintenance and exacerbation of chronic substance use together with Binge/Intoxication and Preoccupation/Anticipation processes. This review focuses on cross-sectional as well as longitudinal studies of relapse and treatment outcome that employ magnetic resonance imaging (MRI), functional near-infrared spectroscopy (fNIRs), brain stimulation methods, and/or electroencephalography (EEG) explored in frequency and time domains (the latter measured by event-related potentials, or ERPs). We discuss strengths and limitations of this neuroimaging work with respect to study design and individual differences that may influence interpretation of findings (e.g., opioid use chronicity/recency, comorbid symptoms, and biological sex). Lastly, we translate gaps in the OUD literature, particularly with respect to Negative Reinforcement processes, into future research directions involving operant and classical conditioning involving aversion/stress. Overall, opioid-related stimuli may lessen their hold on frontocingulate mechanisms implicated in Preoccupation/Anticipation as a function of prolonged abstinence and that degree of frontocingulate impairment may predict treatment outcome. In addition, longitudinal studies suggest that brain stimulation/drug treatments and prolonged abstinence can change brain responses during Negative Reinforcement and Preoccupation/Anticipation to reduce salience of drug cues, which may attenuate further craving and relapse. Incorporating this neuroscience-derived knowledge with the Three-Stage Model of Addiction may offer a useful plan for delineating specific neurobiological targets for OUD treatment.

A Roadmap for Integrating Neuroscience Into Addiction Treatment: A Consensus of the Neuroscience Interest Group of the International Society of Addiction Medicine

Although there is general consensus that altered brain structure and function underpins addictive disorders, clinicians working in addiction treatment rarely incorporate neuroscience-informed approaches into their practice. We recently launched the Neuroscience Interest Group within the International Society of Addiction Medicine (ISAM-NIG) to promote initiatives to bridge this gap. This article summarizes the ISAM-NIG key priorities and strategies to achieve implementation of addiction neuroscience knowledge and tools for the assessment and treatment of substance use disorders. We cover two assessment areas: cognitive assessment and neuroimaging, and two interventional areas: cognitive training/remediation and neuromodulation, where we identify key challenges and proposed solutions. We reason that incorporating cognitive assessment into clinical settings requires the identification of constructs that predict meaningful clinical outcomes. Other requirements are the development of measures that are easily-administered, reliable, and ecologically-valid. Translation of neuroimaging techniques requires the development of diagnostic and prognostic biomarkers and testing the cost-effectiveness of these biomarkers in individualized prediction algorithms for relapse prevention and treatment selection. Integration of cognitive assessments with neuroimaging can provide multilevel targets including neural, cognitive, and behavioral outcomes for neuroscience-informed interventions. Application of neuroscience-informed interventions including cognitive training/remediation and neuromodulation requires clear pathways to design treatments based on multilevel targets, additional evidence from randomized trials and subsequent clinical implementation, including evaluation of cost-effectiveness. We propose to address these challenges by promoting international collaboration between researchers and clinicians, developing harmonized protocols and data management systems, and prioritizing multi-site research that focuses on improving clinical outcomes.

The effect of passive heat stress on distress andself-control in male smokers and non-smokers

In the current study, we tested the effects of core body temperature increases (e.g. heat stress) on affect, self-reported physical discomfort, and subsequent self-control in male smokers and nonsmokers using a novel passive heat stress paradigm, within a distress tolerance framework. Twenty-eight men (14 smokers), completed both heat stress and control sessions in randomized order. Results revealed that increases in core body temperature were associated with increased anxiety, irritability, and body discomfort as well as decreased happiness, with stronger effects for smokers. Smokers and nonsmokers both evidenced less self-control during the heat session and did not differ on this measure, nor on a measure of interoceptive sensitivity. The current study indicates that heat stress is a viable method for studying distress tolerance in men, and suggests the value in examining dynamic changes in self-control as a function of distress. Implications will be discussed for distress tolerance in general and smokers in specific.

Let's Open the Decision-Making Umbrella: A Framework for Conceptualizing and Assessing Features of Impaired Decision Making in Addiction

Decision-making impairments play a pivotal role in the emergence and maintenance of addictive disorders. However, a sound conceptualization of decision making as an umbrella construct, encompassing its cognitive, affective, motivational, and physiological subcomponents, is still lacking. This prevents an efficient evaluation of the heterogeneity of decision-making impairments and the development of tailored treatment. This paper thus unfolds the various processes involved in decision making by adopting a critical approach of prominent dual- or triadic-process models, which postulate that decision making is influenced by the interplay of impulsive-automatic, reflective-controlled, and interoceptive processes. Our approach also focuses on social cognition processes, which play a crucial role in decision making and addictive disorders but were largely ignored in previous dual- or triadic-process models. We propose here a theoretical framework in which a range of coordinated processes are first identified on the basis of their theoretical and clinical relevance. Each selected process is then defined before reviewing available results underlining its role in addictive disorders (i.e., substance use, gambling, and gaming disorders). Laboratory tasks for measuring each process are also proposed, initiating a preliminary process-based decision-making assessment battery. This original approach may offer an especially informative view of the constitutive features of decision-making impairments in addiction. As prior research has implicated these features as risk factors for the development and maintenance of addictive disorders, our processual approach sets the scene for novel and transdiagnostic experimental and applied research avenues.

Immediate effects of interoceptive awareness training through Mindful Awareness in Body-oriented Therapy (MABT) for women in substance use disorder treatment

Background: Sensory information gained through interoceptive awareness may play an important role in affective behavior and successful inhibition of drug use. This study examined the immediate pre-post effects of the mind-body intervention Mindful Awareness in Body-oriented Therapy (MABT) as an adjunct to women's substance use disorder (SUD) treatment. MABT teaches interoceptive awareness skills to promote self-care and emotion regulation. Methods: Women in intensive outpatient treatment (IOP) for chemical dependency (N = 217) at 3 community clinics in the Pacific Northwest of the United States were recruited and randomly assigned to one of 3 study conditions: MABT + treatment as usual (TAU), women's health education (WHE) +TAU (active control condition), and TAU only. At baseline and 3 months post-intervention, assessments were made of interoceptive awareness skills and mindfulness, emotion regulation (self-report and psychophysiological measures), symptomatic distress (depression and trauma-related symptoms), and substance use (days abstinent) and craving. Changes in outcomes across time were assessed using multilevel mixed-effects linear regression. Results: Findings based on an intent-to-treat approach demonstrated significant improvements in interoceptive awareness and mindfulness skills, emotion dysregulation (self-report and psychophysiology), and days abstinent for women who received MABT compared with the other study groups. Additional analyses based on participants who completed the major components of MABT (at least 75% of the intervention sessions) revealed these same improvements as well as reductions in depressive symptoms and substance craving. Conclusions: Findings that interoceptive training is associated with health outcomes for women in SUD treatment are consistent with emerging neurocognitive models that link interoception to emotion regulation and to related health outcomes, providing knowledge critical to supporting and improving SUD treatment.

Metabotropic Glutamate Receptors in Alcohol Use Disorder: Physiology, Plasticity, and Promising Pharmacotherapies

Developing efficacious treatments for alcohol use disorder (AUD) has proven difficult. The insidious nature of the disease necessitates a deep understanding of its underlying biology as well as innovative approaches to ameliorate ethanol-related pathophysiology. Excessive ethanol seeking and relapse are generated by long-term changes to membrane properties, synaptic physiology, and plasticity throughout the limbic system and associated brain structures. Each of these factors can be modulated by metabotropic glutamate (mGlu) receptors, a diverse set of G protein-coupled receptors highly expressed throughout the central nervous system. Here, we discuss how different components of the mGlu receptor family modulate neurotransmission in the limbic system and other brain regions involved in AUD etiology. We then describe how these processes are dysregulated following ethanol exposure and speculate about how mGlu receptor modulation might restore such pathophysiological changes. To that end, we detail the current understanding of the behavioral pharmacology of mGlu receptor-directed drug-like molecules in animal models of AUD. Together, this review highlights the prominent position of the mGlu receptor system in the pathophysiology of AUD and provides encouragement that several classes of mGlu receptor modulators may be translated as viable treatment options.

Alexithymia mediates the relationship between interoceptive sensibility and anxiety

A number of empirical and theoretical reports link altered interoceptive processing to anxiety. However, the mechanistic understanding of the relationship between the two remains poor. We propose that a heightened sensibility for interoceptive signals, combined with a difficulty in attributing these sensations to emotions, increases an individual’s vulnerability to anxiety. In order to investigate this, a large sample of general population adults were recruited and completed self-report measures of interoceptive sensibility, trait anxiety and alexithymia. Results confirmed that the positive association between interoceptive sensibility and trait anxiety was partially mediated by alexithymia, such that those most at risk for clinically significant levels of trait anxiety have both significantly higher levels of interoceptive sensibility and alexithymia. A subsequent factor analysis confirmed the independence of the three measures. Altered interoceptive processing in combination with alexithymia, increased the risk for anxiety above and beyond altered interoceptive processing alone. We suggest that a heightened sensibility for interoceptive signals, combined with a difficulty in attributing these sensations to emotions, leaves these sensations vulnerable to catastrophizing interpretation. Interventions that target the attribution of bodily sensations may prove valuable in reducing anxiety.