Objective and subjective measurement of sleep in people who use substances: Emerging evidence and recommendations from a systematic review.

People who use substances commonly experience sleep disruptions, affecting the regulation of physical and mental health, and presenting a significant barrier to treatment success. Sleep impairments are noted in all phases of substance use; however, differences between subjective versus objective methods used to measure sleep quality have been reported. While polysomnography is the gold-standard for sleep measurement, recent advances in actigraphy may help address the discordance between subjective and objective sleep reports. This systematic review examined emerging evidence (2016-present) for sleep impairment in people who use substances, with the twofold goal of: (1) identifying whether sleep outcomes vary across substance type (alcohol, nicotine, cannabis, cocaine, methamphetamine and opioids); and (2) contrasting results from subjective and objective measures. While some differences between subjective and objective sleep were noted, there was overwhelming evidence of clinically relevant sleep impairment in people who use alcohol, nicotine, cocaine, methamphetamine and opioids, with less consistent results for cannabis. Gaps in the literature are identified and future recommendations are presented, including utilization of common methodological frameworks, identification of mechanisms, and closer examination of sleep across stages of substance use and the interconnection between sleep and return to use.

A meta-analysis of electrophysiological biomarkers of reward and error monitoring in substance misuse.

Substance use disorders are characterized by marked changes in reward and error processing. The primary objective of this meta-analysis was to estimate effect sizes for the reward positivity (RewP) and error-related negativity (ERN), two event-related potential indicators of outcome monitoring, in substance users compared to controls. The secondary objective was to test for moderation by demographic, substance type, and EEG experiment parameters. Final PubMed searches were performed in August 2023. Inclusion criteria were substance use disorder/dependence or validated self-report of substance misuse, RewP/ERN means available, healthy control comparison group, non-acute drug study, peer-reviewed journal, English language, and human participants. Selection bias was tested through modified Egger's regression and exploratory 3-parameter selection model tests. The RewP results (19 studies, 1641 participants) did not support an overall effect (Hedges' g = 0.07, 95% CI [-0.44, 0.58], p = .777) and nor effect of any moderators. The ERN results (20 studies, 1022 participants) indicated no significant overall effect (g = 0.41, 95%CI [-0.05, 0.88]). Subgroup analyses indicated that cocaine users had a blunted ERN compared to controls (g = 1.12, 95%CI [0.77, 1.47]). There was limited evidence for publication/small study bias. Although the results indicate a potential dissociation between substance types, this meta-analysis revealed the need for additional research on the RewP/ERN in substance using populations and for better designed experiments that adequately address research questions.

Distress tolerance: prospective associations with cognitive-behavioral therapy outcomes in adults with posttraumatic stress and substance use disorders.

74Distress tolerance (DT; perceived or actual ability to tolerate aversive physical or emotional states) is related to both posttraumatic stress disorder (PTSD) symptoms and substance use disorders (SUD). This investigation evaluates self-report and behavioral measures of DT as potential predictors of PTSD and SUD cognitive-behavioral therapy outcomes. Participants included 41 treatment-seeking adults (53.7% women; 73.2% African American; Mage = 44.90, SD = 9.68) who met at least four symptoms of DSM-5 PTSD and DSM-IV substance dependence, assessed via structured interviews. At baseline (pre-treatment), participants completed the Distress Tolerance Scale (DTS), Mirror-Tracing Persistence Task (MTPT), Breath Holding task, and Paced Auditory Serial Addition Task. The Clinician-Administered PTSD Scale for DSM-5 severity scores and percent days of primary substance use, measured via Timeline Follow-back, were used as indicators of PTSD symptoms and substance use, respectively. Covariates included treatment condition, baseline PTSD symptom severity, and baseline substance use. Lower perceived DT at baseline (DTS total score) was associated with higher PTSD symptom severity at end-of-treatment. Lower behavioral DT at baseline (MTPT duration) was associated with higher substance use at the conclusion of treatment (i.e. proportion of number of use days to total number of days between two final treatment sessions).

Initial development of a brief assessment of cocaine demand.

Cocaine demand is a behavioral economic measure assessing drug reward value and motivation to use drug. The purpose of the current study was to develop a brief assessment of cocaine demand (BACD). Results from the BACD were compared with self-report measures of cocaine use. Participants consisted of treatment-seeking individuals with cocaine use disorder (N = 22). Results revealed that indices of brief demand were significantly associated with various self-report measures of cocaine use. Overall, these results support the utility of a BACD for assessing cocaine demand.

Exenatide Adjunct to Nicotine Patch Facilitates Smoking Cessation and May Reduce Post-Cessation Weight Gain: A Pilot Randomized Controlled Trial.

INTRODUCTION: Approved pharmacological treatments for smoking cessation are modestly effective, underscoring the need for improved pharmacotherapies. Glucagon-like peptide-1 receptor (GLP-1R) agonists attenuate the rewarding effects of nicotine in preclinical studies. We examined the efficacy of extended-release exenatide, a GLP-1R agonist, combined with nicotine replacement therapy (NRT, patch) for smoking cessation, craving, and withdrawal symptoms, with post-cessation body weight as a secondary outcome. METHODS: Eighty-four prediabetic and/or overweight smokers were randomized (1 : 1) to once-weekly placebo or exenatide, 2 mg, subcutaneously. All participants received NRT (21 mg) and brief smoking cessation counseling. Seven-day point prevalence abstinence (expired CO level ≤5 ppm), craving, withdrawal, and post-cessation body weight were assessed following 6 weeks of treatment. A Bayesian approach for analyzing generalized linear models yielded posterior probabilities (PP) to quantify the evidence favoring hypothesized effects of treatment on the study outcomes. RESULTS: Exenatide increased the risk for smoking abstinence compared to placebo (46.3% and 26.8%, respectively), (risk ratio [RR] = 1.70; 95% credible interval = [0.96, 3.27]; PP = 96.5%). Exenatide reduced end-of-treatment craving in the overall sample and withdrawal among abstainers. Post-cessation body weight was 5.6 pounds lower in the exenatide group compared to placebo (PP = 97.4%). Adverse events were reported in 9.5% and 2.3% of participants in the exenatide and placebo groups, respectively. CONCLUSIONS: Exenatide, in combination with the NRT improved smoking abstinence, reduced craving and withdrawal symptoms, and decreased weight gain among abstainers. Findings suggest that the GLP-1R agonist strategy is worthy of further research in larger, longer duration studies. IMPLICATIONS: Despite considerable progress in tobacco control, cigarette smoking remains the leading cause of preventable disease, disability, and death. In this pilot study, we showed that extended-release exenatide, a glucagon-like peptide-1 receptor agonist, added to the nicotine patch, improved abstinence and mitigated post-cessation body weight gain compared to patch alone. Further research is needed to confirm these initial positive results.

A meta-analysis of tract-based spatial statistics studies examining white matter integrity in cocaine use disorder.

Tract-based spatial statistics (TBSS) of diffusion tensor imaging (DTI) studies have consistently shown diminished white matter (WM) integrity for individuals with cocaine use disorder (CUD). The present study used seed-based d mapping (SDM) to determine the extent to which a systematic difference in the WM integrity of cocaine users may exist (as compared with that of healthy controls). Articles from 2006 (when TBSS was first developed) to present were reviewed, with eight selected for inclusion. Meta-analysis found lower fractional anisotropy (FA) in the genu of the corpus callosum for cocaine users, with a small-to-moderate peak effect size (Hedge's g = -0.331). Sensitivity analyses mostly supported the robustness of the obtained difference. Differences detected at exploratory thresholds for significance suggested insult to WM integrity extending beyond the corpus callosum. The present results compliment a previous region-of-interest (ROI)-based meta-analysis of DTI studies in individuals with CUD. These findings have significant implications for the potential role of neuroprotective agents in the treatment of CUD and merit additional iteration as more studies accrue in the literature.

Plasma pro- and anti-inflammatory cytokines may relate to cocaine use, cognitive functioning, and depressive symptoms in cocaine use disorder.

BACKGROUND: Inflammation is implicated in cocaine use and associated problems, including depression and cognitive impairment. OBJECTIVE: We assessed 18 cytokines, cocaine use, cognition, and depression in individuals with Cocaine Use Disorder. Our general hypothesis was that higher pro-inflammatory cytokines would relate to more cocaine use, poorer cognition, and more depression, while higher anti-inflammatory cytokines would relate to less cocaine use, better cognition, and less depression. METHODS: Data were collected from 85 individuals (76.5% male, 80% African American) aged 18-65. The ASI, Shipley-2, and BDI-II assessed frequency and duration of cocaine use, cognition, and depression. Cytokines were tested using Bio-Plex Pro™ assays. Elastic net regression identified which cytokines related to each measure, controlling for confounds. RESULTS: Lower IL-29 (B = -0.08, bootstrapped 95%CI = [-0.24,0.07]), scD163 (B = -0.11, bootstrapped 95%CI = [-0.27,0.04]), Eotaxin-1 CCL11 (B = -0.11, bootstrapped 95%CI = [-0.30,0.08]), and higher APRIL/TNFSF13 (B = 0.11, bootstrapped 95%CI = [-0.08,0.30]) related to more frequent cocaine use. Lower IL-29 (B = -0.24, bootstrapped 95% CI = [-2.26,1.79]) and IL-20 (B = -1.62, bootstrapped 95%CI = [-3.53,0.29]) related to longer duration of cocaine use. Higher Eotaxin-2 CCL24 (B = 2.79, bootstrapped 95%CI = [-0.59,6.17]) and TWEAK (B = 2.83, bootstrapped 95%CI = [-0.80,6.45]) related to better cognition. Finally, higher IL-20 (B = -1.83, bootstrapped 95%CI = [-3.70,0.04]) and Osteocalcin (B = -1.56, bootstrapped 95%CI = [-3.81,0.70]) related to lower depressive symptoms. However, none of these relationships survived bootstrapped analyses. CONCLUSION: Pro- and anti-inflammatory cytokines may relate to cocaine use, cognition, and depression, but inconsistent with our hypotheses, higher pro-inflammatory cytokines related to better functioning in several domains. Additionally, cytokines were selected at low frequencies and demonstrated weak relationships with outcomes. These preliminary findings suggest complex relationships between inflammation and cocaine use.

Equal response rates maintained by concurrent drug and nondrug reinforcers: a design for treatment evaluation.

During daily 3-h sessions, four rhesus monkeys had concurrent access to 16% alcohol (w/v) and saccharin. A response occurred when a monkey made mouth contact with the metal spout and thereby completed a drinkometer circuit. The liquids were available under concurrent nonindependent fixed-ratio 32 schedules. With these schedules, responses on the right spout decremented both the right and left fixed-ratio counters and vice versa. Responding was well maintained by both alcohol and saccharin. Increases in saccharin concentration produced increases in saccharin responding to the point that saccharin responding exceeded alcohol responding. Responses per saccharin delivery were also a direct function of the saccharin concentration. In contrast, responses per alcohol delivery generally decreased as the saccharin concentration became greater. Changeover or switching responses were also a direct function of the saccharin concentration. Relative reinforcing effects of each combination of liquid pairs were measured for each monkey. For all monkeys, it was possible to establish equal rates of responding for both reinforcers and frequent switching between reinforcers. The balanced responding can serve as a baseline for the evaluation of potential treatments that may alter relative reinforcing effects.

Resting Heart Rate Variability: Exploring Associations With Symptom Severity in Adults With Substance Use Disorders and Posttraumatic Stress.

Objective: Substance use disorders and posttraumatic stress symptoms are commonly comorbid. Previous studies have established that those with substance use disorders or posttraumatic stress disorder (PTSD) have lower high frequency-heart rate variability (HF-HRV) compared to controls, suggesting that low HF-HRV may be a biomarker of a common physiological mechanism underlying both disorders. We evaluated HF-HRV as a potential biomarker of a common underlying process by testing whether lower HF-HRV related to greater severity of substance use and PTSD symptoms in individuals with both substance use disorders and at least four symptoms of PTSD. Methods: HF-HRV was measured in 49 adults with substance use disorders and at least four symptoms of PTSD. We performed a series of regressions controlling for age to test whether low HF-HRV was associated with greater substance use disorder and PTSD symptom severity. Substance use disorder symptoms were measured by the Addiction Severity Index and PTSD symptoms were measured by the Clinician-Administered PTSD Scale and the PTSD Checklist. Results: After controlling for age, low resting HF-HRV was significantly associated with drug and alcohol symptom severity but not PTSD symptom severity. Conclusions: HF-HRV may be more sensitive to the severity of drug and alcohol use rather than PTSD. Findings may suggest that in PTSD populations, HF-HRV may primarily index comorbid substance use disorder symptoms. HF-HRV could serve as an objective measure of substance use severity and should be further investigated as a predictor of outcomes in treatment for substance use disorders.

The impact of substance use disorders on clinical outcomes in older-adult psychiatric inpatients.

OBJECTIVE: To examine associations among substance use disorder (SUD) and measures of length of stay (LOS) and non-psychiatric medical comorbidity (MEDCO) in older-adult inpatients with serious mental illness (SMI), hypothesizing SUD would be related to worse clinical outcomes. METHODS: A cross-sectional study analyzed medical records from 2010 to 2016 of 7258 inpatients with SMI ≥ age 50, obtained from a 274-bed psychiatric hospital. Descriptive analyses examined prevalence rates for SUD status (+/-), individual drug classes, and total number of SUDs (polysubstance use disorders). Regression models examined the influence of 2 independent variables of interest: (1) SUD status (+/-) and (2) type of SUD (ie, specific drug), controlling for demographic factors and additional (non-SUD) psychiatric disorders. Two dependent (outcome) variables were examined: LOS and MEDCO. RESULTS: The overall SUD rate was 26%; cocaine was the most common SUD (≈ 10%). SUD status and additional (non-SUD) psychiatric diagnoses were significantly associated with longer LOS (both P < 0.001). For individual SUDs, cocaine, marijuana, opiates, and alcohol were all significantly associated with LOS (all P < 0.01). SUD status, age, sex, admission status, and race were significantly associated with MEDCO (all P < 0.002). For individual SUDs, barbiturates, opiates, and alcohol were all significantly associated with MEDCO (P < 0.01). CONCLUSIONS: The prevalence of SUD in this sample underscores concerns related to treating older adults presenting providers with comorbid SUD and SMI. This combination may increase the burden and complexity of care, warranting further investigation into mechanisms and long-term consequences.

PPARγ agonism attenuates cocaine cue reactivity.

Cocaine use disorder is a chronic relapsing condition characterized by compulsive drug seeking and taking even after prolonged abstinence periods. Subsequent exposure to drug-associated cues can promote intense craving and lead to relapse in abstinent humans and rodent models. The responsiveness to these cocaine-related cues, or 'cue reactivity', can trigger relapse and cocaine-seeking behaviors; cue reactivity is measurable in cocaine-dependent humans as well as rodent models. Cue reactivity is thought to be predictive of cocaine craving and relapse. Here we report that PPARγ agonism during abstinence from cocaine self-administration reduced previously active lever pressing in Sprague Dawley rats during cue-reactivity tests, while administration of the PPARγ antagonist, GW9662, reversed this effect. PPARγ agonism also normalized nuclear ERK activity in the medial prefrontal cortex and hippocampus which was reversed with GW9662. Our results support the utility of PPARγ agonism as a relapse prevention strategy to maintain abstinence in the presence of cocaine-associated cues.

Heightened early-attentional stimulus orienting and impulsive action in men with antisocial personality disorder.

We tested whether enhanced stimulus orienting operationalized as N1 and P2 auditory evoked potentials to increasing loudness (50-90 dB clicks) could be associated with trait impulsivity (Barratt Impulsiveness Scale, BIS-11), impulsive action (commission error on the Immediate Memory Task), or impulsive choice (immediate responses on temporal discounting tasks). We measured N1 and P2 loudness sensitivity in a passive listening task as linear intensity-sensitivity slopes in 36 men with antisocial personality disorder with a history of conviction for criminal conduct and 16 healthy control men. Across all subjects, regression analyses revealed that a steeper P2 slope predicted higher IMT commission error/correct detection ratio, and lower stimulus discriminability (A-prime). These associations were also found within both groups. These relationships suggest an association between enhanced early stimulus orienting (P2), impulsive action (response inhibition), and impaired signal-noise discriminability (A-prime).

Effects of oxytocin on aggressive responding in healthy adult men.

This study investigated the acute effects of oxytocin (OT) on human aggression using a well-established laboratory measure of state (reactive) aggression to test the hypothesis that OT would decrease the frequency of aggressive responding. In a within-subject design, 17 healthy male volunteers received placebo or 24 IU of intranasal OT. Aggression was measured using the Point Subtraction Aggression Paradigm at 30 min before and 30, 60, and 90 min after dose. Acute OT did not produce a significant main effect on aggressive behavior. OT attenuated the expected rise in diastolic blood pressure from morning to early afternoon observed under placebo, providing a possible indication of biological activity. Examination of individual differences showed that aggressive responding following OT dosing (but not placebo) was positively correlated with psychometric measures of interpersonal manipulation and anger (Pearson's r=0.57), indicating that higher scores on these antisocial personality traits were related to increased aggressive behavior following OT administration. These preliminary results stand in contrast to previous work on the prosocial effects of OT and highlight the need for further understanding of individual differences in aggression following OT administration. Such individual differences may have implications for the therapeutic use of OT in individuals with psychiatric disorders and dysfunctional social behavior.

Racial disparities during admission to an academic psychiatric hospital in a large urban area.

Multiple studies confirm that African Americans are less likely than non-Hispanic whites to receive needed mental health services. Research has consistently shown that African Americans are under-represented in outpatient mental health treatment settings and are over-represented in inpatient psychiatric settings. Further, African Americans are more likely to receive a diagnosis of schizophrenia and are less likely receive an affective disorder diagnosis during inpatient psychiatric hospitalization compared to non-Hispanic white patients, pointing to a need for examining factors contributing to mental health disparities. Using Andersen's Behavioral Model of Health Service Use, this study examined predisposing, enabling and need factors differentially associated with health service utilization among African American and non-Hispanic white patients (n=5183) during psychiatric admission. We conducted univariate and multivariate logistic regression analyses to examine both main effects and interactions. In the multivariate model, African American race at admission was predicted by multiple factors including younger age, female gender, multiple psychiatric hospitalizations, elevated positive and negative symptoms of psychosis, a diagnosis of schizophrenia and substance use, as well as having housing and commercial insurance. Additionally, screening positive for cannabis use at intake was found to moderate the relationship between being female and African American. Our study findings highlight the importance of examining mental health disparities using a conceptual framework developed for vulnerable populations (such as racial minorities and patients with co-occurring substance use).

Prevalence of traumatic brain injury in cocaine-dependent research volunteers.

BACKGROUND: There is a high prevalence of traumatic brain injury (TBI) among those with substance dependence. However, TBI often remains undiagnosed in these individuals, due to lack of routine screening in substance use treatment settings or due to overlap in some of the cognitive sequelae (eg impulsivity, disinhibition) of TBI and cocaine dependence. METHODS: The prevalence of self-reported mild to moderate TBI in a group of cocaine-dependent (n = 95) and a group of healthy volunteers (n = 75) enrolled at the same facility was assessed. Additionally, the relationship between TBI and clinically relevant correlates, including impulsivity, cocaine use history, and treatment outcome in the cocaine-dependent group was also examined. RESULTS: A higher proportion of individuals with cocaine dependence (29.5%) reported having suffered a TBI in their lifetime compared to controls (8%) on a Closed Head Injury scale. Among cocaine users, the average age of sustaining TBI was significantly lower than the age of initiating cocaine use. Presence of TBI was not associated with higher impulsivity on the Barratt Impulsiveness Scale-11 or self-reported years of cocaine use. No differences were noted on treatment outcome for cocaine dependence as measured by treatment effectiveness scores (TES) between cocaine users with TBI and their non-TBI counterparts. CONCLUSIONS: These results are the first to highlight the high prevalence of TBI among individuals with cocaine dependence. This study underscores the possible role of TBI history as a risk factor for onset of cocaine use, however, more research is needed to determine the impact of co-morbid TBI as a complicating factor in the substance abuse treatment setting.

Hospital length of stay in individuals with schizophrenia with and without cocaine-positive urine drug screens at hospital admission.

Despite the high prevalence of cocaine use disorder (CUD) in individuals with schizophrenia, current understanding of the effect of cocaine on psychiatric hospital length of stay (LOS) in individuals with schizophrenia is limited. We therefore retrospectively examined the medical records of 5106 hospital admissions due to exacerbation of schizophrenia. Linear regression and t-test were used to compare LOS between individuals with schizophrenia with cocaine-positive urine drug test results and those with negative test results. Individuals with schizophrenia who were also positive for cocaine had shorter LOS from both unadjusted (geometric mean LOS, 8.07 ± 1.92 vs. 11.83 ± 1.83 days; p < 0.001) and adjusted (ß = 0.69; confidence interval, 0.63-0.76; p < 0.001) analyses. Our results suggest that individuals with schizophrenia who also have comorbid CUD may require shorter inpatient treatment during periods of exacerbation of symptoms. Replication of this finding has relevance in treatment planning and resource allocation for the subpopulation of individuals with schizophrenia who also have stimulant use disorders.

Demographic and psychological factors associated with lifetime cocaine use: An exploratory factor analysis of baseline questionnaires.

OBJECTIVES: Underlying heterogeneity among individuals with cocaine dependence is widely postulated in the literature, however, identification of a group of factors that explain risk of cocaine use severity has yet to be confirmed. METHODS: Latent mixture modeling evaluated 338 cocaine-dependent individuals recruited from the community to assess the evidence for the presence of distinct subgroups. Variables included 5 baseline questionnaires measuring cognitive function (Shipley), impulsivity (BIS), mood (BDI), affective lability (ALS), and addiction severity (ASI). Results failed to suggest multiple subgroups. Given a lack of evidence for discrete latent classes, an exploratory factor analysis (EFA) followed by exploratory structural equation modeling (ESEM) was implemented to identify functional dimensions to enhance interpretation of these variables. RESULTS: Findings from the EFA indicated a 3-factor model as the best fit, and the subsequent ESEM solution resulted in associations with lifetime cocaine use. Factor 1, best characterized by demographic factors (gender, age), is associated with less lifetime cocaine use. Psychological problems best characterize factor 2, which is associated with higher lifetime cocaine use. Finally, factor 3 is characterized by other substance use (alcohol and marijuana). Although this factor did not demonstrate a statistically reliable relation with self-reported, lifetime cocaine use, it did indicate a potentially meaningful positive association. CONCLUSIONS: These 3 factors delineate dimensions of functioning that likewise help characterize the variability found in previously established associations with self-reported cocaine use.

Effects of Intranasal Oxytocin on Aggressive Responding in Antisocial Personality Disorder.

The oxytocin receptor is important in several domains of social behavior, and administration of oxytocin modulates social responding in several mammalian species, including humans. Oxytocin has both therapeutic and scientific potential for elucidating the neural and behavioral mechanisms governing social behavior. In the present study, operationally-defined aggressive behavior of six males with Antisocial Personality Disorder (ASPD) was measured following acute intranasal oxytocin dosing (12, 24, and 48 international units) and placebo, using a well-validated laboratory task of human aggression (Point-Subtraction Aggression Paradigm, or PSAP). The PSAP provides participants with concurrently available monetary-earning and operationally-defined aggressive response options, maintained by fixed ratio schedules of consequences. Shifts in response rates and inter-response time (IRT) distributions were observed on the aggressive response option following oxytocin doses, relative to placebo. Few changes were observed in monetary-reinforced responding. However, across participants the direction and magnitude of changes in aggressive responding were not systematically related to dose. No trends were observed between psychometric or physiological data and oxytocin dosing or aggressive behavior. While this report is to our knowledge the first to examine the acute effects of oxytocin in this population at high risk for violence and other forms of antisocial behavior, several limitations in the experimental design and the results cast the study as a preliminary report. Strategies for more extensive future projects are discussed.

The influence of dopamine ß-hydroxylase gene polymorphism rs1611115 on levodopa/carbidopa treatment for cocaine dependence: a preliminary study.

Recent studies have suggested that heterogeneity in the level of dopamine activity and function might be useful for identifying a subgroup of cocaine-dependent patients responding better to dopamine-enhancement pharmacotherapy. Here we hypothesized that response to levodopa/carbidopa treatment would be greater in patients with genetically determined low levels of the dopamine metabolizing enzyme dopamine ß-hydroxylase (DßH). Seventy-one cocaine-dependent patients who participated in a 12-week randomized double-blind placebo-controlled trial of levodopa/carbidopa were genotyped for the DßH gene (DBH) polymorphism rs1611115. Our results showed that for patients with the low DßH activity genotypes (CT/TT) who received levodopa, the odds of having cocaine-positive urine decreased significantly over treatment compared with placebo-treated patients with the CT/TT genotypes (P=0.004). Individuals with the normal DßH activity genotype (CC) showed no differential response to levodopa. These preliminary results need to be confirmed in a larger sample focusing on the DBH polymorphism.

Behavioral therapies targeting reward mechanisms in substance use disorders.

Behavioral therapies are considered best practices in the treatment of substance use disorders (SUD) and used as first-line approaches for SUDs without FDA-approved pharmacotherapies. Decades of research on the neuroscience of drug reward and addiction have informed the development of current leading behavioral therapies that, while differing in focus and technique, have in common the overarching goal of shifting reward responding away from drug and toward natural non-drug rewards. This review begins by describing key neurobiological processes of reward in addiction, followed by a description of how various behavioral therapies address specific reward processes. Based on this review, a conceptual 'map' is crafted to pinpoint gaps and areas of overlap, serving as a guide for selecting and integrating behavioral therapies.