Aimee L McRae-Clark

Medical University of South Carolina, Charleston, South Carolina, United States

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Publications (30)97.85 Total impact

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    ABSTRACT: Despite recent advances in behavioral interventions for cannabis use disorders, effect sizes remain modest, and few individuals achieve long-term abstinence. One strategy to enhance outcomes is the addition of pharmacotherapy to complement behavioral treatment, but to date no efficacious medications targeting cannabis use disorders in adults through large, randomized controlled trials have been identified. The National Institute on Drug Abuse Clinical Trials Network (NIDA CTN) is currently conducting a study to test the efficacy of N-acetylcysteine (NAC) versus placebo (PBO), added to contingency management, for cannabis cessation in adults (ages 18-50). This study was designed to replicate positive findings from a study in cannabis-dependent adolescents that found greater odds of abstinence with NAC compared to PBO. This paper describes the design and implementation of an ongoing 12-week, intent-to-treat, double-blind, randomized, placebo-controlled study with one follow-up visit four weeks post-treatment. Approximately 300 treatment-seeking cannabis-dependent adults will be randomized to NAC or PBO across six study sites in the United States. The primary objective of this 12-week study is to evaluate the efficacy of twice-daily orally-administered NAC (1200mg) versus matched PBO, added to contingency management, on cannabis abstinence. NAC is among the first medications to demonstrate increased odds of abstinence in a randomized controlled study among cannabis users in any age group. The current study will assess the cannabis cessation efficacy of NAC combined with a behavioral intervention in adults, providing a novel and timely contribution to the evidence base for the treatment of cannabis use disorders.
    Contemporary clinical trials. 08/2014;
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    ABSTRACT: Abstract Background: Stress and drug-paired cues increase drug craving and noradrenergic activity in cocaine-dependent individuals. Thus, medications that attenuate noradrenergic activity may be effective therapeutic treatment options for cocaine-dependent individuals. Objectives: To examine the impact of acute administration of the α2 adrenergic receptor agonist guanfacine on responses to multiple risk factors for relapse in cocaine-dependent individuals. Methods: In a double-blind, placebo-controlled study, cocaine-dependent individuals (n = 84), were randomized to receive either 2 mg guanfacine (n = 50) or placebo (n = 34). Within each treatment arm, subjects were randomized to either a stress (guanfacine n = 26; placebo n = 15) or a no-stress (guanfacine n = 24; placebo n = 19) group. Participants in the stress group performed the Trier Social Stress Test. Subjects in each group were exposed to a neutral cue and then to cocaine-related cues. Plasma cortisol and subjective responses were compared between the four groups. Results: The no-stress guanfacine group reported greater craving in response to cocaine cues as compared to the neutral cue (p < 0.001). The guanfacine stress group reported greater subjective stress at the neutral cue than at baseline (p = 0.032). The cocaine cue increased subjective stress in the guanfacine (p < 0.001) no-stress group. There were no effects of guanfacine on cortisol levels in either the stress or no stress groups (all p > 0.70). Conclusion: This study found no effects of a single 2 mg dose of guanfacine on reactivity to stress and cues alone or on the interaction of stress and drug cues. In cocaine-dependent individuals an acute 2 mg dose of guanfacine may not be an effective therapeutic treatment strategy.
    The American Journal of Drug and Alcohol Abuse 08/2014; · 1.55 Impact Factor
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    ABSTRACT: Functional Magnetic Resonance Imaging research has attempted to elucidate the neurobehavioral underpinnings of cocaine dependence by evaluating differences in brain activation to cocaine and response inhibition cues between cocaine dependent individuals and controls. This study investigated associations between task-related brain activation and cocaine use characteristics.
    Addiction 06/2014; · 4.58 Impact Factor
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    ABSTRACT: Preclinical studies suggest that stress potentiates cue-induced cocaine seeking and that this effect is more pronounced in females. These findings have not been characterized in clinical populations. The objectives of this study were to examine the impact a pharmacological stressor, alpha-2 adrenergic receptor antagonist yohimbine, on the subjective, endocrine, and physiologic responses to drug-paired cues cocaine-dependent men and women. In a double-blind placebo-controlled cross-over study, cocaine-dependent men (n = 32), cocaine-dependent women (n = 30), control men (n = 32), and control women (n = 25) received either yohimbine or placebo prior to two cocaine cue exposure sessions. Yohimbine increased ratings of anxiety both before (p < 0.001) and after (p = 0.035) cues, and the post-cue increase in anxiety was more pronounced in women (p = 0.001). Yohimbine also significantly increased craving, compared with placebo (p < 0.05), following the cue presentation, and this effect was greater in women than men (gender by treatment interaction; p = 0.006). Yohimbine also increased salivary cortisol (p < 0.001) and dehydroepiandrosterone (p = 0.003) levels, regardless of diagnostic group. Women had a significantly greater heart rate response following yohimbine as compared with men (p < 0.001). Stress may increase the salience of cocaine cues for cocaine-dependent women as compared with men. This suggests gender differences in vulnerability to craving and relapse under stressful conditions.
    Psychopharmacology 04/2014; · 4.06 Impact Factor
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    ABSTRACT: BACKGROUND: The ability to predict potential for relapse to substance use following treatment could be very useful in targeting aftercare strategies. Recently, a number of investigators have focused on using neural activity measured by fMRI to predict relapse propensity. The purpose of the present study was to use fMRI to investigate prospective associations between brain reactivity to cocaine and response inhibition cues and relapse to cocaine use. METHODS: Thirty cocaine-dependent participants with clean cocaine urine drug screens (UDS) completed a baseline fMRI scan, including a cocaine-cue reactivity task and a go no-go response inhibition task. After participating in a brief clinical trial of d-cycloserine for the facilitation of cocaine-cue extinction, they returned for a one-week follow-up UDS. Associations between baseline activation to cocaine and inhibition cues and relapse to cocaine use were explored. RESULTS: Positive cocaine UDS was significantly associated with cocaine-cue activation in the right putamen and insula, as well as bilateral occipital regions. Associations between positive cocaine UDS and activation to no-go cues were concentrated in the postcentral gyri, a region involved in response execution. CONCLUSIONS: Although preliminary, these results suggest that brain imaging may be a useful tool for predicting risk for relapse in cocaine-dependent individuals. Further, larger-scale naturalistic studies are needed to corroborate and extend these findings.
    Drug and alcohol dependence 05/2013; · 3.60 Impact Factor
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    ABSTRACT: Childhood trauma has been associated adult stress-related disorders. However, little is known about physiologic alterations in adults with a history of early life trauma that do not have current psychiatric or medical diagnoses. In this study, the relationships between childhood adversity and cytokine and C-reactive protein (CRP) levels in healthy adults were examined. Participants included men (n = 18) and women (n = 20) who did not meet DSM-IV criteria for Axis I psychiatric disorders or any major medical illness. Cytokine and CRP levels were obtained from baseline blood samples. Subjects completed the Early Trauma Inventory Self Report (ETI-SR). The primary outcomes included serum interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL1-β), and CRP levels. In addition, the mean numbers of traumatic experiences (sexual, physical, emotional, general, and the summed total) were measured. Significant positive associations were found between the total ETI score and IL-6 (p = 0.05), IL1-β (p < 0.05), and TNF-α (p = 0.01). Significant positive correlations were found between the number of general traumas and IL1-β (p < 0.05), TNF-α (p < 0.05), and IL-6 (p < 0.01). Neither the total number of traumas nor any of the trauma subscales were significantly associated with CRP levels. The positive association between childhood trauma and basal cytokine levels supports the extant literature demonstrating the long-term impact of childhood trauma and stress on homeostatic systems. Importantly, this association was found in healthy adults, suggesting that these alterations may precede the development of significant stress-related psychiatric disorder or disease.
    Journal of Psychiatric Research 05/2013; 47(5):604-10. · 4.09 Impact Factor
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    ABSTRACT: RATIONALE: Stress has been shown to be a significant factor in the maintenance of marijuana use. Oxytocin is a hypothalamic neuropeptide that has been shown to moderate behavioral responding to stress as well as play a role in the neuroadaptations that occur as a consequence of long-term drug use. OBJECTIVES: The current study evaluated the impact of oxytocin pretreatment on craving, stress, and anxiety responses following a psychosocial stress task in marijuana-dependent individuals. METHODS: In a laboratory setting, baseline measurements of craving (assessed using the Marijuana Craving Questionnaire; MCQ), salivary cortisol and dehydroepiandrosterone (DHEA), stress, and anxiety were collected in 16 participants (age 19-40) meeting DSM-IV criteria for marijuana dependence. Participants were then administered either oxytocin 40 IU (n = 8) or placebo (n = 8) nasal spray prior to completion of the Trier Social Stress Task (TSST). Measurements were repeated pre-TSST, immediately post-TSST, and 5-, 35-, and 60-min post-TSST. RESULTS: Oxytocin reduced both MCQ total score and DHEA levels from before to after the TSST. It also decreased anxiety, but not subjective stress ratings. CONCLUSIONS: Although preliminary, these results suggest that oxytocin may play a role in the amelioration of stress-induced reactivity and craving in marijuana-dependent individuals.
    Psychopharmacology 04/2013; · 4.06 Impact Factor
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    ABSTRACT: RATIONALE: D: -Cycloserine (DCS), a partial glutamate N-methyl-D: -aspartate (NMDA) receptor agonist, enhances extinction of conditioned fear responding; preliminary data suggest that it may facilitate extinction of drug cue reactivity. OBJECTIVE: This study investigates DCS effects on cocaine cue craving and drug use in cocaine-dependent subjects. METHODS: Thirty-two subjects were randomly assigned to receive (1) DCS only, (2) DCS before sessions 1 and 3, placebo (PBO) before session 2, or (3) PBO only 15-min before each of 3 1-h cocaine cue exposure sessions conducted 1 day apart. Craving ratings were obtained before, during, and after sessions. Drug use and cue-induced craving were assessed 1 week after the last cue session. RESULTS: Repeated presentation of cocaine cues resulted in decreased craving both within and between sessions. DCS did not facilitate extinction learning and may have enhanced craving. The group that received three doses of DCS had significantly higher craving than the PBO group at the baseline ratings taken before sessions 2 and 3, as well as significantly higher cue-induced craving at follow-up. The group that received two doses of DCS did not differ from the PBO group. There were no group differences in postextinction cocaine use. CONCLUSIONS: The reduction of cocaine cue reactivity in the PBO group suggests that the study procedures were sufficient to produce extinction. Under these conditions, DCS did not facilitate extinction and may have enhanced craving. Further studies of glutamatergic agents and extinction in cocaine dependence should include consideration of procedural variables that could have a major impact on study outcomes.
    Psychopharmacology 04/2013; 226(4):739-746. · 4.06 Impact Factor
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    ABSTRACT: RATIONALE/OBJECTIVES: This study examined the effects of propranolol vs. placebo, administered immediately after a "retrieval" session of cocaine cue exposure (CCE), on craving and physiological responses occurring 24 h later during a subsequent "test" session of CCE. It was hypothesized that compared to placebo-treated cocaine-dependent (CD) individuals, propranolol-treated CD individuals would evidence attenuated craving and physiological reactivity during the test session. Secondarily, it was expected that group differences identified in the test session would be evident at a 1-week follow-up CCE session. Exploratory analyses of treatment effects on cocaine use were also performed at follow-up. METHODS: CD participants received either 40 mg propranolol or placebo immediately following a "retrieval" CCE session. The next day, participants received a "test" session of CCE that was identical to the "retrieval" session except no medication was administered. Participants underwent a "follow-up" CCE session 1 week later. Craving and other reactivity measures were obtained at multiple time points during the CCE sessions. RESULTS: Propranolol- vs. placebo-treated participants evidenced significantly greater attenuation of craving and cardiovascular reactivity during the test session. Analysis of the follow-up CCE session data did not reveal any group differences. Although there was no evidence of treatment effects on cocaine use during follow-up, this study was insufficiently powered to rigorously evaluate differential cocaine use. CONCLUSIONS: This double-blind, placebo-controlled laboratory study provides the first evidence that propranolol administration following CCE may modulate memories for learning processes that subserve cocaine craving/cue reactivity in CD humans. Alternative interpretations of the findings were considered, and implications of the results for treatment were noted.
    Psychopharmacology 04/2013; 226(4):721. · 4.06 Impact Factor
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    ABSTRACT: BACKGROUND: The development of addiction is marked by a pathological associative learning process that imbues incentive salience to stimuli associated with drug use. Recent efforts to treat addiction have targeted this learning process using cue exposure therapy augmented with d-cycloserine (DCS), a glutamatergic agent hypothesized to enhance extinction learning. To better understand the impact of DCS-facilitated extinction on neural reactivity to drug cues, the present study reports fMRI findings from a randomized, double-blind, placebo-controlled trial of DCS-facilitated cue exposure for cocaine dependence. METHODS: Twenty-five participants completed two MRI sessions (before and after intervention), with a cocaine-cue reactivity fMRI task. The intervention consisted of 50mg of DCS or placebo, combined with two sessions of cocaine cue exposure and skills training. RESULTS: Participants demonstrated cocaine cue activation in a variety of brain regions at baseline. From the pre- to post-study scan, participants experienced decreased activation to cues in a number of regions (e.g., accumbens, caudate, frontal poles). Unexpectedly, placebo participants experienced decreases in activation to cues in the left angular and middle temporal gyri and the lateral occipital cortex, while DCS participants did not. CONCLUSIONS: Three trials of DCS-facilitated cue exposure therapy for cocaine dependence have found that DCS either increases or does not significantly impact response to cocaine cues. The present study adds to this literature by demonstrating that DCS may prevent extinction to cocaine cues in temporal and occipital brain regions. Although consistent with past research, results from the present study should be considered preliminary until replicated in larger samples.
    Drug and alcohol dependence 03/2013; · 3.60 Impact Factor
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    ABSTRACT: Background: Varenicline has been shown to reduce cigarette craving during a quit attempt. Objectives: Use BOLD fMRI to explore differences in smoking cue reactivity at baseline and after five weeks of varenicline smoking cessation treatment. Methods: Treatment-seeking nicotine-dependent adult smokers underwent BOLD fMRI scans with block presentation of visual smoking, neutral, and rest cues under two conditions: craving or resisting the urge to smoke at baseline and following 5 weeks of standard varenicline therapy. Data were analyzed using FMRI Expert Analysis Tool, version 5.98 of Functional Magnetic Imaging of the Brain Software Library focused on the smoking vs. neutral cue contrast at the individual and group level, Z>2.3 with cluster threshold p=0.05. Results: Twenty-one participants were scanned at baseline and 16 completed the study; 10 were abstinent at the 2(nd) session, confirmed with urinary cotinine. In the Crave Condition no significant differences were found between the abstinent and non-abstinent groups at either time point. During the baseline Resist Condition, the abstinent group compared to the non-abstinent group demonstrated activation in a distributed network involved in alertness, learning and memory. Additionally, within the abstinent group, increased activation of the superior frontal gyrus was found at baseline compared to week 5. Conclusion: Successful smoking cessation with varenicline is associated with increased activation, prior to a quit attempt, in brain areas related to attentiveness and memory while resisting the urge to smoke Scientific Significance: Varenicline may exert effects by both reducing craving and enhancing resistance to smoking urges during cue-elicited craving.
    The American Journal of Drug and Alcohol Abuse 03/2013; 39(2):92-8. · 1.55 Impact Factor
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    ABSTRACT: Preclinical findings suggest that the over-the-counter supplement N-acetylcysteine (NAC), via glutamate modulation in the nucleus accumbens, holds promise as a pharmacotherapy for substance dependence. The authors investigated NAC as a novel cannabis cessation treatment in adolescents, a vulnerable group for whom existing treatments have shown limited efficacy. In an 8-week double-blind randomized placebo-controlled trial, treatment-seeking cannabis-dependent adolescents (ages 15-21 years; N=116) received NAC (1200 mg) or placebo twice daily as well as a contingency management intervention and brief (<10 minutes) weekly cessation counseling. The primary efficacy measure was the odds of negative weekly urine cannabinoid test results during treatment among participants receiving NAC compared with those receiving placebo, in an intent-to-treat analysis. The primary tolerability measure was frequency of adverse events, compared by treatment group. Participants receiving NAC had more than twice the odds, compared with those receiving placebo, of having negative urine cannabinoid test results during treatment (odds ratio=2.4, 95% CI=1.1-5.2). Exploratory secondary abstinence outcomes favored NAC but were not statistically significant. NAC was well tolerated, with minimal adverse events. This is the first randomized controlled trial of pharmacotherapy for cannabis dependence in any age group to yield a positive primary cessation outcome in an intent-to-treat analysis. Findings support NAC as a pharmacotherapy to complement psychosocial treatment for cannabis dependence in adolescents.
    American Journal of Psychiatry 06/2012; 169(8):805-12. · 14.72 Impact Factor
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    ABSTRACT: Behavioral disinhibition has been suggested as both a cause and consequence of substance use disorders. Many studies examining associations between behavioral disinhibition and substance use history have focused on individuals with alcohol dependence or non-dependent college students. In the present study, the relationship between behavioral disinhibition and cocaine use history in individuals with cocaine dependence is examined. Forty-six non-treatment-seeking cocaine-dependent men and women completed impulsivity (Barratt impulsiveness scale; BIS) and novelty seeking (temperament and character inventory; TCI) questionnaires at the baseline visit of an ongoing study. Unadjusted, and adjusted for gender and age, Pearson correlations were calculated between BIS, TCI, and cocaine use variables from the structured clinical interview for DSM-IV and timeline follow-back (age of onset, quantity/frequency of past 30 day cocaine use). As expected, elevated motor impulsivity and novelty seeking were each associated with younger age of dependence onset. Also, individuals with lower levels of persistence on the TCI reported more days of cocaine use over the previous month. Unexpectedly, increased novelty seeking and attentional impulsivity were associated with fewer days of cocaine use and less money spent on cocaine, respectively. Controlling for age and gender did not substantially change the pattern of observed associations. The present study provides preliminary evidence for associations between behavioral disinhibition and cocaine use history in cocaine-dependent individuals. Given our relatively small sample size and the correlational nature of our findings, further research is needed to replicate and extend our results.
    Addictive behaviors 06/2012; 37(10):1185-8. · 2.25 Impact Factor
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    ABSTRACT: Identification of the motives for drug use is critical to the development of effective interventions. Furthermore, consideration of the differences in motives for drug use across substance dependent populations may assist in tailoring interventions. To date, few studies have systematically compared motives for substance use across drug classes. The current study examined motives for drug use between non-treatment seeking individuals with current prescription opioid, marijuana, or cocaine dependence. Participants (N=227) completed the Inventory of Drug-Taking Situations (IDTS; Annis, Turner & Sklar,1997), which contains eight subscales assessing motives for drug use. The findings revealed that prescription opioid dependent individuals scored significantly higher than all other groups on the Physical Discomfort, Testing Personal Control and Conflict with Others subscales. Both the prescription opioid and cocaine dependent groups scored significantly higher than the marijuana group on the Urges or a Temptation to Use subscale. In contrast, marijuana dependent individuals scored highest on the Pleasant Emotions and Pleasant Times with Others subscales. The marked differences revealed in motives for drug use could be used in the development and implementation of specific treatment interventions for prescription opioid, marijuana and cocaine dependent individuals.
    Addictive behaviors 04/2012; 37(4):373-8. · 2.25 Impact Factor
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    ABSTRACT: Motivation to change is believed to be a key factor in therapeutic success in substance use disorders; however, the neurobiological mechanisms through which motivation to change impacts decreased substance use remain unclear. Existing research is conflicting, with some investigations supporting decreased and others reporting increased frontal activation to drug cues in individuals seeking treatment for substance use disorders. The present study investigated the relationship between motivation to change cocaine use and cue-elicited brain activity in cocaine-dependent individuals using two conceptualizations of 'motivation to change': (1) current treatment status (i.e. currently receiving versus not receiving outpatient treatment for cocaine dependence) and (2) self-reported motivation to change substance use, using the Stages of Change Readiness and Treatment Eagerness Scale. Thirty-eight cocaine-dependent individuals (14 currently in treatment) completed a diagnostic assessment and an fMRI cocaine cue-reactivity task. Whole-brain analyses demonstrated that both treatment-seeking and motivated participants had lower activation to cocaine cues in a wide variety of brain regions in the frontal, occipital, temporal and cingulate cortices relative to non-treatment-seeking and less motivated participants. Future research is needed to explain the mechanism by which treatment and/or motivation impacts neural cue reactivity, as such work could potentially aid in the development of more effective therapeutic techniques for substance-dependent patients.
    Addiction Biology 03/2012; · 5.91 Impact Factor
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    ABSTRACT: Drug craving is an important motivational phenomenon among addicted individuals, and successful management of craving is essential to both the initiation and maintenance of abstinence. Although craving in response to drug cues is common in drug-dependent individuals, it is not universal. At the present time, it is not known why approximately 20-30% of all addicted persons fail to report appreciable craving in laboratory-based cue reactivity studies. This study examined the possibility that alexithymia, a personality attribute characterized by a difficulty identifying and describing emotions, may contribute to the impoverished cue-elicited craving experienced by some addicts. Specifically, we tested the hypothesis that alexithymia, as measured by the Toronto Alexithymia Scale (TAS), would be inversely related to the magnitude of cue-elicited craving obtained in a cue reactivity protocol. Forty methamphetamine-dependent individuals completed the TAS and provided craving ratings for methamphetamine after presentation of methamphetamine-associated cues. Thirteen participants (32%) reported no methamphetamine cue-elicited craving. Contrary to expectation, TAS factor 1 (a measure of difficulty identifying feelings) scores were positively associated with cue-elicited craving. Thus, the results suggest that increasing difficulty-identifying feelings may be associated with higher cue-elicited craving. Clinical implications for this finding are discussed.
    American Journal on Addictions 03/2012; 21(2):130-5. · 1.74 Impact Factor
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    ABSTRACT: Adolescent substance abuse remains a public health problem, and more effective treatment approaches are needed. The study aims to determine the feasibility and preliminary effectiveness of implementing a cost-effective contingency management (CM) intervention in community substance abuse treatment for adolescents with marijuana use disorders. Thirty-one adolescents with primary marijuana use disorder enrolled in a community treatment were randomized into either a prize-based CM intervention contingent when submitting negative urine drug screens (UDS) or a noncontingent control group. There were no significant group differences in percent negative UDS, sustained negative UDS, or retention in treatment. CM was difficult to integrate into community treatment programs and did not seem to be an effective adjunct to standard community substance abuse treatment for adolescents with marijuana use disorders. Modifying the CM procedure for adolescents, changing staff attitudes toward CM, and/or combining CM with other evidence-based psychosocial treatment may improve outcomes.
    Journal of Child and Adolescent Psychiatric Nursing 02/2012; 25(1):33-41.
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    ABSTRACT: Chronic methamphetamine abuse is associated with cognitive deficits that may impede treatment in methamphetamine-dependent patients. Exposure to methamphetamine-related cues can elicit intense craving in chronic users of the drug, but the effects of exposure to drug cues on cognitive performance in these individuals are unknown. This study assessed whether exposure to methamphetamine-related visual cues can elicit craving and/or alter dual task cognitive performance in 30 methamphetamine-dependent subjects and 30 control subjects in the laboratory. Reaction time, response errors, and inhibition errors were assessed on an auditory Go-No Go task performed by adult participants (total N = 60) while watching neutral versus methamphetamine-related video cues. Craving was assessed with the Within-Session Rating Scale modified for methamphetamine-dependent subjects. Exposure to methamphetamine-related cues elicited craving only in methamphetamine-dependent subjects. Even in the absence of methamphetamine cues, methamphetamine-dependent subjects exhibited slower reaction times and higher rates of both inhibition and response errors than control subjects did. Upon exposure to methamphetamine cues, rates of both response errors and inhibition errors increased significantly in methamphetamine-dependent subjects. Control subjects exhibited no increase in inhibition errors and only slightly increased rates of response errors upon exposure to methamphetamine cues. Response error rates, but not inhibition error rates or reaction times, during methamphetamine cue exposure were significantly associated with craving scores in methamphetamine-dependent subjects. Methamphetamine-dependent individuals exhibit cognitive performance deficits that are more pronounced during exposure to methamphetamine-related cues. Interventions that reduce cue reactivity may have utility in the treatment of methamphetamine dependence.
    The American Journal of Drug and Alcohol Abuse 01/2012; 38(3):251-9. · 1.55 Impact Factor
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    ABSTRACT: This 8-week, open-label trial assessed the efficacy of methylphenidate transdermal system (MTS) in 14 adult individuals diagnosed with ADHD and with a history of stimulant misuse, abuse, or dependence. The primary efficacy endpoint was the Wender-Reimherr Adult ADHD Scale (WRAADS), and secondary efficacy endpoints included the Clinical Global Impression (CGI) ratings and substance abuse as quantified by urine drug screens and self-reported use. Significant improvements from baseline were found on both the WRAADS and CGI measurements. No abuse of the study medication was observed. The findings suggested that MTS may improve ADHD symptoms in adults with a history of stimulant misuse; however, there were limitations. The study data showed the need for subsequent randomized studies that further explore findings made in this study.
    Journal of Attention Disorders 10/2011; 15(7):539-44. · 2.16 Impact Factor
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    ABSTRACT: Inconsistencies in reports on methamphetamine (METH) associated cognitive dysfunction may be attributed, at least in part, to the diversity of study sample features (eg, clinical and demographic characteristics). The current study assessed cognitive function in a METH-dependent population from rural South Carolina, and the impact of demographic and clinical characteristics on performance. Seventy-one male (28.2%) and female (71.8%) METH-dependent subjects were administered a battery of neurocognitive tests including the Test of Memory Malingering (TOMM), Shipley Institute of Living Scale, Paced Auditory Serial Addition Test (PASAT), Symbol Digit Modalities Test (SDMT), Grooved Pegboard Test, California Verbal Learning Test (CVLT), and Wisconsin Card Sorting Test (WCST). Demographic and clinical characteristics (eg, gender, frequency of METH use) were examined as predictors of performance. Subjects scored significantly lower than expected on one test of attention and one of fine motor function, but performed adequately on all other tests. There were no predictors of performance on attention; however, more frequent METH use was associated with better performance for males and worse for females on fine motor skills. The METH-dependent individuals in this population exhibit very limited cognitive impairment. The marked differences in education, Intellectual Quotient (IQ), and gender in our sample when compared to the published literature may contribute to these findings. Characterization of the impact of clinical and/or demographic features on cognitive deficits could be important in guiding the development of treatment interventions.
    American Journal on Addictions 09/2011; 20(5):447-55. · 1.74 Impact Factor