Publications by authors named "Hamed Ekhtiari"

75 Publications

Sex differences in circulating inflammatory mediators as a function of substance use disorder.

Drug Alcohol Depend 2021 Feb 15;221:108610. Epub 2021 Feb 15.

Laureate Institute for Brain Research, Tulsa, OK, USA; Oxley College of Health Sciences, The University of Tulsa, Tulsa, OK, USA.

Background: Substance use disorders (SUD) with comorbid depression and anxiety are linked to poor treatment outcome and relapse. Although some depressed individuals exhibit elevated blood-based inflammation (interleukin-6 [IL-6] and C reactive protein [CRP]), few studies have examined whether the presence of SUD exacerbates inflammation.

Methods: Treatment-seeking individuals with major depressive disorder (MDD), anxiety disorders, and/or SUD (N = 160; 80 % with MDD) recruited into the Tulsa 1000 study provided blood samples, participated in clinical interviews, and completed a questionnaire battery querying symptoms of current psychopathology and emotional processing. Analyses followed a multistep process. First, groups were created on the presence versus absence of 1+ lifetime SUD diagnoses: SUD+ (37 F, 43 M) and SUD- (60 F, 20 M). Second, a principal component analysis (PCA) of questionnaire data resulted in two factors, one indexing negative emotionality/withdrawal motivation and one measuring positive emotionality/approach motivation. Third, SUD groups, extracted PCA factors, and nuisance covariates (age, body mass index [BMI], nicotine use, psychotropic medication [and hormone/contraception use in females]) were entered as simultaneous predictors of blood-based inflammation (IL-6, IL-8, IL-10, tumor necrosis factor-α, and CRP).

Results: Within females, SUD + exhibited higher IL-8 and IL-10 but lower CRP levels than SUD-. In contrast, SUD was not associated with biomarker levels in males. Across sexes, higher BMI was linked to higher IL-6 and CRP levels, and within the five biomarkers, IL-6 and CRP shared the most variance.

Conclusion: These findings point to sex-specific inflammatory profiles as a function of SUD that may provide new targets for intervention.
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http://dx.doi.org/10.1016/j.drugalcdep.2021.108610DOI Listing
February 2021

Group and individual level variations between symmetric and asymmetric DLPFC montages for tDCS over large scale brain network nodes.

Sci Rep 2021 Jan 14;11(1):1271. Epub 2021 Jan 14.

Laureate Institute for Brain Research (LIBR), Tulsa, OK, USA.

Two challenges to optimizing transcranial direct current stimulation (tDCS) are selecting between, often similar, electrode montages and accounting for inter-individual differences in response. These two factors are related by how tDCS montage determines current flow through the brain considered across or within individuals. MRI-based computational head models (CHMs) predict how brain anatomy determines electric field (EF) patterns for a given tDCS montage. Because conventional tDCS produces diffuse brain current flow, stimulation outcomes may be understood as modulation of global networks. Therefore, we developed a network-led, rather than region-led, approach. We specifically considered two common "frontal" tDCS montages that nominally target the dorsolateral prefrontal cortex; asymmetric "unilateral" (anode/cathode: F4/Fp1) and symmetric "bilateral" (F4/F3) electrode montages. CHMs of 66 participants were constructed. We showed that cathode location significantly affects EFs in the limbic network. Furthermore, using a finer parcellation of large-scale networks, we found significant differences in some of the main nodes within a network, even if there is no difference at the network level. This study generally demonstrates a methodology for considering the components of large-scale networks in CHMs instead of targeting a single region and specifically provides insight into how symmetric vs asymmetric frontal tDCS may differentially modulate networks across a population.
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http://dx.doi.org/10.1038/s41598-020-80279-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7809198PMC
January 2021

Editorial: Brain and Cognition for Addiction Medicine: From Prevention to Recovery.

Front Psychiatry 2020 26;11:590030. Epub 2020 Nov 26.

Laureate Institute for Brain Research, Tulsa, OK, United States.

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http://dx.doi.org/10.3389/fpsyt.2020.590030DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7732613PMC
November 2020

Chronic heroin use disorder and the brain: Current evidence and future implications.

Prog Neuropsychopharmacol Biol Psychiatry 2020 Oct 23:110148. Epub 2020 Oct 23.

Division of Population and Behavioural Sciences, University of St Andrews, Fife, Scotland, United Kingdom.

The incidence of chronic heroin use disorder, including overdose deaths, has reached epidemic proportions. Here we summarise and evaluate our knowledge of the relationship between chronic heroin use disorder and the brain through a narrative review. A broad range of areas was considered including causal mechanisms, cognitive and neurological consequences of chronic heroin use and novel neuroscience-based clinical interventions. Chronic heroin use is associated with limited or very limited evidence of impairments in memory, cognitive impulsivity, non-planning impulsivity, compulsivity and decision-making. Additionally, there is some evidence for certain neurological disorders being caused by chronic heroin use, including toxic leukoencephalopathy and neurodegeneration. However, there is insufficient evidence on whether these impairments and disorders recover after abstinence. Whilst there is a high prevalence of comorbid psychiatric disorders, there is no clear evidence that chronic heroin use per se causes depression, bipolar disorder, PTSD and/or psychosis. Despite the growing burden on society from heroin use, knowledge of the long-term effects of chronic heroin use disorder on the brain remains limited. Nevertheless, there is evidence for progress in neuroscience-based interventions being made in two areas: assessment (cognitive assessment and neuroimaging) and interventions (cognitive training/remediation and neuromodulation). Longitudinal studies are needed to unravel addiction and neurotoxic mechanisms and clarify the role of pre-existing psychiatric symptoms and cognitive impairments.
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http://dx.doi.org/10.1016/j.pnpbp.2020.110148DOI Listing
October 2020

fMRI and transcranial electrical stimulation (tES): A systematic review of parameter space and outcomes.

Prog Neuropsychopharmacol Biol Psychiatry 2021 Apr 21;107:110149. Epub 2020 Oct 21.

Laureate Institute for Brain Research, Tulsa, OK, USA. Electronic address:

The combination of non-invasive brain stimulation interventions with human brain mapping methods have supported research beyond correlational associations between brain activity and behavior. Functional MRI (fMRI) partnered with transcranial electrical stimulation (tES) methods, i.e., transcranial direct current (tDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation, explore the neuromodulatory effects of tES in the targeted brain regions and their interconnected networks and provide opportunities for individualized interventions. Advances in the field of tES-fMRI can be hampered by the methodological variability between studies that confounds comparability/replicability. In order to explore variability in the tES-fMRI methodological parameter space (MPS), we conducted a systematic review of 222 tES-fMRI experiments (181 tDCS, 39 tACS and 2 tRNS) published before February 1, 2019, and suggested a framework to systematically report main elements of MPS across studies. Publications dedicated to tRNS-fMRI were not considered in this systematic review. We have organized main findings in terms of fMRI modulation by tES. tES modulates activation and connectivity beyond the stimulated areas particularly with prefrontal stimulation. There were no two studies with the same MPS to replicate findings. We discuss how to harmonize the MPS to promote replication in future studies.
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http://dx.doi.org/10.1016/j.pnpbp.2020.110149DOI Listing
April 2021

COVID-19 and Substance Use Disorder: Study Protocol for the International Society of Addiction Medicine Practice and Policy Interest Group Global Survey.

Basic Clin Neurosci 2020 Mar-Apr;11(2):155-162. Epub 2020 Apr 15.

Department of Psychiatry, Tehran University of Medical Sciences, Tehran, Iran; Substance Abuse and Dependence Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.

Introduction: As one of the major health problems in the present century, the COVID-19 pandemic affected all parts of the global communities and the health of substance users are potentially at a greater risk of harm. This global study has been designed and conducted by the International Society of Addiction Medicine Practice and Policy Interest Group (ISAM-PPIG) to understand better the health related issues of people with Substance Use Disorders (SUD) as well as responses of the relevant health care systems during the pandemic.

Methods: This is a cross-sectional study using convenient sampling. The data gathering was carried out with two follow-up stages each two months apart through an online conducted survey prepared using Google platform. The survey started by emergence of COVID-19 as a pandemic in March 2020 and respondents were followed till September 2020 when most of the initial lockdowns by most countries are supposed to be reopened.

Ethics And Dissemination: The study was approved by the ethics committee of University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. The results will be published in relevant peer reviewing journals and communicated with different international stakeholders.
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http://dx.doi.org/10.32598/bcn.11.covid19.2545.1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7368101PMC
April 2020

COVID-19 and Substance Use Disorders: Recommendations to a Comprehensive Healthcare Response. An International Society of Addiction Medicine Practice and Policy Interest Group Position Paper.

Basic Clin Neurosci 2020 Mar-Apr;11(2):133-150. Epub 2020 Apr 12.

Department of Psychiatry, Tehran University of Medical Sciences, Tehran, Iran.

Coronavirus Disease 2019 (COVID-19) is escalating all over the world and has higher morbidities and mortalities in certain vulnerable populations. People Who Use Drugs (PWUD) are a marginalized and stigmatized group with weaker immunity responses, vulnerability to stress, poor health conditions, high-risk behaviors, and lower access to health care services. These conditions put them at a higher risk of COVID-19 infection and its complications. In this paper, an international group of experts on addiction medicine, infectious diseases, and disaster psychiatry explore the possible raised concerns in this issue and provide recommendations to manage the comorbidity of COVID-19 and Substance Use Disorder (SUD).
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http://dx.doi.org/10.32598/bcn.11.covid19.1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7368103PMC
April 2020

Evaluating the resource allocation index as a potential fMRI-based biomarker for substance use disorder.

Drug Alcohol Depend 2020 11 9;216:108211. Epub 2020 Aug 9.

Laureate Institute for Brain Research, 6655 South Yale Ave., Tulsa, OK, 74136, United States; Department of Community Medicine, Oxley Health Sciences, The University of Tulsa, 1215 S. Boulder Ave, Tulsa, OK, 74119, United States; Department of Psychiatry, University of California, San Diego, United States. Electronic address:

Background: There is a lack of neuroscience-based biomarkers for the diagnosis, treatment and monitoring of individuals with substance use disorders (SUD). The resource allocation index (RAI), a measure of the interrelationship between salience, executive control and default-mode brain networks (SN, ECN, and DMN), has been proposed as one such biomarker. However, the RAI has yet to be extensively tested in SUD samples.

Methods: The present analysis compared RAI scores between individuals with stimulant and/or opioid use disorders (SUD; n = 139, abstinent 4-365 days) and healthy controls (HC; n = 56) who had completed resting-state functional magnetic resonance imaging (fMRI) scans within the context of the Tulsa 1000 cohort. First, we used independent component analysis (ICA) to identify the SN, ECN, and DMN and extract their time series data. Second, we used multiple permutations of automatically identified networks to compute RAI as reported in the fMRI literature.

Results: First, the RAI as a metric depended substantially on the approach that was used to define the network components. Second, regardless of the selection of networks, after controlling for multiple testing there was no difference in RAI scores between SUD and HC. Third, the RAI was not associated with any substance use-related self-report measures.

Conclusion: Taken together, these findings do not provide evidence that RAI can be used as an fMRI-derived biomarker for the severity or diagnosis of individuals with SUD.
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http://dx.doi.org/10.1016/j.drugalcdep.2020.108211DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7609625PMC
November 2020

Imprecise action selection in substance use disorder: Evidence for active learning impairments when solving the explore-exploit dilemma.

Drug Alcohol Depend 2020 10 6;215:108208. Epub 2020 Aug 6.

Laureate Institute for Brain Research, Tulsa, OK, USA.

Background: Substance use disorders (SUDs) are a major public health risk. However, mechanisms accounting for continued patterns of poor choices in the face of negative life consequences remain poorly understood.

Methods: We use a computational (active inference) modeling approach, combined with multiple regression and hierarchical Bayesian group analyses, to examine how treatment-seeking individuals with one or more SUDs (alcohol, cannabis, sedatives, stimulants, hallucinogens, and/or opioids; N = 147) and healthy controls (HCs; N = 54) make choices to resolve uncertainty within a gambling task. A subset of SUDs (N = 49) and HCs (N = 51) propensity-matched on age, sex, and verbal IQ were also compared to replicate larger group findings.

Results: Results indicate that: (a) SUDs show poorer task performance than HCs (p = 0.03, Cohen's d = 0.33), with model estimates revealing less precise action selection mechanisms (p = 0.004, d = 0.43), a lower learning rate from losses (p = 0.02, d = 0.36), and a greater learning rate from gains (p = 0.04, d = 0.31); and (b) groups do not differ significantly in goal-directed information seeking.

Conclusions: Findings suggest a pattern of inconsistent behavior in response to positive outcomes in SUDs combined with a tendency to attribute negative outcomes to chance. Specifically, individuals with SUDs fail to settle on a behavior strategy despite sufficient evidence of its success. These learning impairments could help account for difficulties in adjusting behavior and maintaining optimal decision-making during and after treatment.
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http://dx.doi.org/10.1016/j.drugalcdep.2020.108208DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7502502PMC
October 2020

Guidelines for TMS/tES clinical services and research through the COVID-19 pandemic.

Brain Stimul 2020 Jul - Aug;13(4):1124-1149. Epub 2020 May 12.

Laureate Institute for Brain Research, Tulsa, OK, USA. Electronic address:

Background: The COVID-19 pandemic has broadly disrupted biomedical treatment and research including non-invasive brain stimulation (NIBS). Moreover, the rapid onset of societal disruption and evolving regulatory restrictions may not have allowed for systematic planning of how clinical and research work may continue throughout the pandemic or be restarted as restrictions are abated. The urgency to provide and develop NIBS as an intervention for diverse neurological and mental health indications, and as a catalyst of fundamental brain research, is not dampened by the parallel efforts to address the most life-threatening aspects of COVID-19; rather in many cases the need for NIBS is heightened including the potential to mitigate mental health consequences related to COVID-19.

Objective: To facilitate the re-establishment of access to NIBS clinical services and research operations during the current COVID-19 pandemic and possible future outbreaks, we develop and discuss a framework for balancing the importance of NIBS operations with safety considerations, while addressing the needs of all stakeholders. We focus on Transcranial Magnetic Stimulation (TMS) and low intensity transcranial Electrical Stimulation (tES) - including transcranial Direct Current Stimulation (tDCS) and transcranial Alternating Current Stimulation (tACS).

Methods: The present consensus paper provides guidelines and good practices for managing and reopening NIBS clinics and laboratories through the immediate and ongoing stages of COVID-19. The document reflects the analysis of experts with domain-relevant expertise spanning NIBS technology, clinical services, and basic and clinical research - with an international perspective. We outline regulatory aspects, human resources, NIBS optimization, as well as accommodations for specific demographics.

Results: A model based on three phases (early COVID-19 impact, current practices, and future preparation) with an 11-step checklist (spanning removing or streamlining in-person protocols, incorporating telemedicine, and addressing COVID-19-associated adverse events) is proposed. Recommendations on implementing social distancing and sterilization of NIBS related equipment, specific considerations of COVID-19 positive populations including mental health comorbidities, as well as considerations regarding regulatory and human resource in the era of COVID-19 are outlined. We discuss COVID-19 considerations specifically for clinical (sub-)populations including pediatric, stroke, addiction, and the elderly. Numerous case-examples across the world are described.

Conclusion: There is an evident, and in cases urgent, need to maintain NIBS operations through the COVID-19 pandemic, including anticipating future pandemic waves and addressing effects of COVID-19 on brain and mind. The proposed robust and structured strategy aims to address the current and anticipated future challenges while maintaining scientific rigor and managing risk.
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http://dx.doi.org/10.1016/j.brs.2020.05.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7217075PMC
July 2020

Image-Derived Phenotyping Informed by Independent Component Analysis-An Atlas-Based Approach.

Front Neurosci 2020 21;14:118. Epub 2020 Feb 21.

Laureate Institute for Brain Research, Tulsa, OK, United States.

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http://dx.doi.org/10.3389/fnins.2020.00118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7047320PMC
February 2020

Methamphetamine and Opioid Cue Database (MOCD): Development and Validation.

Drug Alcohol Depend 2020 04 26;209:107941. Epub 2020 Feb 26.

Laureate Institute of Brain Research, 6655 South Yale Ave, Tulsa, OK, 74136, United States.

Introduction: Drug cue reactivity (DCR) is widely used in experimental settings for both assessment and intervention. There is no validated database of pictorial cues available for methamphetamine and opioids.

Methods: 360 images in three-groups (methamphetamine, opioid and neutral (control)) matched for their content (objects, hands, faces and actions) were selected in an initial development phase. 28 participants with a history of both methamphetamine and opioid use (37.71 ± 8.11 years old, 12 female) with over six months of abstinence were asked to rate images for craving, valence, arousal, typicality and relatedness.

Results: All drug images were differentiated from neutral images. Drug related images received higher arousal and lower valence ratings compared to neutral images (craving (0-100) for neutral (11.5 ± 21.9), opioid (87.7 ± 18.5) and methamphetamine (88 ± 18), arousal (1-9) for neutral (2.4 ± 1.9), opioid (4.6 ± 2.7) and methamphetamine (4.6 ± 2.6), and valence (1-9) for neutral (4.8 ± 1.3), opioid (4.4 ± 1.9) and methamphetamine (4.4 ± 1.8)). There is no difference between methamphetamine and opioid images in craving, arousal and valence. There is a significant positive relationship between the amount of time that participants spent on drug-related images and the craving they reported for the image. Every 10 points of craving were associated with an increased response time of 383 ms. Three image sets were automatically selected for equivalent fMRI tasks (methamphetamine and opioids) from the database (tasks are available at github).

Conclusion: The methamphetamine and opioid cue database (MOCD) provides a resource of validated images/tasks for future DCR studies. Additionally, researchers can select several sets of unique but equivalent images based-on their psychological/physical characteristics for multiple assessments/interventions.
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http://dx.doi.org/10.1016/j.drugalcdep.2020.107941DOI Listing
April 2020

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

Front Psychiatry 2019 23;10:877. Epub 2019 Dec 23.

Laureate Institute for Brain Research, University of Tulsa, Tulsa, OK, United States.

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.
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http://dx.doi.org/10.3389/fpsyt.2019.00877DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6935942PMC
December 2019

Methodology for tDCS integration with fMRI.

Hum Brain Mapp 2020 05 24;41(7):1950-1967. Epub 2019 Dec 24.

Laureate Institute for Brain Research, Tulsa, Oklahoma.

Understanding and reducing variability of response to transcranial direct current stimulation (tDCS) requires measuring what factors predetermine sensitivity to tDCS and tracking individual response to tDCS. Human trials, animal models, and computational models suggest structural traits and functional states of neural systems are the major sources of this variance. There are 118 published tDCS studies (up to October 1, 2018) that used fMRI as a proxy measure of neural activation to answer mechanistic, predictive, and localization questions about how brain activity is modulated by tDCS. FMRI can potentially contribute as: a measure of cognitive state-level variance in baseline brain activation before tDCS; inform the design of stimulation montages that aim to target functional networks during specific tasks; and act as an outcome measure of functional response to tDCS. In this systematic review, we explore methodological parameter space of tDCS integration with fMRI spanning: (a) fMRI timing relative to tDCS (pre, post, concurrent); (b) study design (parallel, crossover); (c) control condition (sham, active control); (d) number of tDCS sessions; (e) number of follow up scans; (f) stimulation dose and combination with task; (g) functional imaging sequence (BOLD, ASL, resting); and (h) additional behavioral (cognitive, clinical) or quantitative (neurophysiological, biomarker) measurements. Existing tDCS-fMRI literature shows little replication across these permutations; few studies used comparable study designs. Here, we use a representative sample study with both task and resting state fMRI before and after tDCS in a crossover design to discuss methodological confounds. We further outline how computational models of current flow should be combined with imaging data to understand sources of variability. Through the representative sample study, we demonstrate how modeling and imaging methodology can be integrated for individualized analysis. Finally, we discuss the importance of conducting tDCS-fMRI with stimulation equipment certified as safe to use inside the MR scanner, and of correcting for image artifacts caused by tDCS. tDCS-fMRI can address important questions on the functional mechanisms of tDCS action (e.g., target engagement) and has the potential to support enhancement of behavioral interventions, provided studies are designed rationally.
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http://dx.doi.org/10.1002/hbm.24908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7267907PMC
May 2020

Disrupted resting-state brain functional network in methamphetamine abusers: A brain source space study by EEG.

PLoS One 2019 11;14(12):e0226249. Epub 2019 Dec 11.

Department of Biomedical Engineering, University of Connecticut, Storrs, CT, United States of America.

This study aimed to examine the effects of chronic methamphetamine use on the topological organization of whole-brain functional connectivity network (FCN) by reconstruction of neural-activity time series at resting-state. The EEG of 36 individuals with methamphetamine use disorder (IWMUD) and 24 normal controls (NCs) were recorded, pre-processed and source-reconstructed using standardized low-resolution tomography (sLORETA). The brain FCNs of participants were constructed and between-group differences in network topological properties were investigated using graph theoretical analysis. IWMUD showed decreased characteristic path length, increased clustering coefficient and small-world index at delta and gamma frequency bands compared to NCs. Moreover, abnormal changes in inter-regional connectivity and network hubs were observed in all the frequency bands. The results suggest that the IWMUD and NCs have distinct FCNs at all the frequency bands, particularly at the delta and gamma bands, in which deviated small-world brain topology was found in IWMUD.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0226249PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6906079PMC
March 2020

Computer-aided classifying and characterizing of methamphetamine use disorder using resting-state EEG.

Cogn Neurodyn 2019 Dec 7;13(6):519-530. Epub 2019 Aug 7.

5Iranian Center of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences (TUMS), Tehran, Iran.

Methamphetamine (meth) is potently addictive and is closely linked to high crime rates in the world. Since meth withdrawal is very painful and difficult, most abusers relapse to abuse in traditional treatments. Therefore, developing accurate data-driven methods based on brain functional connectivity could be helpful in classifying and characterizing the neural features of meth dependence to optimize the treatments. Accordingly, in this study, computation of functional connectivity using resting-state EEG was used to classify meth dependence. Firstly, brain functional connectivity networks (FCNs) of 36 meth dependent individuals and 24 normal controls were constructed by weighted phase lag index, in six frequency bands: delta (1-4 Hz), theta (4-8 Hz), alpha (8-15 Hz), beta (15-30 Hz), gamma (30-45 Hz) and wideband (1-45 Hz).Then, significant differences in graph metrics and connectivity values of the FCNs were used to distinguish the two groups. Support vector machine classifier had the best performance with 93% accuracy, 100% sensitivity, 83% specificity and 0.94 F-score for differentiating between MDIs and NCs. The best performance yielded when selected features were the combination of connectivity values and graph metrics in the beta frequency band.
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http://dx.doi.org/10.1007/s11571-019-09550-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6825232PMC
December 2019

The evolution of addiction treatment and harm reduction programs in Iran: a chaotic response or a synergistic diversity?

Addiction 2020 07 29;115(7):1395-1403. Epub 2019 Dec 29.

Integrated Substance Abuse Programs, University of California at Los Angeles, Los Angeles, CA, USA.

Backgrounds And Aims: Iran has 2.1 and 1.8% of its 15-64-year-old population living with illicit substance and opioid use disorders, respectively. To address these problems, Iran has been developing a large and multi-modality addiction treatment system, spanning the time before and after the Islamic Revolution.

Methods: Iran's current drug treatment scene is a combination of services, ranging from medical/harm reduction services to punitive/criminal justice programs. Included in this array of services are drop-in centers providing low-threshold harm reduction services, such as distribution of sterile needles and syringes; opioid maintenance treatment clinics providing methadone, buprenorphine and opium tincture; and abstinence-based residential centers. We will review the evolution of this system in four phases.

Results: In 1980, Iran's revolutionary government shut down all voluntary treatment programs and replaced them with residential correctional programs. The first shift in the addiction treatment policies came 15 years later after facing the negative consequences. Addiction is viewed as a disease, and new voluntary treatment centers offering non-agonist medications and psychosocial services were established. With an increased number of people who inject drugs and HIV/AIDS epidemics, in the second shift an extensive move towards harm reduction strategies and opioid-maintenance programs has been implemented to reduce HIV-related high-risk behavior. The emergence of a methamphetamine use crisis creating an increased number of socially marginalized addicted people resulted in public and political demands for stricter policies and ended in the third shift starting in 2010, with extended compulsory court-based residential programs. Currently, there is a new shift towards reducing the severity of criminal penalties for drug use/sales and promoting proposals for opium legalization.

Conclusion: Iran's evolutionary experience in developing a large addiction treatment program in a complex combination of medical/harm reduction and punitive/criminal justice addiction treatment can be examined in its political, clinical and pragmatic context.
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http://dx.doi.org/10.1111/add.14905DOI Listing
July 2020

Bias Toward Drug-Related Stimuli Is Affected by Loading Working Memory in Abstinent Ex-Methamphetamine Users.

Front Psychiatry 2019 22;10:776. Epub 2019 Oct 22.

Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.

There is a trade-off between drug-related impulsive process and cognitive reflective process among ex-drug abusers. The present study aimed to investigate the impulsive effects of methamphetamine-related stimuli on working memory (WM) performance by manipulating WM load in abstinent ex-methamphetamine users. Thirty abstinent ex-methamphetamine users and 30 nonaddict matched control participants were recruited in this study. We used a modified Sternberg task in which participants were instructed to memorize three different sets of methamphetamine-related and non-drug-related words (three, five, or seven words) while performing a secondary attention-demanding task as an interference. Repeated-measures ANOVA revealed that reaction times of abstinent ex-methamphetamine users increased during low WM load (three words) compared to the control group ( = 0.01). No significant differences were observed during high WM loads (five or seven words) (both 's > 0.1). Besides, reaction times of the experimental group during trials with high interference (three, five, or seven words) were not significantly different compared to the control group ( > 0.2). These findings imply that increasing WM load may provide an efficient buffer against attentional capture by salient stimuli (i.e., methamphetamine-related words). This buffer might modify the effect of interference bias. Besides, presenting methamphetamine-related stimuli might facilitate the encoding phase due to bias toward task-relevant stimuli. This finding has an important implication, suggesting that performing concurrent demanding tasks may reduce the power of salient stimuli and thus improve the efficiency of emotional regulation strategies.
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http://dx.doi.org/10.3389/fpsyt.2019.00776DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6817911PMC
October 2019

Efficacy of Neurocognitive Rehabilitation After Coronary Artery Bypass Graft Surgery in Improving Quality of Life: An Interventional Trial.

Front Psychol 2019 8;10:1759. Epub 2019 Aug 8.

Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran.

Introduction: Cognitive deficits are frequent after coronary artery bypass graft (CABG) surgery and consequently could lead to a decrease in quality of life. This is the first study that has been conducted with the aim of examining the efficacy of a computerized cognitive rehabilitation therapy (CCRT) in improving quality of life in patients after CABG surgery.

Methods: In this study, an interventional trial with pre-, post-, and follow-up assessments in active (CCRT), active control and control groups was conducted. Seventy-five patients after CABG surgery were selected and assigned to the groups ( = 25 for each group). CCRT consists of four modules of attention, working memory, response inhibition and processing speed training with graded schedule in 20-min sessions three times per week within 8 weeks. Cognitive functions (attention and working memory) were assessed by the tests of continuous performance, Flanker, useful field of view and digit span at three time points: pre- and post-intervention (T0 and T1) and 6-month follow-up (T2). Quality of life was assessed by the SF-36 questionnaire at the same time points. The CCRT group received the cognitive rehabilitation for 2 months, active control group received a sham version of CCRT in an equal time duration and control group did not receive any cognitive intervention.

Results: Repeated measures analysis of variance (ANOVA) revealed a time by group interaction on cognitive functions, with CCRT producing a significant improvement at T1 ( < 0.01) and these improvements were maintained at T2. Moreover, in CCRT and active control groups, quality of life (QoL) improved at T1 and these improvements remained stable throughout follow-up (T2). However, improvement of QoL in CCRT group was greater than improvement of QoL in the other two groups at T1. Pearson's correlation analysis shows a positive correlation between QoL improvement and sustained attention and working memory enhancement ( < 0.05).

Conclusion: Cognitive rehabilitation can lead to a significant improvement in the cognitive functions that have been trained in patients receiving CABG. Interestingly enough, cognitive rehabilitation can also improve quality of life in patients after CABG surgery and this improvement is maintained for at least 6 months.
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http://dx.doi.org/10.3389/fpsyg.2019.01759DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6694840PMC
August 2019

Transcranial electrical stimulation nomenclature.

Brain Stimul 2019 Nov - Dec;12(6):1349-1366. Epub 2019 Jul 17.

Department of Psychiatry & Behavioral Sciences, Department of Biomedical Engineering, Department of Electrical & Computer Engineering, Department of Neurosurgery, Duke University, Durham, NC, USA.

Transcranial electrical stimulation (tES) aims to alter brain function non-invasively by applying current to electrodes on the scalp. Decades of research and technological advancement are associated with a growing diversity of tES methods and the associated nomenclature for describing these methods. Whether intended to produce a specific response so the brain can be studied or lead to a more enduring change in behavior (e.g. for treatment), the motivations for using tES have themselves influenced the evolution of nomenclature, leading to some scientific, clinical, and public confusion. This ambiguity arises from (i) the infinite parameter space available in designing tES methods of application and (ii) varied naming conventions based upon the intended effects and/or methods of application. Here, we compile a cohesive nomenclature for contemporary tES technologies that respects existing and historical norms, while incorporating insight and classifications based on state-of-the-art findings. We consolidate and clarify existing terminology conventions, but do not aim to create new nomenclature. The presented nomenclature aims to balance adopting broad definitions that encourage flexibility and innovation in research approaches, against classification specificity that minimizes ambiguity about protocols but can hinder progress. Constructive research around tES classification, such as transcranial direct current stimulation (tDCS), should allow some variations in protocol but also distinguish from approaches that bear so little resemblance that their safety and efficacy should not be compared directly. The proposed framework includes terms in contemporary use across peer-reviewed publications, including relatively new nomenclature introduced in the past decade, such as transcranial alternating current stimulation (tACS) and transcranial pulsed current stimulation (tPCS), as well as terms with long historical use such as electroconvulsive therapy (ECT). We also define commonly used terms-of-the-trade including electrode, lead, anode, and cathode, whose prior use, in varied contexts, can also be a source of confusion. This comprehensive clarification of nomenclature and associated preliminary proposals for standardized terminology can support the development of consensus on efficacy, safety, and regulatory standards.
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http://dx.doi.org/10.1016/j.brs.2019.07.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6851475PMC
February 2020

Transcranial electrical and magnetic stimulation (tES and TMS) for addiction medicine: A consensus paper on the present state of the science and the road ahead.

Neurosci Biobehav Rev 2019 09 2;104:118-140. Epub 2019 Jul 2.

Medical University of South Carolina (MUSC), USA.

There is growing interest in non-invasive brain stimulation (NIBS) as a novel treatment option for substance-use disorders (SUDs). Recent momentum stems from a foundation of preclinical neuroscience demonstrating links between neural circuits and drug consuming behavior, as well as recent FDA-approval of NIBS treatments for mental health disorders that share overlapping pathology with SUDs. As with any emerging field, enthusiasm must be tempered by reason; lessons learned from the past should be prudently applied to future therapies. Here, an international ensemble of experts provides an overview of the state of transcranial-electrical (tES) and transcranial-magnetic (TMS) stimulation applied in SUDs. This consensus paper provides a systematic literature review on published data - emphasizing the heterogeneity of methods and outcome measures while suggesting strategies to help bridge knowledge gaps. The goal of this effort is to provide the community with guidelines for best practices in tES/TMS SUD research. We hope this will accelerate the speed at which the community translates basic neuroscience into advanced neuromodulation tools for clinical practice in addiction medicine.
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http://dx.doi.org/10.1016/j.neubiorev.2019.06.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7293143PMC
September 2019

Physical characteristics not psychological state or trait characteristics predict motion during resting state fMRI.

Sci Rep 2019 01 23;9(1):419. Epub 2019 Jan 23.

Laureate Institute for Brain Research (LIBR), Tulsa, OK, USA.

Head motion (HM) during fMRI acquisition can significantly affect measures of brain activity or connectivity even after correction with preprocessing methods. Moreover, any systematic relationship between HM and variables of interest can introduce systematic bias. There is a large and growing interest in identifying neural biomarkers for psychiatric disorders using resting state fMRI (rsfMRI). However, the relationship between HM and different psychiatric symptoms domains is not well understood. The aim of this investigation was to determine whether psychiatric symptoms and other characteristics of the individual predict HM during rsfMRI. A sample of n = 464 participants (174 male) from the Tulsa1000, a naturalistic longitudinal study recruiting subjects with different levels of severity in mood/anxiety/substance use disorders based on the dimensional NIMH Research Domain Criteria framework was used for this study. Based on a machine learning (ML) pipeline with nested cross-validation to avoid overfitting, the stacked model with 15 anthropometric (like body mass index, BMI) and demographic (age and sex) variables identifies BMI and weight as the most important variables and explained 10.9 percent of the HM variance (95% CI: 9.9-11.8). In comparison ML models with 105 self-report measures for state and trait psychological characteristics identified nicotine and alcohol use variables as well as impulsivity inhibitory control variables but explain only 5 percent of HM variance (95% CI: 3.5-6.4). A combined ML model using all 120 variables did not perform significantly better than the model using only 15 physical variables (combined model 95% confidence interval: 10.2-12.4). Taken together, after considering physical variables, state or trait psychological characteristics do not provide additional power to predict motion during rsfMRI.
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http://dx.doi.org/10.1038/s41598-018-36699-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6344520PMC
January 2019

Preliminary Normative Data of Persian Phonemic and Semantic Verbal Fluency Test.

Iran J Psychiatry 2018 Oct;13(4):288-295

Neurocognitive Laboratory, Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran.

Verbal fluency tests (VFTs) are widely used in clinical practice and research to assess executive functions and are highly sensitive to frontal lobe lesions. However, using VFTs in different cultures and languages needs further considerations. The aim of this study was to provide a Persian (Farsi) version of verbal fluency with preliminary normative data. In the first phase, 50 healthy native Persian-speaking individuals completed 1-minute VFT for all 32 letters in Persian to find letters with highest frequency. In the second phase, 100 healthy participants (50 females) were recruited into 5 age groups that were matched by gender and education. Participants were instructed to do 1-minute VFT for the 3 selected letters (phonemic VFT) and 3 categories (animal, supermarket, and fruit) (semantic VFT). For data analysis, one-way ANOVA was performed. In the first phase, 3 letters (Pe standing for /P/, Meem for /M/ and Kaaf for /K/) had the highest frequency in word production (12 in average) and had been chosen for Persian phonemic VFT. Participants were assessed with the 3 selected letters (/P/: 12.28±3.607, /M/: 12.54±3.907, and /K/: 12.48±3.708) and 3 semantic categories (animal: 21.67±5.119, supermarket: 21.19±4.907, and fruit: 19.58±4.439) with 1-minute time limitation for each test. The results showed that education was significantly (p<0.01) associated with the performance in the phonemic but not semantic scores, while age was not correlated with either of the tests. No significant effect of gender was observed. Based on our results, we recommend Persian letters Pe, Meem, and Kaff that have the highest frequency in word production among others to be used for neuropsychological assessments and future studies in the Persian language. This is the same logic behind selecting F, A, and S in the English version. Although the norms obtained in this study are preliminary, these results can be useful in clinical evaluation with considerations about age and educational levels. Moreover, the findings of this study can be used as an initial step for more comprehensive normative studies.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6320381PMC
October 2018

Oral health status and its determinants among opiate dependents: a cross-sectional study.

BMC Oral Health 2019 01 7;19(1). Epub 2019 Jan 7.

Department of Clinical Dentistry, University of Bergen, N-5020, Bergen, Norway.

Background: In addition to numerous general health problems, drug dependents manifest various oral health disorders. Our aim was to investigate the oral health status and its determinants among in-treatment opiate dependents.

Methods: As part of a comprehensive cross-sectional survey on opiate dependents admitted to methadone maintenance centers in Tehran, Iran, we conducted a clinical study in two centers from different socioeconomic areas. A trained dentist conducted face to face interviews and clinical oral examinations based on World Health Organization (WHO) criteria for Decayed, Missing, Filled Teeth (DMFT) index and Community Periodontal Index (CPI) on volunteer patients. Student's t-test, Mann-Whitney U, Kruskal Wallis, and Chi tests, in addition to linear and logistic regression models served for statistical analysis (p < 0.05).

Results: A total of 217 patients (98% men), with a mean age of 43.6 years (SD 12.3) participated in the study. Opium was the main drug of abuse reported by 70% of the participants followed by crystalline heroin (22%). Of the participants, 24.4% were totally edentulous. The mean DMFT score of participants was 20.3 (SD 7.8). Missing teeth comprised the main part of the index followed by decayed and filled teeth. Older patients (p < 0.001) and the patients with a lower socioeconomic status (p = 0.01) had higher DMFT scores. None of the dentate patients had a healthy periodontium. Maximum CPI mostly consisted of shallow pockets (66%) followed by calculus in 15%, deep pockets in 11%, and bleeding in 8% of the participants. Older participants (p = 0.02) and those who started drug abuse at a younger age (p = 0.01) were more likely to develop periodontal pockets.

Conclusions: Opiate dependents had a poor oral health status in terms of the dentition status and periodontal health. Missing teeth comprised the main part of their dental caries history and none had a healthy periodontium. Oral health care should be integrated into the package of general health services available in treatment centers.
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http://dx.doi.org/10.1186/s12903-018-0691-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6323735PMC
January 2019

Optimizing Electrode Montages of Transcranial Direct Current Stimulation for Attentional Bias Modification in Early Abstinent Methamphetamine Users.

Front Pharmacol 2018 10;9:907. Epub 2018 Aug 10.

Department of Psychology and Neurosciences, Leibniz Research Center for Working Environment and Human Factors, Dortmund, Germany.

Chronic use of most psychoactive drugs may lead to substance dependence and drug addiction. Drug addiction is a chronically relapsing disorder, and current pharmacological and behavioral therapies are not fully efficient. Attentional bias (AB) is hypothesized to have a causal contribution to substance abuse, addiction development and, maintenance. Transcranial direct current stimulation (tDCS) has been of increasing interest in the past few years as a means for modulating neuroplasticity of the human brain. Although several studies have reported promising therapeutic effects for tDCS in drug abusers, there is no consensus about optimal electrode montages and target brain regions. This study was aimed to compare effectiveness of several electrode montages in modifying AB. Ninety early-abstinent methamphetamine users were recruited from several residential drug-rehabilitation centers in Tehran province. They were randomly assigned to six groups with different electrode montages, targeting the left or right dorsolateral prefrontal cortex (DLPFC) as follows: Two conditions with anodal tDCS over the right DLPFC (return electrode placed over the left shoulder or left supraorbital ridge), three conditions with the anode positioned over the left DLPFC (return electrode over the right shoulder, right supraorbital ridge, or contralateral DLPFC), and one sham condition. Active stimulation intensity was 2 mA DC, delivered for 13 min followed by a 20-min rest and another 13 min of stimulation. The probe detection task (PDT) was performed to assess AB. The positive and negative affect scale (PANAS), and the depression anxiety stress scales (DASS) were used to assess baseline affective status before the intervention. Mixed model analysis showed that the left DLPFC/right shoulder and left DLPFC/right DLPFC montages reduced AB toward drug-cues in comparison with sham stimulation. Our findings indicate that anodal stimulation over the left DLPFC reduces AB in methamphetamine users. This study offers promising findings for further studies investigating tDCS as a clinical device to modify AB in drug users.
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http://dx.doi.org/10.3389/fphar.2018.00907DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6096722PMC
August 2018

Transcranial DC stimulation modifies functional connectivity of large-scale brain networks in abstinent methamphetamine users.

Brain Behav 2018 03 15;8(3):e00922. Epub 2018 Feb 15.

Institute for Cognitive Science Studies Tehran Iran.

Background: Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation tool suited to alter cortical excitability and activity via the application of weak direct electrical currents. An increasing number of studies in the addiction literature suggests that tDCS modulates subjective self-reported craving through stimulation of dorsolateral prefrontal cortex (DLPFC). The major goal of this study was to explore effects of bilateral DLPFC stimulation on resting state networks (RSNs) in association with drug craving modulation. We targeted three large-scale RSNs; the default mode network (DMN), the executive control network (ECN), and the salience network (SN).

Methods: Fifteen males were recruited after signing written informed consent. We conducted a double-blinded sham-controlled crossover study. Twenty-minute "real" and "sham" tDCS (2 mA) were applied over the DLPFC on two separate days in random order. Each subject received both stimulation conditions with a 1-week washout period. The anode and cathode electrodes were located over the right and left DLPFC, respectively. Resting state fMRI was acquired before and after real and sham stimulation. Subjective craving was assessed before and after each fMRI scan. The RSNs were identified using seed-based analysis and were compared using a generalized linear model.

Results: Subjective craving decreased significantly after real tDCS compared to sham stimulation ( = .03). Moreover, the analysis shows significant modulation of DMN, ECN, and SN after real tDCS compared to sham stimulation. Additionally, alteration of subjective craving score was correlated with modified activation of the three networks.

Discussion: Given the observed alteration of the targeted functional brain networks in methamphetamine users, new potentials are highlighted for tDCS as a network intervention strategy and rsfMRI as a suitable monitoring method for these interventions.
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http://dx.doi.org/10.1002/brb3.922DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5840443PMC
March 2018

Cognitive rehabilitation for individuals with opioid use disorder: A randomized controlled trial.

Neuropsychol Rehabil 2019 Sep 21;29(8):1273-1289. Epub 2017 Nov 21.

f Neurocognitive Laboratory, Iranian National Center for Addiction Studies (INCAS) , Tehran University of Medical Sciences (TUMS) , Tehran , Iran.

To examine the efficacy of cognitive rehabilitation treatment (CRT) for people with opioid use disorder who were recruited into a methadone maintenance treatment (MMT) programme. 120 male subjects were randomly assigned to (1) MMT plus CRT in two months or (2) MMT plus a control intervention. Subjects were assessed at the beginning, mid-point and post-intervention as well as at 1-, 3- and 6-month follow-up time points. : Analysis with repeated measure ANOVA showed that the CRT group performed significantly better in tests of learning, switching, processing speed, working memory and memory span. Moreover, the CRT group had significantly lower opiate use over the control group during 3-months follow-up. Analysis including only those with a history of methamphetamine use showed that the CRT group had significantly lower amphetamine use. No group differences were observed for treatment retention. : Our findings provide evidence that adding CRT as an adjunct intervention to MMT can improve cognitive performance as well as abstinence from both opiates and stimulants.
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http://dx.doi.org/10.1080/09602011.2017.1391103DOI Listing
September 2019

Changes in Effective Connectivity Network Patterns in Drug Abusers, Treated With Different Methods.

Basic Clin Neurosci 2017 Jul-Aug;8(4):285-298

Department of Nouroimaging and Analysis, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran.

Introduction: Various treatment methods for drug abusers will result in different success rates. This is partly due to different neural assumptions and partly due to various rate of relapse in abusers because of different circumstances. Investigating the brain activation networks of treated subjects can reveal the hidden mechanisms of the therapeutic methods.

Methods: We studied three groups of subjects: heroin abusers treated with abstinent based therapy (ABT) method, heroin abusers treated with Methadone Maintenance Therapy (MMT) method, and a control group. They were all scanned with functional magnetic resonance imaging (fMRI), using a 6-block task, where each block consisted of the rest-craving-rest-neutral sequence. Using the dynamic causal modeling (DCM) algorithm, brain effective connectivity network (caused by the drug craving stimulation) was quantified for all groups. In this regard, 4 brain areas were selected for this analysis based on previous findings: ventromedial prefrontal cortex (VMPFC), dorsolateral prefrontal cortex (DLPFC), amygdala, and ventral striatum.

Results: Our results indicated that the control subjects did not show significant brain activations after craving stimulations, but the two other groups showed significant brain activations in all 4 regions. In addition, VMPFC showed higher activations in the ABT group compared to the MMT group. The effective connectivity network suggested that the control subjects did not have any direct input from drug-related cue indices, while the other two groups showed reactions to these cues. Also, VMPFC displayed an important role in ABT group. In encountering the craving pictures, MMT subjects manifest a very simple mechanism compared to other groups.

Conclusion: This study revealed an activation network similar to the emotional and inhibitory control networks observed in drug abusers in previous works. The results of DCM analysis also support the regulatory role of frontal regions on bottom regions. Furthermore, this study demonstrates the different effective connectivity patterns after drug abuse treatment and in this way helps the experts in the field.
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http://dx.doi.org/10.18869/nirp.bcn.8.4.285DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5683686PMC
November 2017

Neuroscience-informed psychoeducation for addiction medicine: A neurocognitive perspective.

Prog Brain Res 2017 6;235:239-264. Epub 2017 Oct 6.

Laureate Institute for Brain Research, Tulsa, OK, United States.

Psychoeducation (PE) is defined as an intervention with systematic, structured, and didactic knowledge transfer for an illness and its treatment, integrating emotional and motivational aspects to enable patients to cope with the illness and to improve its treatment adherence and efficacy. PE is considered an important component of treatment in both medical and psychiatric disorders, especially for mental health disorders associated with lack of insight, such as alcohol and substance use disorders (ASUDs). New advancements in neuroscience have shed light on how various aspects of ASUDs may relate to neural processes. However, the actual impact of neuroscience in the real-life clinical practice of addiction medicine is minimal. In this chapter, we provide a perspective on how PE in addiction medicine can be informed by neuroscience in two dimensions: content (knowledge we transfer in PE) and structure (methods we use to deliver PE). The content of conventional PE targets knowledge about etiology of illness, treatment process, adverse effects of prescribed medications, coping strategies, family education, and life skill training. Adding neuroscience evidence to the content of PE could be helpful in communicating not only the impact of drug use but also the beneficial impact of various treatments (i.e., on brain function), thus enhancing motivation for compliance and further destigmatizing their symptoms. PE can also be optimized in its "structure" by implicitly and explicitly engaging different neurocognitive processes, including salience/attention, memory, and self-awareness. There are many interactions between these two dimensions, structure and content, in the delivery of neuroscience-informed psychoeducation (NIPE). We explore these interactions in the development of a cartoon-based NIPE to promote brain recovery during addiction treatment as a part of the brain awareness for addiction recovery initiative.
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http://dx.doi.org/10.1016/bs.pbr.2017.08.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5771228PMC
June 2018

Metacognitive Deficiency in a Perceptual but Not a Memory Task in Methadone Maintenance Patients.

Sci Rep 2017 08 1;7(1):7052. Epub 2017 Aug 1.

Cognitive Systems Laboratory, School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran.

Drug addiction has been associated with lack of insight into one's own abilities. However, the scope of metacognition impairment among drug users in general and opiate dependent individuals in particular is not fully understood. Investigating the impairments of metacognitive ability in Substance Dependent Individuals (SDIs) in different cognitive tasks could contribute to the ongoing debate over whether metacognition has domain-general or domain-specific neural substrates. We compared metacognitive self-monitoring ability of a group of SDIs during methadone maintenance treatment (n = 23) with a control group (n = 24) in a memory and a visual perceptual task. Post decision self judgements of probability of correct choice were obtained through trial by trial confidence ratings and were used to compute metacognitive ability. Results showed that despite comparable first order performance in the perceptual task, SDIs had lower perceptual metacognition than the control group. However, although SDIs had poorer memory performance, their metacognitive judgements in the memory task were as accurate as the control group. While it is commonly believed that addiction causes pervasive impairment in cognitive functions, including metacognitive ability, we observed that the impairment was only significant in one specific task, the perceptual task, but not in the memory task.
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http://dx.doi.org/10.1038/s41598-017-06707-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5539220PMC
August 2017