Non-addicted Controls Research Articles

Enhancing response inhibition behavior through tDCS intervention in college students with smartphone addiction

Smartphone addiction, emerging from excessive use of smartphones, poses a challenge to inhibitory control functions within society. This research employed transcranial direct current stimulation (tDCS) as an intervention alongside the stop signal task (SST) to explore behavioral distinctions between individuals with smartphone addiction and a non-addicted control group, focusing on the efficacy of tDCS intervention. The participant cohort comprised 80 individuals, divided into an addiction group (39 participants, with 19 receiving active tDCS and 20 receiving sham tDCS) and a control group (41 participants, with 20 receiving active tDCS and 21 receiving sham tDCS), with anodal stimulation applied over the right dorsolateral prefrontal cortex (dlPFC) and cathodal placement over the left arm. The findings indicate that university students struggling with smartphone addiction exhibit reduced inhibitory control compared to their non-addicted peers, while maintaining similar levels of general cognitive control. Remarkably, tDCS interventions were observed to enhance inhibitory control in both groups. Although the improvement in the addiction group appeared more pronounced numerically than in the control group, no significant interaction with group was noted. However, a higher percentage of participants in the smartphone addiction (SA) group exhibited enhanced response inhibition under active tDCS. This study demonstrates the inhibitory control deficits in individuals addicted to smartphones and underscores the potential of tDCS in enhancing response inhibition. It provides a valuable reference for future tDCS research targeting smartphone addiction and highlights the importance of developing healthier smartphone usage habits.

Cocaine use disorder patients develop distinct patterns of regulation of acth secretion by a vasopressin agonist and oxytocin: Report on a laboratory study

Background: Oxytocin and Vasopressin systems in the brain sustain adaptation to stressors. Cocaine being a stressor, it may alter brain homeostatic function. This dysregulation may entrench cocaine use disorder. Method: This is a human laboratory study of the effects of intranasal desmopressin (a Vasopressin 1b receptor agonist) and oxytocin on ACTH secretion in cocaine use disorder patients versus a control group. It consisted of two endocrine challenges performed on consecutive days. On day 1, the effect of intranasal desmopressin (80 IU) on ACTH secretion was measured. On day 2, a pre-treatment with intranasal oxytocin (24 IU) preceded intranasal desmopressin to monitor its effect on desmopressin-induced ACTH secretion. We hypothesized that the effect of intranasal oxytocin in controls would differ from the effect in cocaine use disorder patients. Results: Forty-three patients were included in this study: 14 controls and 29 cocaine use disorder patients. Significant differences were noted in the direction of change of ACTH secretion between the two groups. In cocaine use disorder patients, overall ACTH secretion was on average 2.7 pg/ml/min higher after intranasal desmopressin than after intranasal oxytocin/desmopressin (t292 = 2.91, p = 0.004). The opposite was observed in controls: overall ACTH secretion averaged 3.3 pg/ml/min less after intranasal desmopressin than after intranasal oxytocin/desmopressin (t292 = -2.35, p = 0.02). Conclusion: Intranasal oxytocin and desmopressin revealed a pattern of ACTH secretion in cocaine use disorder patients that is distinct from a non-addicted control group. (ClinicalTrial.gov00255357, 10/2014)

Reduced anterior insular cortex volume in male heroin addicts: a postmortem study

We and others have observed reduced volumes of brain regions, including the nucleus accumbens, globus pallidus, hypothalamus, and habenula in opioid addiction. Notably, the insular cortex has been under increasing study in addiction, and a smaller anterior insula has been found in alcohol-addicted cases. Here, we have investigated whether similar effects occur in heroin addicts compared to healthy controls. Volumes of the anterior and posterior insula in heroin addicts (n = 14) and controls (n = 13) were assessed by morphometry of Nissl-myelin-stained serial whole-brain coronal sections. The mean relative volume of the anterior insular cortex was smaller than in non-addicted controls (3010 ± 614 *10–6 versus 3970 ± 1306 *10–6; p = 0.021). However, no significant differences in neuronal cell counts were observed. Therefore, the observed volume reduction appears to be a consequence of damaged connecting structures such as neuropil and glial cells. The findings were not confounded by age or duration of autolysis. Our results provide further evidence of structural deficits in key hubs of the addiction circuitry in heroin-dependent individuals and warrant further research in this area.

Association between Polymorphism rs1799732 of DRD2 Dopamine Receptor Gene and Personality Traits among Cannabis Dependency.

Compared to other addictive substances, patients with cannabis addiction are significantly outnumbered by those who report dependence on other, more addictive substances. Unfortunately, most cannabis addiction goes untreated, and among those who choose treatment, the requirements are much higher for adolescents and young adults. The aim of the study: To examine the relationship of cannabinoid dependency in the genetic context—the association between the rs1799732 polymorphism of the DRD2 gene and psychological traits and anxiety. Methods: The study group consisted of 515 male volunteers. Of these, 214 patients were diagnosed with cannabis addiction and 301 were non-addicted. Patients were diagnosed with NEO Five-Factor Personality Inventory (NEO-FFI), and State–Trait Anxiety Inventory (STAI) questionnaires. The interactions between personality traits and polymorphisms in the DRD2 rs1799732 gene were investigated in a group of cannabis-addicted patients and non-addicted controls using the real-time PCR method. Results: Compared to the control group, the case group obtained significantly higher scores on the STAI State, STAI Trait, Neuroticism and Openness scales, as well as lower scores on the Extraversion, Agreeableness, and Conscientiousness scales. There was no statistically significant difference between addicts and the control group in the frequency of genotypes, but there was a statistically significant difference between addicts and the control group in the frequency of the DRD2 allele rs179973. The multivariate ANOVA analysis showed a statistically significant influence of the DRD2 rs1799732 genotype on the NEO-FFI agreeableness scale and a statistically significant effect of addiction to cannabinoids or its absence on the NEO-FFI agreeableness scale score. Conclusions: Studying homogeneous subgroups—as in our study—seems reasonable, particularly when combined with genetic determinants and psychological traits. In multigenic and multifactorial entities, such a strategy has a future.

Study of Salivary Enzymes in Oral Lesions

ABSTRACT Aim and objective Saliva contains different enzymes, which reflect metabolic activities of the body. Certain enzymes, such as, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) enzymes are products of cell injury and cell death. Some benign oral conditions having malignant potential and therefore early changes in salivary enzyme level may be helpful for the early detection of malignancy. An attempt is made to compare salivary enzyme levels (AST and ALT) in benign oral lesions in tobacco addicts, malignant oral lesions in tobacco addicts, and healthy non-tobacco addict patients with age- and sex-matched control group. Material and methods A retrospective study of 150 patients with benign and malignant oral lesions with tobacco addiction was done. Control group includes tobacco non-addicts. The oral lesion was noted. Biopsy of oral lesion was sent to histopathology for diagnosis. The saliva of all patients was collected for salivary enzymes (AST and ALT) examination. Levels of salivary enzymes (AST and ALT) in benign and malignant oral lesions of patients with tobacco addiction and tobacco non-addict control group without any oral lesions with age- and sex-matched study group were included in the study. The results were analyzed statistically by Student's t-test. Results Salivary enzymes (AST and ALT) were not significantly increased in benign and malignant oral lesions in tobacco addict patients. Conclusion Salivary enzymes were increased in all benign and malignant oral lesions in tobacco consumers. There was no significant increase in salivary enzymes in all benign and malignant oral lesions in tobacco consumers. Clinical significance Research is going on salivary biomarkers, but these salivary biomarkers lack sensitivity and specificity and cannot be applied. How to cite this article Chavan RP, Ingole SM, Dalvi SM. Study of Salivary Enzymes in Oral Lesions. Int J Otorhinolaryngol Clin 2020;12(1):1–3.

Reduced habenular volumes and neuron numbers in male heroin addicts: a post-mortem study.

The Habenula is increasingly being investigated in addiction. Reduced volumes of other relevant brain regions in addiction, such as nucleus accumbens, globus pallidus and hypothalamus have been reported. Reduced volumes of the habenula as well as reduced neuronal cell count in the habenula have also been reported in mood disorders and an overlap between mood disorders and addiction is clinically widely recognized. Thus, our aim was to investigate possible volume and neuronal cell count differences in heroin addicts compared to healthy controls. Volumes of the medial (MHB) and lateral habenula (LHB) in heroin addicts (n = 12) and healthy controls (n = 12) were assessed by morphometry of 20µm serial whole brain sections. Total brain volume was larger in the heroin group (mean 1466.6 ± 58.5 cm3 vs. mean 1331.5 ± 98.8 cm3), possibly because the heroin group was about 15years younger (p = 0.001). Despite larger mean whole brain volume, the mean relative volume of the MHB was smaller than in healthy non-addicted controls (6.94 ± 2.38 × 10-6 vs.10.64 ± 3.22 × 10-6; p = 0.004). A similar finding was observed regarding relative volumes of the LHB (46.62 ± 10.90 × 10-6 vs. 63.05 ± 16.42 × 10-6 p = 0.009). In parallel, neuronal cell numbers were reduced in the MHB of heroin-addicted subjects (395,966 ± 184,178 vs. 644,149 ± 131,140; p < 0.001). These findings were not significantly confounded by age and duration of autolysis. Our results provide further evidence for brain-structural deficits in heroin addiction.

B12 and Folate Concentrations in Opium Addicts Compared to Healthy Subjects: A Case Control Study from Kerman Coronary Artery Disease Risk Study.

BackgroundOpium addiction is a global problem which has implicated many societies. Opium addiction and drug abuse is related to harmful consequences which affect life style, biochemical factors, and vitamins values, and also is considered as a risk for heart diseases. Folate and B12 levels are related to homocysteine and studies about their levels in opium addicts are controversial; therefore, we designed this study to evaluate B12 and folate values in opium addicts.MethodsFrom the Kerman Coronary Artery Disease Risk Study (KERCADRS) which is a population-based study, we randomly selected 340 men and entered them into two groups: case (n = 170) and control group (n = 170). Then vitamin B12 and folate levels were measured.FindingsOpium addiction did not change B12 and folate levels significantly in opium addicts compared to non-addict control subjects. However, only some variables including blood pressure (BP) and diabetes positively and cigarette smoking, triglyceride (TG), alcohol, and cardiovascular disease (CVD) history negatively affected folate, and none of clinical and demographic variables influenced the B12 levels (P > 0.050). TG had significant effects on B12 and folate levels although opium addiction did not show any impact.ConclusionHigh TG levels were accompanied by low levels of B12 and folate. Reduced B12 and folate values are accompanied by serum homocysteine elevation. As TG elevates in opium addicts, it can be considered as an important factor which affects vitamins levels and reduces their absorption. Opium addiction elevates homocysteine level, since we can conclude that homocysteine elevation in opium addicts is independent of B12 and folate levels.

Facebook addiction and impulsive decision-making

Introduction: This study examined the relationship between Facebook ‘addiction’ and impulsive decision-making. Impulsive decision-making, as measured by the delay discounting task, is associated with a number of addictions and other problem behaviors. Methods: We gave 75 students a paper-based packet including the Bergen Facebook Addiction Scale to measure Facebook addiction and a delay discounting task to assess one facet of impulsivity, impulsive choice. Results: When controlling for covariates, we found that those addicted to Facebook discounted delayed rewards more quickly than their non-addicted controls. Discussion: These findings suggest that those addicted to Facebook may be more impulsive than those who are not addicted to Facebook. These results may indicate that Facebook addiction shares a core characteristic (impulsivity) with other kinds of addiction and further exploration of this area is potentially warranted.

Effective brain network analysis with resting-state EEG data: a comparison between heroin abstinent and non-addicted subjects

Objective. Neuro-electrophysiological tools have been widely used in heroin addiction studies. Previous studies indicated that chronic heroin abuse would result in abnormal functional organization of the brain, while few heroin addiction studies have applied the effective connectivity tool to analyze the brain functional system (BFS) alterations induced by heroin abuse. The present study aims to identify the abnormality of resting-state heroin abstinent BFS using source decomposition and effective connectivity tools. Approach. The resting-state electroencephalograph (EEG) signals were acquired from 15 male heroin abstinent (HA) subjects and 14 male non-addicted (NA) controls. Multivariate autoregressive models combined independent component analysis (MVARICA) was applied for blind source decomposition. Generalized partial directed coherence (GPDC) was applied for effective brain connectivity analysis. Effective brain networks of both HA and NA groups were constructed. The two groups of effective cortical networks were compared by the bootstrap method. Abnormal causal interactions between decomposed source regions were estimated in the 1–45 Hz frequency domain. Main results. This work suggested: (a) there were clear effective network alterations in heroin abstinent subject groups; (b) the parietal region was a dominant hub of the abnormally weaker causal pathways, and the left occipital region was a dominant hub of the abnormally stronger causal pathways. Significance. These findings provide direct evidence that chronic heroin abuse induces brain functional abnormalities. The potential value of combining effective connectivity analysis and brain source decomposition methods in exploring brain alterations of heroin addicts is also implied.

Serum ionic dysequilibria in clinical opioid dependence: Cross-sectional and longitudinal studies.

Despite an increasing awareness that the activity of excitable membranes is determined by the underlying ionic gradients across them, and their importance in drug dependency, we were not able to identify any reports of comparing the electrolyte composition of opioid-dependent and non-addicted controls. Linear regression was used to compare clinical pathology blood results taken from 2699 opioid-dependent patients (ODP) and 5307 medical control (MC) patients on a total of 21,734 occasions for the period 1995-2015. The presence of a hepatitis C antibody test was used to separate OPD and MC patients. The mean age among ODP and MC was 33.51 ± 0.16 and 37.99 ± 0.23 years, respectively ( p < 0.0001). The groups were 71.5% and 54.2% male ( p < 0.0001). Drug use in this cohort has been reported previously. Analysis of sodium, haemoglobin and albumin were used to exclude marked effects of haemodilution/haemoconcentration. Repeated measures linear regression against age and time showed depressed levels of bicarbonate ( p < 0.0001) and potassium ( p < 0.05) and elevated levels of chloride ( p < 0.025) and anions ( p < 0.01) in ODP in both sexes. Multiple regression in mixed-effects models showed that these effects were all worse in females ( p = 0.0001). This data shows that opioid dependence is associated with significant changes in chloride, potassium, bicarbonate and anions in both sexes, and worse in females. This likely has implications for the electrophysiological properties of excitable membranes. It is consistent with the reported impairment of potassium-chloride exchangers in opioid dependence. Explication of the mechanisms responsible must await further studies.

Evaluation of a Predictive Algorithm that Detects Aberrant Use of Opioids in an Addiction Treatment Centre

Introduction: Physicians prescribing opioids are at the front lines of the opioid abuse epidemic, battling to tip the scale between rising abuse rates and adequate pain control. This study evaluates the performance of an algorithm that incorporates genetic and non-genetic risk factors in accurately predicting patients at risk of Opioid Use Disorder (OUD). Materials and methods: In this study, we evaluated the ability of the Proove Opioid Risk (POR) algorithm to correctly identify OUD in patients at an addiction treatment facility versus healthy, non-addicted controls. The algorithm was applied to 186 participants: 94 patients at an addiction treatment facility who had documented opioid abuse and 92 healthy patients with no history of opioid use. OUD cases were diagnosed by an expert addictionologist using a predetermined set of criteria, including demonstrated tolerance to an opioid, dependence on an opioid for at least one year, and history of self-administration of an opioid on a daily basis. The performance of the POR using sensitivity, specificity, positive and negative predictive values, and area under the curve (AUC) measures was assessed in OUD cases versus the healthy controls. Results: The average POR score of patients with diagnosed OUD was significantly greater than those of the controls. The receiver operator characteristic (ROC) curve of the POR had an area under the curve (AUC) of 0.967, indicating the algorithm correctly categorizes those with OUD nearly 97% of the time. The sensitivity of the algorithm was 98% and the specificity was 100%, demonstrating that the POR is very unlikely to misclassify true positives and true negatives in this study. Conclusion: The POR reliably identified OUD in patients who were addicted to opioids, while classifying healthy controls as low risk. This can be used clinically to predict patients at high risk of OUD before prescribing opioid pain medications.

Everyday problems with executive dysfunction and impulsivity in adults recovering from methamphetamine addiction.

Compared with non-addicted controls (CTLs), adults in remission from methamphetamine addiction (MA-REM) evidence impairments on objective measures of executive functioning and impulsivity. To evaluate the impact of these impairments in MA-REM adults, demographically matched groups (MA-REM, n=30; CTLs, n=24) completed objective and self-report measures of executive functioning and impulsivity. MA-REM adults demonstrated significantly (p < 0.050) greater objective and subjective problems with executive functioning and impulsivity. These results suggest that adults in MA-REM are aware of their deficits and that these deficits have significant impact in everyday life.

Neuroscience of inhibition for addiction medicine: from prediction of initiation to prediction of relapse.

A core deficit in drug addiction is the inability to inhibit maladaptive drug-seeking behavior. Consistent with this deficit, drug-addicted individuals show reliable cross-sectional differences from healthy nonaddicted controls during tasks of response inhibition accompanied by brain activation abnormalities as revealed by functional neuroimaging. However, it is less clear whether inhibition-related deficits predate the transition to problematic use, and, in turn, whether these deficits predict the transition out of problematic substance use. Here, we review longitudinal studies of response inhibition in children/adolescents with little substance experience and longitudinal studies of already addicted individuals attempting to sustain abstinence. Results show that response inhibition and its underlying neural correlates predict both substance use outcomes (onset and abstinence). Neurally, key roles were observed for multiple regions of the frontal cortex (e.g., inferior frontal gyrus, dorsal anterior cingulate cortex, and dorsolateral prefrontal cortex). In general, less activation of these regions during response inhibition predicted not only the onset of substance use, but interestingly also better abstinence-related outcomes among individuals already addicted. The role of subcortical areas, although potentially important, is less clear because of inconsistent results and because these regions are less classically reported in studies of healthy response inhibition. Overall, this review indicates that response inhibition is not simply a manifestation of current drug addiction, but rather a core neurocognitive dimension that predicts key substance use outcomes. Early intervention in inhibitory deficits could have high clinical and public health relevance.

Abnormal gray matter volume and resting-state functional connectivity in former heroin-dependent individuals abstinent for multiple years.

Previous studies have suggested that heroin addiction is associated with structural and functional brain abnormalities. However, it is largely unknown whether these characteristics of brain abnormalities would be persistent or restored after long periods of abstinence. Considering the very high rates of relapse, we hypothesized that there may exist some latent neural vulnerabilities in abstinent heroin users. In this study, structural and resting-state functional magnetic resonance imaging data were collected from 30 former heroin-dependent (FHD) subjects who were drug free for more than 3 years and 30 non-addicted control (CN) volunteers. Voxel-based morphometry was used to identify possible gray matter volume differences between the FHD and CN groups. Alterations in resting-state functional connectivity in FHD were examined using brain areas with gray matter deficits as seed regions. Significantly reduced gray matter volume was observed in FHD in an area surrounding the parieto-occipital sulcus, which included the precuneus and cuneus. Functional connectivity analyses revealed that the FHD subjects showed reduced positive correlation within the default mode network and visual network and decreased negative correlation between the default mode network, visual network and task positive network. Moreover, the altered functional connectivity was correlated with self-reported impulsivity scores in the FHD subjects. Our findings suggest that disruption of large-scale brain systems is present in former heroin users even after multi-year abstinence, which could serve as system-level neural underpinnings for behavioral dysfunctions associated with addiction.

Alterations in brain connectivity in three sub-regions of the anterior cingulate cortex in heroin-dependent individuals: Evidence from resting state fMRI

Previous studies that utilized task-based approaches have demonstrated that the chronic use of heroin is associated with altered activity of the anterior cingulate cortex (ACC). However, few studies have focused on examining the variation in resting-state functional connectivity in heroin-dependent individuals, which might help further understanding the mechanisms underlying heroin addiction. Due to the structural and functional heterogeneity of the ACC, we systematically mapped the resting-state functional connectivity patterns of three sub-regions of the ACC in heroin-dependent individuals, wondered whether the partition of three sub-regions of the ACC is feasible in heroin-dependent individuals, and identified how heroin affected the correlated activities among three sub-regions of the ACC using resting-state functional magnetic resonance imaging (fMRI). In the present study, fMRI data were acquired from 21 heroin-dependent individuals (Her group) and 15 non-addicted controls (CN group). Compared to controls, there were reduced functional connectivities in the dorsal ACC (dACC) and rostral ACC (rACC) networks with different areas of the dorsal striatum (the caudate and the putamen) in the Her group. Meanwhile, there exhibited an inverted alteration of pattern for orbital frontal cortex (OFC) and superior frontal gyrus (SFG) in the functional connectivity network with the dACC and subcallosal ACC (sACC), and a different alteration of the cerebellum and the amygdala in the functional connectivity network with the rACC and the sACC. In addition, we also found reduced connectivities between dACC and rACC, as well as reduced connectivities between sACC and dACC. Our findings of variations of functional connectivities in three sub-regions of ACC in Her group implied that these sub-regions of the ACC together with other key brain areas (such as dorsal striatum, OFC, SFG, cerebellum, amygdale, etc.) might potentially play independent and/or overlapping roles in heroin addiction, which might indicate the potential direction of future research.

Religious/Spiritual Well-Being, Coping Styles, and Personality Dimensions in People With Substance Use Disorders

Religiosity and spirituality have been found to be negatively associated with a range of addictions. It has been suggested that religious/spiritual well-being might play an important role in the development, course, and recovery from addictive disorders. A sample of addiction in-patients (N = 389) was assessed using the Multidimensional Inventory for Religious/Spiritual Well-Being (MI-RSWB) and compared with a matched group of nonaddicted community controls (N = 389). RSWB was found to be substantially lower in people with substance use disorders compared to the normal sample. Discriminate functional analysis showed that Experiences of Sense and Meaning, General Religiosity, and Forgiveness were the dimensions of RSWB that strongly distinguished the groups. Within the group of people with substance use disorders, RSWB was strongly positively associated with the personality dimensions of Conscientiousness, Agreeableness, and Openness as well as Sense of Coherence and positive Coping styles. The study suggests that therapeutic intervention programs focusing on building a positive and meaningful personal framework, akin to that of a religious/spiritual orientation, may contribute to positive outcomes in addiction treatment.

The date-delay framing effect in temporal discounting depends on substance abuse

In the present study, individuals with substance use disorders (n=30) and non-addicted controls (n=30) were presented with a delay-discounting task with time being described either as dates or as temporal intervals. Three main results were obtained. First, in both groups reward size had a large impact on discounting future rewards, with discount rates becoming larger with smaller reward sizes. Second, participants discounted future rewards less strongly when their time of delivery was presented as a date instead of a temporal distance. Third, whereas discount rates of individuals with substance use disorders varied substantially with regard to the presentation of time in the task, the controls changed their choices depending on time presentation only slightly.

The effect of methadone on emotional reactivity

Opioids have been implicated in emotion regulation. Opioid users report decreased negative emotional response, but there has been no formal study on the effect of opioid administration on emotional reactivity. The aim of this study was to investigate the effect of methadone on emotional reactivity in methadone-maintained patients. Velten's mood induction procedures were used to induce elative and depressive emotional reactions in the subjects. Each group was administered both induction procedures at 0 hour and 3 hours (corresponding with trough and peak plasma methadone concentrations in methadone subjects). A drug treatment clinic with an out-patient methadone maintenance treatment programme. Twenty-one subjects currently on methadone maintenance treatment and 21 controls with no history of opioid dependence. Emotional reactivity was measured using mood visual analogue scales. At 0 hour, methadone and control subjects showed similar elation (methadone 13.2 ± 3.1 mean ± standard error of the mean [SEM], control 14.4 ± 3.7) and depression reactivity (methadone 23.6 ± 5.0, control 25.1 ± 5.0). However, at 3 hours repeated measures showed that methadone subjects had significantly decreased depression reactivity (methadone 18.5 ± 4.6, control 36.7 ± 5.7; P = 0.021) and elation reactivity (methadone 4.4 ± 1.9, control 19.0 ± 2.4) compared to controls. Opioid addicts on methadone maintenance appear to be less reactive to mood induction at times of peak plasma methadone concentration than non-addict controls; this suggests that methadone blunts both elative and depressive emotional reactivity.

Amplitude low-frequency oscillation abnormalities in the heroin users: A resting state fMRI study

Functional neuroimaging studies have revealed abnormal functional organization of the heroin users' brain, including reward circuit, cognitive control circuit, memory circuit, motivation and salience evaluation circuits and so on. In the current study, we aimed to explore the functional changes in the regional brain of heroin users using the amplitude of low-frequency oscillations in the Blood Oxygenation Level Dependent (BOLD) signals. With fMRI data acquired during resting state from 24 chronic heroin users (all subjects were being treated with methadone) and 24 non-addicted controls, we investigated addiction related altered in the amplitude low-frequency fluctuate (ALFF) between the two groups. Compared with controls, we found that heroin addicts had decreased ALFF in the bilateral dorsal anterior cingulate cortex (dACC), bilateral medial orbit frontal cortex (mOFC), left dorsal lateral prefrontal cortex (dlPFC), left middle temporal gyrus, left inferior temporal gyrus, posterior cingulate cortex and left cuneus as well as increased ALFF in the bilateral angular gyrus, bilateral precuneus, bilateral supramarginal gyrus, left post cingulate cortex and left middle frontal gyrus. Moreover, we also found that the increased ALFF in the bilateral parietal lobe had a significantly positive correlation with the methadone does, thus we inferred that the reduced ALFF may due to heroin consumption, nevertheless, the increased ALFF in the bilateral parietal lobe may have resulted from the methadone treatment. This resting-state fMRI study suggests that the changed spontaneous neuronal activity of these regions may be implicated in the underlying pathophysiology of heroin addicts.

Comparison of Childhood Sexual Histories in Subjects with Pedophilia or Opiate Addiction and Healthy Controls

Given the recent interest in the concept of sexual addictions, it is instructive to study subjects with pedophilia alongside chemically addicted individuals and non-addicted controls in order to help identify which factors may determine the objects of people's respective addictions, as well as any factors that may predispose people to developing an addictive disorder. In this study, we considered whether childhood sexual abuse (CSA) is a specific risk factor for pedophilia as opposed to other types of addictive disorders by comparing the childhood sexual histories of 48 pedophilic sex offenders, 25 subjects with opiate addiction in remission, and 61 healthy controls. CSA was assessed with The Sexual History Questionnaire and the Child Trauma Questionnaire (CTQ). Compared with both opiate addicted subjects and healthy controls, subjects with pedophilia were more likely to report experiencing adult sexual advances when they were children and a first sexual contact by age 13 with a partner at least 5 years older. Although both subjects with pedophilia and those with opiate addiction first had sex at a younger age than healthy controls, opiate addicted subjects, compared with healthy controls, reported neither increased reception of sexual advances as children nor increased rates of first sexual contact before age 13 with a partner at least 5 years older. Further, subjects with pedophilia but not those with opiate addiction scored significantly higher than healthy controls on the CTQ. Sexual abuse in childhood may be a specific risk factor for sexual addictions such as pedophilia but may not be a specific risk factor for chemical addictions.