A coordinate-based meta-analysis comparing brain activation between attention deficit hyperactivity disorder and total sleep deprivation

Sleep and circadian disturbances in children with neurodevelopmental disorders

Sleep is essential for brain development and overall health, particularly in children with neurodevelopmental disorders (NDDs). Sleep disruptions can considerably impact brain structure and function, leading to dysfunction of neurotransmitter systems, metabolism, hormonal balance and inflammatory processes, potentially contributing to the pathophysiology of NDDs. This Review examines the prevalence, types and mechanisms of sleep disturbances in children with NDDs, including autism spectrum disorder, attention-deficit hyperactivity disorder and various genetic syndromes. Common sleep disorders in these populations include insomnia, hypersomnia, circadian rhythm disorders, sleep-related breathing disorders and parasomnias, with underlying factors often involving genetic, neurobiological, environmental and neurophysiological influences. Sleep problems such as insomnia, night awakenings and sleep fragmentation are closely linked to both internalizing symptoms such as anxiety and depression, and externalizing behaviours such as hyperactivity and aggression. Assessment of sleep in children with NDDs presents unique challenges owing to communication difficulties, comorbid conditions and altered sensory processing. The Review underscores the importance of further research to unravel the complex interactions between sleep and neurodevelopment, advocating for longitudinal studies and the identification of predictive biomarkers. Understanding and addressing sleep disturbances in NDDs is crucial for improving developmental outcomes and the overall quality of life for affected individuals and their families.

Cerebral blood flow in attention deficit hyperactivity disorder: A systematic review

BACKGROUND AND OBJECTIVES

Attention deficit hyperactivity disorder (ADHD) is one of the most frequent and disabling neurodevelopmental disorders. Recent research on cerebral blood flow (CBF) has enhanced understanding of the underlying pathophysiology in neuropsychiatric disorders. This systematic review aims to synthesize the existing literature on CBF anomalies among individuals with ADHD in comparison to controls.

METHODS

Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach, a systematic literature search was conducted using PubMed, PsycInfo, and Web of Science to identify relevant studies on CBF in ADHD.

RESULTS

Twenty studies, encompassing a total of 1652 participants with ADHD and 580 controls, were included, employing measurements from SPECT (n = 9), ASL (n = 6), PET (n = 4), and BOLD-derived quantitative maps (n = 1). In individuals with ADHD during resting state, hypoperfusion was frequently observed in the right orbitofrontal gyrus, temporal cortex, basal ganglia and putamen. Conversely, hyperperfusion was noted in frontal lobes, left postcentral gyrus, and occipital lobes. During cognitive tasks, hyperperfusion was observed in frontal areas, temporal regions, cingulate cortex and the precuneus. Furthermore, the administration of methylphenidate was associated with increased CBF in striatal and posterior periventricular regions, the right thalamus, and the precentral gyrus.

CONCLUSION

This review highlights diverse CBF anomalies in ADHD. The most consistently reported findings suggest hypoperfusion during resting state in prefrontal and temporal areas, along with the basal ganglia, while there is a hyperperfusion in frontal, parietal and occipital regions. Further research, including longitudinal studies, is essential to develop a comprehensive understanding of CBF implications in ADHD.

A multimodal neuroimaging meta-analysis of functional and structural brain abnormalities in attention-deficit/hyperactivity disorder

BACKGROUND

Numerous neuroimaging studies utilizing resting-state functional imaging and voxel-based morphometry (VBM) have identified variations in distinct brain regions among individuals with attention-deficit/hyperactivity disorder (ADHD). However, the results have been inconsistent.

METHODS

A comprehensive voxel-wise meta-analysis was performed on studies employing resting-state functional imaging and gray matter volume (GMV), examining discrepancies between individuals with ADHD and neurotypical controls (NCs). The analysis utilized the Seed-based d Mapping software.

RESULTS

A systematic review of the literature identified 21 functional imaging studies (595 ADHD and 564 controls) and 50 GMV studies (1907 ADHD and 1611 controls). In general, individuals with ADHD exhibited increased resting-state functional activity in the right parahippocampal gyrus and bilateral orbitofrontal cortex (OFC), as well as decreased resting-state functional activity in the bilateral cingulate cortex (including the posterior cingulate cortex [PCC], median cingulate cortex [MCC], and anterior cingulate cortex [ACC]). The VBM meta-analysis revealed decreased GMV in the bilateral OFC, right putamen (extending to right superior temporal gyrus [STG]), left inferior frontal gyrus (IFG), right superior frontal gyrus (SFG), ACC, and precentral gyrus among individuals with ADHD.

CONCLUSIONS

The multimodal meta-analyses indicated that individuals with ADHD exhibit abnormalities in both function and structure in the bilateral OFC. In addition, a few regions exhibited only functional or only structural abnormalities in ADHD, such as in the limbic, prefrontal, primary sensorimotor regions.

Review of Clinical Considerations in the Management of Adolescents with ADHD During Ramadan

Background:

Fasting in Ramadan, a holy month in Islam, is considered a religious obligation to Muslims after puberty. Fasting during Ramadan entails abstinence from consuming food and liquids, as well as abstaining from other activities, including smoking and sexual activity, from dawn until sunset. Literature exists regarding the management of multiple medical conditions impacted by the month of fasting; however, limited literature exists to guide the management of Attention-Deficit/Hyperactivity Disorder (ADHD) during Ramadan.

Methods:

This systematic review employed a PUBMED search which was conducted using keywords ((ADHD) AND (Muslims)) OR ((ADHD) AND (FASTING)) OR ((ADHD) AND (RAMADAN)) OR ((RAMADAN) AND (MANAGEMENT)) and search strategies to find existing literature on ADHD management during Ramadan or while fasting.

Results:

Eight hundred and sixty-one results were obtained. Of these, full texts of clinical trials, systematic reviews, reviews, randomized control trials, and metaanalyses resulted in 303 results that were screened by title or abstract for relevance to the topic. The duplicate articles were removed. Eighty-nine results were incorporated into this paper, including full articles, book excerpts, and online articles.

Discussion:

Muslim adolescents may face challenges with academic and social functioning as they navigate psychosocial changes in the context of Ramadan. ADHD management options should be discussed with individuals who are planning to fast. Pharmacologic management options include continuing on the current regimen, dose adjustment to mitigate side effect exacerbation, a change in medication class, or a change in medication formulation. For severe cases or cases with comorbid conditions, continued fasting may not be recommended. In these cases, the patient should attempt to seek counsel with their community’s religious scholar in collaboration with their medication provider. Ultimately, there are limitations in the available data, and there is a need for further investigation into the impacts of fasting during Ramadan on individuals with ADHD and the effectiveness of interventions to promote treatment adherence.

Comparison of resting-state brain activity between insomnia and generalized anxiety disorder: A coordinate-based meta-analysis

Patients with insomnia disorder (ID) usually experience a greater burden of comorbid anxiety symptoms. However, the neural mechanism under the mutual relationship between ID and anxiety remains largely unclear. The meta-analysis aimed to explore the concordance and distinction of regional brain functional activity in patients with ID and those with generalized anxiety disorder (GAD) using coordinate-based activation likelihood estimation approach. Studies using resting-state regional homogeneity, amplitude of low-frequency fluctuations (ALFF), or fractional ALFF in patients with ID or GAD were included by searching multiple databases up to May 24, 2024. Using meta-analytic approach, 21 studies of ID vs. healthy controls (HC) and 16 studies of GAD vs. HC were included to illuminate the common and distinct patterns between the two disorders. Results showed that ID and GAD shared increased brain activities in the left posterior cingulate cortex and left precuneus, as well as decreased brain activity in the left medial prefrontal cortex. Additionally, compared with ID, GAD showed greater increased activities in the left superior frontal gyrus. Our study reveals both common and different activation patterns between ID and GAD, which may provide novel insights for understanding the neural basis of the two disorders and enlighten the possibility of the development of more targeted treatment strategies for ID and GAD.

Altered Functional Connectivity in Working Memory Network After Acute Sleep Deprivation

Acute sleep deprivation (SD) has a detrimental effect on working memory (WM). However, prior functional magnetic resonance imaging (fMRI) studies have failed to reach consistent results on brain functions underlying WM decline after acute SD. Thus, we aimed to identify convergent patterns of abnormal brain functions due to WM decline after acute SD. A coordinate-based activation likelihood estimation (ALE) meta-analysis of task-state fMRI studies testing the effects of acute SD on WM was performed to construct WM network. Then 26 healthy subjects with regular sleep performed the n-back task and underwent resting-state fMRI scanning before and after 24 h of SD. The functional connectivity (FC) among these brain regions and correlations with WM performance were calculated. The ALE results displayed that SD subjects performing WM-related tasks had consistent hypoactivation in the occipital lobe, left middle occipital gyrus, parietal lobe, precuneus, inferior parietal lobule, right sub-gyral, right cuneus, right limbic lobe, and right posterior cingulate. Consistent hyperactivation was showed in the left cerebrum, including the lingual gyrus, posterior lobe, cuneus, temporal lobe, and fusiform gyrus. These identified brain regions as the seeds to construct WM network. The increased FC between the left declive and right sub-gyral, left cuneus and left lingual gyrus, and left cuneus and right post cingulate were found. Furthermore, the impaired WM performance negatively correlated with increased FC. Taken together, our findings highlight that the altered FC in WM network may be the underlying mechanisms of WM decline after acute SD.

Systematic Review: White Matter Microstructural Organization in Adolescents With Depression

Objective

A growing body of literature has focused on the neural mechanisms of depression. Our goal was to conduct a systematic review on the white matter microstructural differences in adolescents with depressive disorders vs adolescents without depressive disorders.

Method

We searched PubMed and PsycINFO for publications on August 3, 2022 (original search conducted in July 2021). The review was registered on PROSPERO (registration number: CRD42021268200), and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Eligible studies were original research papers comparing diffusion tensor/spectrum imaging findings in adolescents with vs without depression (originally ages 12-19 years, later expanded to 11-21 years). Studies were excluded if they focused on depression exclusively in the context of another condition, used only dimensional depressive symptom assessment(s), or used the same dataset as another included publication.

Results

The search yielded 575 unique records, of which 14 full-text papers were included (824 adolescents with depression and 686 without depression). The following white matter regions showed significant differences in fractional anisotropy in at least 3 studies: uncinate fasciculus, cingulum, anterior corona radiata, inferior fronto-occipital fasciculus, and corpus callosum (genu and body). Most studies reported decreased, rather than increased, fractional anisotropy in adolescents with depression. Limitations include the possibility for selective reporting bias and risk of imprecision, given the small sample sizes in some studies.

Conclusion

Our systematic review suggests aberrant white matter microstructure in limbic-cortical-striatal-thalamic circuits, and the corpus callosum, in adolescents with depression. Future research should focus on developmental trajectories in depression, identifying sources of heterogeneity and integrating findings across imaging modalities.

Genetic background to attention deficit and hyperactivity disorder and attention deficit and hyperactivity disorder symptoms at the age of 5 years: the role of sleep duration

STUDY OBJECTIVES

We studied the associations between polygenic risk score (PRS) for attention deficit and hyperactivity disorder (ADHD) and (1) ADHD symptoms in 5-year-old children, (2) sleep duration throughout childhood, and (3) the interaction between PRS for ADHD and short sleep duration relative to ADHD symptoms at 5 years.

METHODS

This study is based on the population-based CHILD-SLEEP birth cohort (N = 1420 children). PRS was used to quantitate the genetic risk for ADHD. Parent-reported ADHD symptoms at 5 years were obtained from 714 children, using the Strengths and Difficulties Questionnaire (SDQ) and the Five-to-Fifteen (FTF). Our primary outcomes were SDQ-hyperactivity and FTF-ADHD total scores. Parent-reported sleep duration was measured at 3, 8, 18, 24 months, and 5 years in the whole sample and actigraphy-based sleep duration at 2 and 24 months in a subsample.

RESULTS

PRS for ADHD associated with SDQ-hyperactivity (β = 0.214, p = .012) and FTF-ADHD total (β = 0.639, p = .011), and FTF-inattention and hyperactivity subscale scores (β = 0.315, p = .017 and β = 0.324, p = .030), but not with sleep duration at any time point. Significant interactions were found between high PRS for ADHD and parent-reported short sleep throughout childhood in FTF-ADHD total score (F = 4.28, p = .039) and FTF-inattention subscale (F = 4.66, p = .031). We did not find any significant interaction between high PRS for ADHD and actigraphy-based short sleep.

CONCLUSIONS

Parent-reported short sleep moderates the association between genetic risk of ADHD and ADHD symptoms in early childhood in the general population, so that children with short sleep, in combination with high genetic risk for ADHD, could be at highest risk for ADHD symptoms.

Sex differences in medication-naïve adults with attention-deficit/hyperactivity disorder: a counting Stroop functional MRI study

Emerging evidence supports deficits in executive functions in the fronto-striato-parietal network in individuals with attention-deficit/hyperactivity disorder (ADHD). However, most functional studies recruited men with ADHD only, leaving it unclear whether executive deficits are also demonstrated in women with ADHD. Thus, we used functional magnetic resonance imaging to examine the sex differences in a counting Stroop task that explored interference control. The sample consisted of 55 medication-naïve adults with ADHD (28 men, 27 women) and 52 healthy controls (HC, 26 men, 26 women). The Conners' Continuous Performance Test further evaluated the performance of focused attention (standard deviation of the reaction time, RTSD) and vigilance (the reaction time change across different inter-stimulus intervals, RTISI). First, for the main effect of diagnosis, compared to the HC group, the ADHD group showed less activation in the caudate nucleus and inferior frontal gyrus (IFG). Second, for the main effect of sex, no significant effects were found. Third, a diagnosis-by-sex interaction indicated that the magnitude of ADHD-HC difference was greater for women than men in the right IFG and precuneus, reflecting greater difficulties for ADHD women to resolve interference. Conversely, no significant brain activation showed greater ADHD-HC difference in men than women. Also, reduced right IFG and precuneus activation was negatively associated with the scores assessing focused attention and vigilance in ADHD women, indicating that the attentional abilities are disrupted in ADHD women. Abnormalities in the frontoparietal areas may represent the main difference between ADHD women and ADHD men.

Associations between resting state brain activity and A1 adenosine receptor availability in the healthy brain: Effects of acute sleep deprivation

Introduction

Previous resting-state fMRI (Rs-fMRI) and positron emission tomography (PET) studies have shown that sleep deprivation (SD) affects both spontaneous brain activity and A1 adenosine receptor (A1AR) availability. Nevertheless, the hypothesis that the neuromodulatory adenosinergic system acts as regulator of the individual neuronal activity remains unexplored.

Methods

Therefore, fourteen young men underwent Rs-fMRI, A1AR PET scans, and neuropsychological tests after 52 h of SD and after 14 h of recovery sleep.

Results

Our findings suggested higher oscillations or regional homogeneity in multiple temporal and visual cortices, whereas decreased oscillations in cerebellum after sleep loss. At the same time, we found that connectivity strengths increased in sensorimotor areas and decreased in subcortical areas and cerebellum.

Discussion

Moreover, negative correlations between A1AR availability and rs-fMRI metrics of BOLD activity in the left superior/middle temporal gyrus and left postcentral gyrus of the human brain provide new insights into the molecular basis of neuronal responses induced by high homeostatic sleep pressure.

Comparisons of resting-state brain activity between insomnia and schizophrenia: a coordinate-based meta-analysis

Growing evidence shows that insomnia is closely associated with schizophrenia (SCZ), but the neural mechanism under the association remains unclear. A direct comparison of the patterns of resting-state brain activities would help understand the above question. Using meta-analytic approach, 11 studies of insomnia vs. healthy controls (HC) and 39 studies of SCZ vs. HC were included to illuminate the common and distinct patterns between insomnia and SCZ. Results showed that SCZ and insomnia shared increased resting-state brain activities in frontolimbic structures including the right medial prefrontal gyrus (mPFC) and left parahippocampal gyrus. SCZ additionally revealed greater increased activities in subcortical areas including bilateral putamen, caudate and right insula and greater decreased activities in precentral gyrus and orbitofrontal gyrus. Our study reveals both shared and distinct activation patterns in SCZ and insomnia, which may provide novel insights for understanding the neural basis of the two disorders and enlighten the possibility of the development of treatment strategies for insomnia in SCZ in the future.

The effects of persistent sleep disturbances during early childhood over adolescent ADHD, and the mediating effect of attention-related executive functions: Data from the 2004 Pelotas Birth Cohort

OBJECTIVE

Investigate effects of persistent sleep disturbances during early childhood over ADHD during the adolescence, and the potential attention-related executive functions mediating this effect.

METHODS

We used data from the 2004 Pelotas Birth Cohort. Children's Sleep disturbances were reported by their mothers at 12, 24, and 48 months of age, whereas the Test-of-Everyday-Attention-for-Children (TEA-Ch) and the Development and Well Being Assessment (DAWBA) were applied at 11 years of age to evaluate attention-related executive functions and ADHD, respectively. Persistent sleep problems were defined as reporting have two or more points of difficulty to sleep, nightmares, restless sleeps, and/or <10h/24h sleep duration. Logistic regression and mediation models were used, adjusting for maternal and child sociodemographic, behavior and health related variables.

RESULTS

The highest prevalence of adolescent ADHD (15.4%) was on the group who reported having nightmares at 2,4 and 6 years. In adjusted models, we observed an odd of ADHD in the adolescence 2.26 higher in those who reported persistent nightmares (CI95% 1.33, 4.01) compared to those reported transitory or no nightmares. Persistent difficulty to sleep (OR=1.74 CI95% 1.13, 2.66) and restless sleep (OR=1.80, CI95% 1.23, 2.64) during childhood also increased ADHD odds at 11 years. No indirect effect through attention related executive functions was found using mediating models.

DISCUSSION

Persistent early sleep disturbances may increase odds of ADHD among adolescents and could be consider as early marker of such disorder, specially nightmares problems. These effects were not mediated by attention-related executive functions. Nevertheless, we had 75% of cohort inception response.

Sleep-related traits and attention-deficit/hyperactivity disorder comorbidity: Shared genetic risk factors, molecular mechanisms, and causal effects

OBJECTIVES

To evaluate the shared genetic components, common pathways and causal relationship between ADHD and sleep-related phenotypes.

METHODS

We used the largest genome-wide association summary statistics available for attention-deficit/hyperactivity disorder (ADHD) and various sleep-related phenotypes (insomnia, napping, daytime dozing, snoring, ease getting up, daytime sleepiness, sleep duration and chronotype). We estimated the genomic correlation using cross-trait linkage disequilibrium score regression (LDSR) and investigated the potential common mechanisms using gene-based cross-trait metanalyses and functional enrichment analyses. The causal effect was estimated using two-sample Mendelian randomisation (TSMR), using the inverse variance weighted method as the main estimator.

RESULTS

A positive genomic correlation between insomnia, daytime napping, daytime dozing, snoring, daytime sleepiness, short and long sleep duration, and ADHD was observed. Insomnia, daytime sleepiness, and snoring shared genes with ADHD, that are involved in neurobiological functions and regulatory signalling pathways. The TSMR supported a causal effect of insomnia, daytime napping, and short sleep duration on ADHD, and of ADHD on long sleep duration and chronotype.

CONCLUSION

Comorbidity between sleep phenotypes and ADHD may be mediated by common genetic factors that play an important role in neuronal signalling pathways. A causal effect of sleep disturbances and short sleep duration on ADHD reinforced their role as predictors of ADHD.

ENIGMA-Sleep: Challenges, opportunities, and the road map

Neuroimaging and genetics studies have advanced our understanding of the neurobiology of sleep and its disorders. However, individual studies usually have limitations to identifying consistent and reproducible effects, including modest sample sizes, heterogeneous clinical characteristics and varied methodologies. These issues call for a large-scale multi-centre effort in sleep research, in order to increase the number of samples, and harmonize the methods of data collection, preprocessing and analysis using pre-registered well-established protocols. The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) consortium provides a powerful collaborative framework for combining datasets across individual sites. Recently, we have launched the ENIGMA-Sleep working group with the collaboration of several institutes from 15 countries to perform large-scale worldwide neuroimaging and genetics studies for better understanding the neurobiology of impaired sleep quality in population-based healthy individuals, the neural consequences of sleep deprivation, pathophysiology of sleep disorders, as well as neural correlates of sleep disturbances across various neuropsychiatric disorders. In this introductory review, we describe the details of our currently available datasets and our ongoing projects in the ENIGMA-Sleep group, and discuss both the potential challenges and opportunities of a collaborative initiative in sleep medicine.

ADVIAN: Alzheimer's Disease VGG-Inspired Attention Network Based on Convolutional Block Attention Module and Multiple Way Data Augmentation

Aim: Alzheimer's disease is a neurodegenerative disease that causes 60-70% of all cases of dementia. This study is to provide a novel method that can identify AD more accurately. Methods: We first propose a VGG-inspired network (VIN) as the backbone network and investigate the use of attention mechanisms. We proposed an Alzheimer's Disease VGG-Inspired Attention Network (ADVIAN), where we integrate convolutional block attention modules on a VIN backbone. Also, 18-way data augmentation is proposed to avoid overfitting. Ten runs of 10-fold cross-validation are carried out to report the unbiased performance. Results: The sensitivity and specificity reach 97.65 ± 1.36 and 97.86 ± 1.55, respectively. Its precision and accuracy are 97.87 ± 1.53 and 97.76 ± 1.13, respectively. The F1 score, MCC, and FMI are obtained as 97.75 ± 1.13, 95.53 ± 2.27, and 97.76 ± 1.13, respectively. The AUC is 0.9852. Conclusion: The proposed ADVIAN gives better results than 11 state-of-the-art methods. Besides, experimental results demonstrate the effectiveness of 18-way data augmentation.

Relation of Decreased Functional Connectivity Between Left Thalamus and Left Inferior Frontal Gyrus to Emotion Changes Following Acute Sleep Deprivation

Objective: The thalamus is a key node for sleep-wake pathway gate switching during acute sleep deprivation (ASD), and studies have shown that it plays a certain role in emotion changes. However, there are no studies on the association between the thalamus and emotion changes in ASD. In this study, we used resting-state functional magnetic resonance imaging (R-fMRI) to explore whether changes in the functional connections between the thalamus and other brain regions are related to emotion changes and further explored the function of the thalamus under total ASD conditions.

Method: Thirty healthy, right-handed adult men underwent emotional assessment according to the Profile of Mood States Scale and R-fMRI scans before and after ASD. The correlations between changes in functional connectivity between the thalamus and other brain regions and emotion changes were then studied.

Results: Positive emotions and psychomotor performance were reduced, and negative emotions were increased following ASD. The functional connections between the left thalamus and left middle temporal gyrus, left inferior frontal gyrus, right thalamus, right inferior temporal gyrus, left middle temporal pole gyrus, right calcarine, left cuneus, left rectus and left medial superior frontal gyrus were significantly altered. Decreased functional connectivity between left thalamus and left inferior frontal gyrus related to emotion changes following ASD.

Conclusion: This study finds that functional changes in the thalamus are associated with emotion changes during ASD, suggesting that the left thalamus probably plays an essential role in emotion changes under ASD conditions.

Systematic Review and Meta-analysis: Resting-State Functional Magnetic Resonance Imaging Studies of Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

To conduct a meta-analysis of resting-state functional magnetic resonance imaging (R-fMRI) studies in children and adolescents with attention-deficit/hyperactivity disorder (ADHD) and in adults with ADHD to assess spatial convergence of findings from available studies.

METHOD

Based on a preregistered protocol in PROSPERO (CRD42019119553), a large set of databases were searched up to April 9, 2019, with no language or article type restrictions. Study authors were systematically contacted for additional unpublished information/data. Resting-state functional magnetic resonance imaging studies using seed-based connectivity (SBC) or any other method (non-SBC) reporting whole-brain results of group comparisons between participants with ADHD and typically developing controls were eligible. Voxelwise meta-analysis via activation likelihood estimation with cluster-level familywise error (voxel-level: p < .001; cluster-level: p < .05) was used.

RESULTS

Thirty studies (18 SBC and 12 non-SBC), comprising 1,978 participants (1,094 with ADHD; 884 controls) were retained. The meta-analysis focused on SBC studies found no significant spatial convergence of ADHD-related hyperconnectivity or hypoconnectivity across studies. This nonsignificant finding remained after integrating 12 non-SBC studies into the main analysis and in sensitivity analyses limited to studies including only children or only non-medication-naïve patients.

CONCLUSION

The lack of significant spatial convergence may be accounted for by heterogeneity in study participants, experimental procedures, and analytic flexibility as well as in ADHD pathophysiology. Alongside other neuroimaging meta-analyses in other psychiatric conditions, the present results should inform the conduct and publication of future neuroimaging studies of psychiatric disorders.

Cognition and Cortical Thickness in Heavy Cannabis Users

INTRODUCTION

Acute and long-term adverse effects of heavy cannabis use (HCU) on neurocognitive function have been suggested, as much as regional changes of brain volume. However, little is known about the relationship between impaired cognition and brain structure in individuals with HCU.

OBJECTIVE

Here, we investigated associations between cognition and cortical thickness (CT) in males with HCU and male controls.

METHODS

Twenty-six individuals with HCU and 20 controls were examined using a comprehensive neuropsychological test battery and high-resolution structural MRI at 3T. CT was calculated using the Computational Anatomy Toolbox (CAT12).

RESULTS

Individuals with HCU differed from controls with respect to verbal learning performance and verbal working memory only. Individuals with HCU showed reduced CT in medial temporal, orbitofrontal, and cingulate regions, as well as in areas of the middle temporal and fusiform cortex (peak voxel family-wise error-corrected p < 0.001, followed by empirically determined correction for spatial extent) compared to HC. Verbal learning performance was associated with right entorhinal and left orbitofrontal CT reductions. Entorhinal CT was also significantly associated with amount and frequency of current weekly cannabis use.

CONCLUSIONS

The data support the notion of domain-specific cognitive impairment in individuals with HCU and provide a neuromechanistic understanding of such deficits, particularly with respect to abnormal CT in brain areas associated with long-term memory processing.