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Background: Nicotine and illicit stimulants are very addictive substances. Although associations between grey matter and dependence on stimulants have been frequently reported, white matter correlates have received less attention., Methods: Eleven international sites ascribed to the ENIGMA-Addiction consortium contributed data from individuals with dependence on cocaine (n = 147), methamphetamine (n = 132) and nicotine (n = 189), as well as non-dependent controls (n = 333). We compared the fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD) of 20 bilateral tracts. Also, we compared the performance of various machine learning algorithms in deriving brain-based classifications on stimulant dependence., Results: The cocaine and methamphetamine groups had lower regional FA and higher RD in several association, commissural, and projection white matter tracts. The methamphetamine dependent group additionally showed lower regional AD. The nicotine group had lower FA and higher RD limited to the anterior limb of the internal capsule. The best performing machine learning algorithm was the support vector machine (SVM). The SVM successfully classified individuals with dependence on cocaine (AUC = 0.70, p < 0.001) and methamphetamine (AUC = 0.71, p < 0.001) relative to non-dependent controls. Classifications related to nicotine dependence proved modest (AUC = 0.62, p = 0.014)., Conclusions: Stimulant dependence was related to FA disturbances within tracts consistent with a role in addiction. The multivariate pattern of white matter differences proved sufficient to identify individuals with stimulant dependence, particularly for cocaine and methamphetamine., (Copyright © 2021. Published by Elsevier B.V.)

Brain imaging studies in children with prenatal methamphetamine exposure (PME) suggest structural and functional alterations of striatal, frontal, parietal, and limbic regions. However, no longitudinal studies have investigated changes in structural connectivity during the first 2 years of formal schooling. The aim of this study was to explore the effects of PME on structural connectivity of brain networks in children over the critical first 2 years of formal schooling when foundational learning takes place. Networks are expected to gradually increase in global connectedness while segregating into defined systems. Graph theoretical analysis was used to investigate changes in structural connectivity at age 6 and 8 years in children with and without PME. While healthy control children showed increased connectivity in frontal and limbic hubs over time, children with PME showed increased connectivity in the superior parietal cortex and striatum in their global network. Furthermore, compared to control children, those with PME were characterized by less change in segregation of structural networks over time. These findings are consistent with previous work on regions implicated in children with PME, but they additionally demonstrate alterations in structural connectivity between regions that underlie primary cognitive, behavioral, and emotional development. Understanding patterns of network development during critical periods in at-risk children may inform strategies for supporting this group of children in these developmental tasks important for lifelong brain health and development., (© 2020 Wiley Periodicals, Inc.)

Background: Methamphetamine use among pregnant women has become a significant problem. Research delineating the cognitive outcomes of prenatal methamphetamine exposure (PME) in early childhood is limited, however. The aim of this study was to examine effects of PME on cognition in six-to-seven-year-old children., Methods: PME children (n=23) and unexposed controls (n=22) completed a battery of neurocognitive tests, which included the Kaufman Assessment Battery for Children, Boston Naming Test, Beery Developmental Test of Visual-Motor Integration, and Grooved Pegboard Test., Results: Independent samples t-tests revealed that PME children scored significantly worse than controls on the measures of IQ, learning and memory, confrontation naming, visual-motor integration, and fine motor coordination. Hierarchical regression analyses that included potential confounding sociodemographic, co-exposure and anthropometric variables confirmed that PME impacts negatively on cognitive performance., Conclusions: The study confirms that PME has deleterious effects on cognition in several broad cognitive domains, likely by altering underlying brain circuitry in development. These effects may be particularly pronounced at the time when children enter formal schooling. Extended follow-ups into late childhood might help elucidate the developmental trajectory of cognitive dysfunction in PME, and subsequent effects on everyday functioning., (Copyright © 2017 Elsevier Inc. All rights reserved.)

There is emerging evidence on the harmful effects of prenatal methamphetamine (MA) exposure on the structure and function of the developing brain. However, few studies have assessed white matter structural integrity in the presence of prenatal MA exposure, and results are inconsistent. This investigation thus used diffusion tensor imaging (DTI) to investigate white matter microstructure and cognitive performance in a group of prenatal MA exposed (or MA) children and controls of similar age. Seventeen MA children and 15 healthy controls (aged 6-7 years) underwent DTI and assessment of motor function and general cognitive ability. Whole brain analyses of white matter structure were performed using FSL's tract-based spatial statistics comparing fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD). Mean diffusion values were extracted from white matter regions shown to differ across groups to determine whether variations in FA predicted cognitive performance. Analyses were controlled for maternal nicotine use. MA children showed significantly lower FA as well as higher MD, RD and AD in tracts that traverse striatal, limbic and frontal regions. Abnormal FA levels in MA children were significantly associated with poorer motor coordination and general cognitive ability sub-items that relate to aspects of executive function. Our findings suggest that, consistent with previous studies in older children, there are disruptions of white matter microstructural integrity in striatal, limbic and frontal regions of young MA exposed children, with prominent cognitive implications. Future longitudinal studies may clarify how prenatal MA exposure affects white matter structural connectivity at different stages of brain maturation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The global use of methamphetamine (MA) has increased substantially in recent years, but the effect of MA on brain structure in prenatally exposed children is understudied. Here we aimed to investigate potential changes in brain volumes and cortical thickness of children with prenatal MA-exposure compared to unexposed controls. Eighteen 6-year old children with MA-exposure during pregnancy and 18 healthy controls matched for age, gender and socio-economic background underwent structural imaging. Brain volumes and cortical thickness were assessed using Freesurfer and compared using ANOVA. Left putamen volume was significantly increased, and reduced cortical thickness was observed in the left hemisphere of the inferior parietal, parsopercularis and precuneus areas of MA-exposed children compared to controls. Compared to control males, prenatal MA-exposed males had greater volumes in striatal and associated areas, whereas MA-exposed females predominantly had greater cortical thickness compared to control females. In utero exposure to MA results in changes in the striatum of the developing child. In addition, changes within the striatal, frontal, and parietal areas are in part gender dependent.

Prenatal methamphetamine exposure (PME) is a significant problem in several parts of the world and poses important health risks for the developing fetus. Research on the short- and long-term outcomes of PME is scarce, however. Here, we summarize present knowledge on the cognitive and behavioral outcomes of PME, based on a review of the neuroimaging, neuropsychology, and neuroscience literature published in the past 15 years. Several studies have reported that the behavioral and cognitive sequelae of PME include broad deficits in the domains of attention, memory, and visual-motor integration. Knowledge regarding brain-behavior relationships is poor, however, in large part because imaging studies are rare. Hence, the effects of PME on developing neurocircuitry and brain architecture remain speculative, and are largely deductive. Some studies have implicated the dopamine-rich fronto-striatal pathways; however, cognitive deficits (e.g., impaired visual-motor integration) that should be associated with damage to those pathways are not manifested consistently across studies. We conclude by discussing challenges endemic to research on prenatal drug exposure, and argue that they may account for some of the inconsistencies in the extant research on PME. Studies confirming predicted brain-behavior relationships in PME, and exploring possible mechanisms underlying those relationships, are needed if neuroscience is to address the urgency of this growing public health problem.

BackgroundNicotine and illicit stimulants are very addictive substances. Although associations between grey matter and dependence on stimulants have been frequently reported, white matter correlates have received less attention.MethodsEleven international sites ascribed to the ENIGMA-Addiction consortium contributed data from individuals with dependence on cocaine (n = 147), methamphetamine (n = 132) and nicotine (n = 189), as well as non-dependent controls (n = 333). We compared the fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD) of 20 bilateral tracts. Also, we compared the performance of various machine learning algorithms in deriving brain-based classifications on stimulant dependence.ResultsThe cocaine and methamphetamine groups had lower regional FA and higher RD in several association, commissural, and projection white matter tracts. The methamphetamine dependent group additionally showed lower regional AD. The nicotine group had lower FA and higher RD limited to the anterior limb of the internal capsule. The best performing machine learning algorithm was the support vector machine (SVM). The SVM successfully classified individuals with dependence on cocaine (AUC = 0.70, p

There is emerging evidence on the harmful effects of prenatal methamphetamine (MA) exposure on the structure and function of the developing brain. However, few studies have assessed white matter structural integrity in the presence of prenatal MA exposure, and results are inconsistent. This investigation thus used diffusion tensor imaging (DTI) to investigate white matter microstructure and cognitive performance in a group of prenatal MA exposed (or MA) children and controls of similar age. Seventeen MA children and 15 healthy controls (aged 6-7 years) underwent DTI and assessment of motor function and general cognitive ability. Whole brain analyses of white matter structure were performed using FSL's tract-based spatial statistics comparing fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD). Mean diffusion values were extracted from white matter regions shown to differ across groups to determine whether variations in FA predicted cognitive performance. Analyses were controlled for maternal nicotine use. MA children showed significantly lower FA as well as higher MD, RD and AD in tracts that traverse striatal, limbic and frontal regions. Abnormal FA levels in MA children were significantly associated with poorer motor coordination and general cognitive ability sub-items that relate to aspects of executive function. Our findings suggest that, consistent with previous studies in older children, there are disruptions of white matter microstructural integrity in striatal, limbic and frontal regions of young MA exposed children, with prominent cognitive implications. Future longitudinal studies may clarify how prenatal MA exposure affects white matter structural connectivity at different stages of brain maturation.