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Decreased information processing speed and decision-making performance in alcohol use disorder: combined neurostructural evidence from VBM and TBSS. Brain Imaging Behav 2021; 15:205-215. [PMID: 32124275 DOI: 10.1007/s11682-019-00248-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Alcohol Use Disorder (AUD) is a chronic relapsing condition characterized by excessive alcohol consumption despite its multifaceted adverse consequences, associated with impaired performance in several cognitive domains including decision-making. While choice deficits represent a core component of addictive behavior, possibly consecutive to brain changes preceding the onset of the addiction cycle, the evidence on grey-matter and white-matter damage underlying abnormal choices in AUD is still limited. To fill this gap, we assessed the neurostructural bases of decision-making performance in 22 early-abstinent alcoholic patients and 18 controls, by coupling the Cambridge Gambling Task (CGT) with quantitative magnetic resonance imaging metrics of grey-matter density and white-matter integrity. Regardless of group, voxel based morphometry highlighted an inverse relationship between deliberation time and grey-matter density, with alcoholics displaying slower choices related to grey-matter atrophy in key nodes of the motor control network. In particular, grey-matter density in the supplementary motor area, reduced in alcoholic patients, explained a significant amount of variability in their increased deliberation time. Tract-based spatial statistics revealed a significant relationship between CGT deliberation time and all white-matter indices, involving the most relevant commissural, projection and associative tracts. The lack of choice impairments other than increased deliberation time highlights reduced processing speed, mediated both by grey-matter and white-matter alterations, as a possible marker of a generalized executive impairment extending to the output stages of decision-making. These results pave the way to further studies aiming to tailor novel rehabilitation strategies and assess their functional outcomes.
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Visuoperceptive Impairments in Severe Alcohol Use Disorder: A Critical Review of Behavioral Studies. Neuropsychol Rev 2021; 31:361-384. [PMID: 33591477 DOI: 10.1007/s11065-020-09469-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 11/29/2020] [Indexed: 01/13/2023]
Abstract
The present literature review is aimed at offering a comprehensive and critical view of behavioral data collected during the past seventy years concerning visuoperception in severe alcohol use disorders (AUD). To pave the way for a renewal of research and clinical approaches in this very little understood field, this paper (1) provides a critical review of previous behavioral studies exploring visuoperceptive processing in severe AUD, (2) identifies the alcohol-related parameters and demographic factors that influence the deficits, and (3) addresses the limitations of this literature and their implications for current clinical strategies. By doing so, this review highlights the presence of visuoperceptive deficits but also shows how the lack of in-depth studies exploring the visual system in this clinical population results in the current absence of integration of these deficits in the dominant models of vision. Given the predominance of vision in everyday life, we stress the need to better delineate the extent, the specificity, and the actual implications of the deficits for severe AUD.
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Creupelandt C, D'Hondt F, Maurage P. Neural correlates of visuoperceptive changes in severe alcohol use disorder: A critical review of neuroimaging and electrophysiological findings. J Neurosci Res 2021; 99:1253-1275. [PMID: 33550638 DOI: 10.1002/jnr.24799] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/04/2021] [Accepted: 01/06/2021] [Indexed: 01/04/2023]
Abstract
Visuoperceptive deficits are frequently reported in severe alcohol use disorder (SAUD) and are considered as pervasive and persistent in time. While this topic of investigation has previously driven researchers' interest, far fewer studies have focused on visuoperception in SAUD since the '90s, leaving open central questions regarding the origin and implications of these deficits. To renew research in the field and provide a solid background to work upon, this paper reviews the neural correlates of visuoperception in SAUD, based on data from neuroimaging and electrophysiological studies. Results reveal structural and functional changes within the visual system but also in the connections between occipital and frontal areas. We highlight the lack of integration of these findings in the dominant models of vision which stress the dynamic nature of the visual system and consider the presence of both bottom-up and top-down cerebral mechanisms. Visuoperceptive changes are also discussed in the framework of long-lasting debates regarding the influence of demographic and alcohol-related factors, together stressing the presence of inter-individual differences. Capitalizing on this review, we provide guidelines to inform future research, and ultimately improve clinical care.
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Affiliation(s)
- Coralie Creupelandt
- Louvain Experimental Psychopathology Research Group (UCLEP), Faculté de Psychologie, Psychological Sciences Research Institute (IPSY), UCLouvain, Louvain-la-Neuve, Belgium
| | - Fabien D'Hondt
- Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France.,CHU Lille, Clinique de Psychiatrie, CURE, Lille, France.,Centre National de Ressources et de Résilience Lille-Paris (CN2R), Lille, France
| | - Pierre Maurage
- Louvain Experimental Psychopathology Research Group (UCLEP), Faculté de Psychologie, Psychological Sciences Research Institute (IPSY), UCLouvain, Louvain-la-Neuve, Belgium
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Gonthier C. Charting the Diversity of Strategic Processes in Visuospatial Short-Term Memory. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2020; 16:294-318. [PMID: 33048607 DOI: 10.1177/1745691620950697] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Despite the abundant literature on visuospatial short-term memory, researchers have devoted little attention to strategic processes: What procedures do subjects implement to memorize visuospatial material? Evidence for various strategies exists, but it is spread across a variety of fields. This integrative review of the literature brings together scattered evidence to provide an overview of strategic processes in visuospatial memory tasks. The diversity of strategies and their proposed operating mechanisms are reviewed and discussed. The evidence leads to proposing seven broad strategic processes used in visuospatial short-term memory, each with multiple variants. Strategies can vary across individuals, but the same subjects also appear to use multiple strategies depending on the perceptual features of to-be-remembered displays. These results point to a view of visuospatial strategies as a functional library of facilitatory processes on which subjects can draw to support visuospatial short-term memory performance. Implications are discussed for the difference between visual and spatial tasks, for the appropriate measurement of strategic behaviors, and for the interpretation of performance in visuospatial memory tasks.
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Affiliation(s)
- Corentin Gonthier
- Laboratoire de Psychologie: Cognition, Comportement, Communication (LP3C), Equipe d'Accueil 1285, Université Rennes 2
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Yun JY, Jang JH, Jung WH, Shin NY, Kim SN, Hwang JY, Kwon JS. Executive Dysfunction in Obsessive-Compulsive Disorder and Anterior Cingulate-Based Resting State Functional Connectivity. Psychiatry Investig 2017; 14:333-343. [PMID: 28539952 PMCID: PMC5440436 DOI: 10.4306/pi.2017.14.3.333] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 05/03/2016] [Accepted: 05/06/2016] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE Executive dysfunction might be an important determinant for response to pharmacotherapy in obsessive-compulsive disorder (OCD), and could be sustained independently of symptom relief. The anterior cingulate cortex (ACC) has been indicated as a potential neural correlate of executive functioning in OCD. The present study examined the brain-executive function relationships in OCD from the ACC-based resting state functional connectivity networks (rs-FCNs), which reflect information processing mechanisms during task performance. METHODS For a total of 58 subjects [OCD, n=24; healthy controls (HCs), n=34], four subdomains of executive functioning were measured using the Rey-Osterrieth Complex Figure Test (RCFT), the Stroop Color-Word Test (SCWT), the Wisconsin Card Sorting Test (WCST), and the Trail Making Test part B (TMT-B). To probe for differential patterns of the brain-cognition relationship in OCD compared to HC, the ACC-centered rs-FCN were calculated using five seed regions systemically placed throughout the ACC. RESULTS Significant differences between the OCD group and the HCs with respect to the WCST perseverative errors, SCWT interference scores, and TMT-B reaction times (p<0.05) were observed. Moreover, significant interactions between diagnosis×dorsal ACC [S3]-based rs-FCN strength in the right dorsolateral prefrontal cortex for RCFT organization summary scores as well as between diagnosis×perigenual ACC [S7]-based rs-FCN strength in the left frontal eye field for SCWT color-word interference scores were unveiled. CONCLUSION These network-based neural foundations for executive dysfunction in OCD could become a potential target of future treatment, which could improve global domains of functioning broader than symptomatic relief.
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Affiliation(s)
- Je-Yeon Yun
- Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Joon Hwan Jang
- Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Wi Hoon Jung
- Institute of Human Behavioral Medicine, SNU-MRC, Seoul, Republic of Korea
| | - Na Young Shin
- Institute of Human Behavioral Medicine, SNU-MRC, Seoul, Republic of Korea
| | - Sung Nyun Kim
- Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jae Yeon Hwang
- Institute of Human Behavioral Medicine, SNU-MRC, Seoul, Republic of Korea
| | - Jun Soo Kwon
- Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea
- Institute of Human Behavioral Medicine, SNU-MRC, Seoul, Republic of Korea
- Department of Brain & Cognitive Sciences, College of Natural Science, Seoul National University, Seoul, Republic of Korea
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Zahr NM, Pfefferbaum A, Sullivan EV. Perspectives on fronto-fugal circuitry from human imaging of alcohol use disorders. Neuropharmacology 2017; 122:189-200. [PMID: 28118989 DOI: 10.1016/j.neuropharm.2017.01.018] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 01/18/2017] [Accepted: 01/19/2017] [Indexed: 01/18/2023]
Abstract
Descriptions of the cognitive functions affected by alcohol use disorders (AUD) often highlight dysfunction of executive processes such attention, inhibitory control, working memory, and cognitive flexibility. Such complex cognitive functions have historically been ascribed to the prefrontal cortex. AUD, however, disrupts extensive areas of the brain. Structural and functional MRI studies suggest a central role for degradation of circuitry originating in the prefrontal cortex including nodes in widespread brain regions. This review features fronto-fugal circuits affected by AUD including frontocerebellar, frontolimbic, and frontostriatal networks and their relations to the salient, enduring, and debilitating cognitive and motor deficits reported in AUD. This article is part of the Special Issue entitled "Alcoholism".
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Affiliation(s)
- Natalie M Zahr
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 401 Quarry Rd., Stanford, CA 94305, USA; Neuroscience Department, SRI International, 333 Ravenswood Ave., Menlo Park, CA 94025, USA.
| | - Adolf Pfefferbaum
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 401 Quarry Rd., Stanford, CA 94305, USA; Neuroscience Department, SRI International, 333 Ravenswood Ave., Menlo Park, CA 94025, USA
| | - Edith V Sullivan
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 401 Quarry Rd., Stanford, CA 94305, USA
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Li K, Zhang Y, Ning Y, Zhang H, Liu H, Fu C, Ren Y, Zou Y. The effects of acupuncture treatment on the right frontoparietal network in migraine without aura patients. J Headache Pain 2015; 16:518. [PMID: 25916336 PMCID: PMC4411327 DOI: 10.1186/s10194-015-0518-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 04/14/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Functional and structural abnormalities in resting-state brain networks in migraine patients have been confirmed by previous functional magnetic resonance imaging (fMRI) studies. However, few studies focusing on the neural responses of therapeutic treatment on migraine have been conducted. In this study, we tried to examined the treatment-related effects of standard acupuncture treatment on the right frontoparietal network (RFPN) in migraine patients. METHODS A total of 12 migraine without aura (MWoA) patients were recruited to undergo resting-state fMRI scanning and were rescanned after 4 weeks standard acupuncture treatment. Another 12 matched healthy control (HC) subjects underwent once scanning for comparison. We analyzed the functional connectivity of the RFPN between MWoA patients and HC subjects before treatment and that of the MWoA patients before and after treatment. Diffusion tensor images (DTI) data analyzing was also performed to detect fiber-related treatment responses. RESULTS We observed significantly decreased FC in the RFPN and that the decreased FC could be reversed by acupuncture treatment. The changes of FC in MWoA patients was negatively correlated with the decrease of visual analogue scale (VAS) scores after treatment. This study indicated that acupuncture treatment for MWoA patients was associated with normalizing effects on the intrinsic decreased FC of the RFPN. CONCLUSIONS Our study provided new insights into the treatment-related neural responses in MWoA patients and suggested potential functional pathways for the evaluation of treatment in MWoA patients. Future studies are still in need to confirm the current results and to elucidate the complex neural mechanisms of acupuncture treatment.
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Affiliation(s)
- Kuangshi Li
- Department of Neurology and Stroke Center, Dongzhimen Hospital, The First Affiliated Hospital of Beijing University of Chinese Medicine, Beijing, 100700, China,
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Monnig MA, Thayer RE, Caprihan A, Claus ED, Yeo RA, Calhoun VD, Hutchison KE. White matter integrity is associated with alcohol cue reactivity in heavy drinkers. Brain Behav 2014; 4:158-70. [PMID: 24683509 PMCID: PMC3967532 DOI: 10.1002/brb3.204] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 11/17/2013] [Accepted: 11/25/2013] [Indexed: 02/07/2023] Open
Abstract
Neuroimaging studies have shown that white matter damage accompanies excessive alcohol use, but the functional correlates of alcohol-related white matter disruption remain unknown. This study applied tract-based spatial statistics (TBSS) to diffusion tensor imaging (DTI) data from 332 heavy drinkers (mean age = 31.2 ± 9.4; 31% female) to obtain averaged fractional anisotropy (FA) values of 18 white matter tracts. Statistical analyses examined correlations of FA values with blood-oxygenation-level-dependent (BOLD) response to an alcohol taste cue, measured with functional magnetic resonance imaging (fMRI). FA values of nine white matter tracts (anterior corona radiata, body of corpus callosum, cingulate gyrus, external capsule, fornix, inferior frontooccipital fasciculus, posterior corona radiata, retrolenticular limb of internal capsule, and superior longitudinal fasciculus) were significantly, negatively correlated with BOLD activation in medial frontal gyrus, parahippocampal gyrus, fusiform gyrus, cingulum, thalamus, caudate, putamen, insula, and cerebellum. The inverse relation between white matter integrity and functional activation during the alcohol taste cue provides support for the hypothesis that lower white matter integrity in frontoparietal and corticolimbic networks is a factor in loss of control over alcohol consumption.
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Affiliation(s)
- Mollie A Monnig
- Mind Research Network Albuquerque, 87106, New Mexico ; University of New Mexico Albuquerque, 87106, New Mexico
| | | | | | - Eric D Claus
- Mind Research Network Albuquerque, 87106, New Mexico ; University of New Mexico Albuquerque, 87106, New Mexico
| | - Ronald A Yeo
- Mind Research Network Albuquerque, 87106, New Mexico ; University of New Mexico Albuquerque, 87106, New Mexico
| | - Vince D Calhoun
- Mind Research Network Albuquerque, 87106, New Mexico ; University of New Mexico Albuquerque, 87106, New Mexico
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Oscar-Berman M, Valmas MM, Sawyer KS, Ruiz SM, Luhar RB, Gravitz ZR. Profiles of impaired, spared, and recovered neuropsychologic processes in alcoholism. HANDBOOK OF CLINICAL NEUROLOGY 2014; 125:183-210. [PMID: 25307576 PMCID: PMC4515358 DOI: 10.1016/b978-0-444-62619-6.00012-4] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Long-term chronic alcoholism is associated with disparate and widespread residual consequences for brain functioning and behavior, and alcoholics suffer a variety of cognitive deficiencies and emotional abnormalities. Alcoholism has heterogeneous origins and outcomes, depending upon factors such as family history, age, gender, and mental or physical health. Consequently, the neuropsychologic profiles associated with alcoholism are not uniform among individuals. Moreover, within and across research studies, variability among subjects is substantial and contributes to characteristics associated with differential treatment outcomes after detoxification. In order to refine our understanding of alcoholism-related impaired, spared, and recovered abilities, we focus on five specific functional domains: (1) memory; (2) executive functions; (3) emotion and psychosocial skills; (4) visuospatial cognition; and (5) psychomotor abilities. Although the entire brain might be vulnerable in uncomplicated alcoholism, the brain systems that are considered to be most at risk are the frontocerebellar and mesocorticolimbic circuitries. Over time, with abstinence from alcohol, the brain appears to become reorganized to provide compensation for structural and behavioral deficits. By relying on a combination of clinical and scientific approaches, future research will help to refine the compensatory roles of healthy brain systems, the degree to which abstinence and treatment facilitate the reversal of brain atrophy and dysfunction, and the importance of individual differences to outcome.
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Affiliation(s)
- Marlene Oscar-Berman
- Boston University School of Medicine, L-815, 72 E. Newton St., Boston, MA 02118; ; telephone 617-638-4803
| | - Mary M. Valmas
- Boston University School of Medicine, L-815, 72 E. Newton St., Boston, MA 02118; ; telephone 617-638-4803
| | - Kayle S. Sawyer
- Boston University School of Medicine, L-815, 72 E. Newton St., Boston, MA 02118; ; telephone 617-638-4803
| | - Susan Mosher Ruiz
- Boston University School of Medicine, L-815, 72 E. Newton St., Boston, MA 02118; ; telephone 617-638-4803
| | - Riya B. Luhar
- Boston University School of Medicine, L-815, 72 E. Newton St., Boston, MA 02118; ; telephone 617-638-4803
| | - Zoe R. Gravitz
- Boston University School of Medicine, L-815, 72 E. Newton St., Boston, MA 02118; ; telephone 617-638-4803
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Maksimovskiy AL, McGlinchey RE, Fortier CB, Salat DH, Milberg WP, Oscar-Berman M. White Matter and Cognitive Changes in Veterans Diagnosed with Alcoholism and PTSD. ACTA ACUST UNITED AC 2013; 2:144. [PMID: 24855633 DOI: 10.4172/2329-6488.1000144] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Alcoholism frequently occurs in returning U.S. Veterans, and is often comorbid with Post Traumatic Stress Disorder (PTSD). The goal of this study was to investigate the relationship between white matter changes and neuropsychological alterations in Operation Enduring Freedom, and/or Operation Iraqi Freedom (OEF/OIF) alcoholic Veterans with two primary aims: (1) to examine the relationship of alcoholism to brain structure and function while controlling for the potential effects of comorbid PTSD, and (2) to examine whether the effects of alcoholism are moderated by the quantity of lifetime alcohol consumption. Our sample consisted of 71 deployed OEF/OIF Veterans stratified into four groups: alcoholics without PTSD, alcoholics with PTSD, participants with PTSD without comorbid alcoholism, and control participants without alcoholism or PTSD. Participants were given an extensive neuropsychological and psychiatric assessment battery, as well as Magnetic Resonance Diffusion Tensor Imaging (DT-MRI) scans. Results showed that disruption of executive functioning, and abnormal fractional anisotropy (FA; a measure of axonal integrity) within the frontal subcortical and dorsolateral frontal-parietal regions, occurred independently of the effects of PTSD. Furthermore, these cognitive and neuronal alterations were unique to the most severe subgroup of alcoholics who consumed the greatest amount of alcohol over the course of their lifetime, as compared to the rest of the sample. Axonal integrity within this subgroup, in regions underlying the frontal subcortical area, was shown to be decreased independently of cognitive changes. Integrity of axons underlying the dorsolateral frontal-parietal region, however, was increased. We hypothesized that this is a compensatory mechanism for executive dysfunction.
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Affiliation(s)
- Arkadiy L Maksimovskiy
- Geriatric Research Education and Clinical Center (GRECC) and the Translational Research Center for TBI and Stress-Related Disorders (TRACTS), VA Boston Healthcare System Boston, MA, USA
| | | | | | - David H Salat
- Behavioral Neuroscience Ph.D. Program and Departments of Psychiatry, Neurology, and Anatomy & Neurobiology, Boston University School of Medicine, and VA Boston Healthcare System, Boston, MA, USA
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Pfefferbaum A, Rosenbloom MJ, Fama R, Sassoon SA, Sullivan EV. Transcallosal white matter degradation detected with quantitative fiber tracking in alcoholic men and women: selective relations to dissociable functions. Alcohol Clin Exp Res 2010; 34:1201-11. [PMID: 20477772 PMCID: PMC2910526 DOI: 10.1111/j.1530-0277.2010.01197.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Excessive alcohol consumption can adversely affect white matter fibers and disrupt transmission of neuronal signals. Here, we examined six anatomically defined transcallosal white matter fiber bundles and asked whether any bundle was specifically vulnerable to alcohol, what aspect of white matter integrity was most affected, whether women were more vulnerable than men, and whether evidence of compromise in specific bundles was associated with deficits in balance, sustained attention, associative learning, and psychomotor function, commonly affected in alcoholics. METHODS Diffusion tensor imaging quantitative fiber tracking assessed integrity of six transcallosal white matter bundles in 87 alcoholics (59 men, 28 women) and 88 healthy controls (42 men, 46 women). Measures included orientational diffusion coherence (fractional anisotropy, FA) and magnitude of diffusion, quantified separately for axial (longitudinal; lambdaL) and radial (transverse; lambdaT) diffusivity. The Digit Symbol Test and a test of ataxia were also administered. RESULTS Alcoholism negatively affected callosal FA and lambdaT of all but the sensory-motor bundle. Women showed no evidence for greater vulnerability to alcohol than men. Multiple regression analyses confirmed a double dissociation: higher diffusivity in sensory-motor and parietal bundles was associated with poorer balance but not psychomotor speed, whereas higher diffusivity in prefrontal and temporal bundles was associated with slower psychomotor speed but not balance. CONCLUSIONS This study revealed stronger alcohol effects for FA and radial diffusivity than axial diffusivity, suggesting myelin degradation, but no evidence for greater vulnerability to alcohol in women than men. The presence of brain-behavior relationships provides support for the role of alcoholism-related commissural white matter degradation as a substrate of cognitive and motor impairment. Identification of a double dissociation provides further support for the role of selective white matter integrity in specific domains of performance.
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