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1.
Addict Biol ; 26(2): e12914, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32428984

RESUMEN

Exogenous causes, such as alcohol use, and endogenous factors, such as temperament and sex, can modulate developmental trajectories of adolescent neurofunctional maturation. We examined how these factors affect sexual dimorphism in brain functional networks in youth drinking below diagnostic threshold for alcohol use disorder (AUD). Based on the 3-year, annually acquired, longitudinal resting-state functional magnetic resonance imaging (MRI) data of 526 adolescents (12-21 years at baseline) from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) cohort, developmental trajectories of 23 intrinsic functional networks (IFNs) were analyzed for (1) sexual dimorphism in 259 participants who were no-to-low drinkers throughout this period; (2) sex-alcohol interactions in two age- and sex-matched NCANDA subgroups (N = 76 each), half no-to-low, and half moderate-to-heavy drinkers; and (3) moderating effects of gender-specific alcohol dose effects and a multifactorial impulsivity measure on IFN connectivity in all NCANDA participants. Results showed that sex differences in no-to-low drinkers diminished with age in the inferior-occipital network, yet girls had weaker within-network connectivity than boys in six other networks. Effects of adolescent alcohol use were more pronounced in girls than boys in three IFNs. In particular, girls showed greater within-network connectivity in two motor networks with more alcohol consumption, and these effects were mediated by sensation-seeking only in girls. Our results implied that drinking might attenuate the naturally diminishing sexual differences by disrupting the maturation of network efficiency more severely in girls. The sex-alcohol-dose effect might explain why women are at higher risk of alcohol-related health and psychosocial consequences than men.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Conducta Impulsiva/efectos de los fármacos , Trastornos del Neurodesarrollo/inducido químicamente , Adolescente , Envejecimiento/fisiología , Niño , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Trastornos del Neurodesarrollo/diagnóstico por imagen , Gravedad del Paciente , Caracteres Sexuales , Consumo de Alcohol en Menores , Adulto Joven
2.
Hum Brain Mapp ; 40(8): 2511-2528, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30806009

RESUMEN

Increasing numbers of neuroimaging studies are acquiring data to examine changes in brain architecture by investigating intrinsic functional networks (IFN) from longitudinal resting-state functional MRI (rs-fMRI). At the subject level, these IFNs are determined by cross-sectional procedures, which neglect intra-subject dependencies and result in suboptimal estimates of the networks. Here, a novel longitudinal approach simultaneously extracts subject-specific IFNs across multiple visits by explicitly modeling functional brain development as an essential context for seeking change. On data generated by an innovative simulation based on real rs-fMRI, the method was more accurate in estimating subject-specific IFNs than cross-sectional approaches. Furthermore, only group-analysis based on longitudinally consistent estimates identified significant developmental effects within IFNs of 246 adolescents from the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) study. The findings were confirmed by the cross-sectional estimates when the corresponding group analysis was confined to the developmental effects. Those effects also converged with current concepts of neurodevelopment.


Asunto(s)
Desarrollo del Adolescente/fisiología , Encéfalo/fisiología , Conectoma/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Red Nerviosa/fisiología , Adolescente , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Conectoma/normas , Estudios Transversales , Humanos , Procesamiento de Imagen Asistido por Computador/normas , Estudios Longitudinales , Imagen por Resonancia Magnética , Red Nerviosa/diagnóstico por imagen
3.
Cereb Cortex ; 28(3): 1049-1063, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28168274

RESUMEN

The transition from adolescent to adult cognition and emotional control requires neurodevelopmental maturation likely involving intrinsic functional networks (IFNs). Normal neurodevelopment may be vulnerable to disruption from environmental insult such as alcohol consumption commonly initiated during adolescence. To test potential disruption to IFN maturation, we used resting-state functional magnetic resonance imaging (rs-fMRI) in 581 no-to-low alcohol-consuming and 117 moderate-to-high-drinking youth. Functional seed-to-voxel connectivity analysis assessed age, sex, and moderate alcohol drinking on default-mode, executive-control, salience, reward, and emotion networks and tested cognitive and motor coordination correlates of network connectivity. Among no-to-low alcohol-consuming adolescents, executive-control frontolimbicstriatal connectivity was stronger in older than younger adolescents, particularly boys, and predicted better ability in balance, memory, and impulse control. Connectivity patterns in moderate-to-high-drinking youth were tested mainly in late adolescence when drinking was initiated. Implicated was the emotion network with attenuated connectivity to default-mode network regions. Our cross-sectional rs-fMRI findings from this large cohort of adolescents show sexual dimorphism in connectivity and suggest neurodevelopmental rewiring toward stronger and spatially more distributed executive-control networking in older than younger adolescents. Functional network rewiring in moderate-to-high-drinking adolescents may impede maturation of affective and self-reflection systems and obscure maturation of complex social and emotional behaviors.


Asunto(s)
Envejecimiento/fisiología , Consumo de Bebidas Alcohólicas/fisiopatología , Encéfalo/fisiopatología , Función Ejecutiva/fisiología , Caracteres Sexuales , Adolescente , Encéfalo/diagnóstico por imagen , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Modelos Neurológicos , Pruebas Neuropsicológicas , Oxígeno/sangre , Adulto Joven
4.
Addict Biol ; 23(2): 824-835, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28699704

RESUMEN

Chronic alcoholism is associated with widespread regional differences from controls in brain activity and connectivity dynamics measured by blood-oxygen-level-dependent (BOLD) signals. Identification of alcoholism-related neurofunctional power dynamics using functional magnetic resonance imaging (fMRI) that relate to cognition and behavior may serve as biomarkers of alcoholism. Previously, resting-state fMRI studies examined BOLD signals at a single low-frequency (LF) bandwidth. BOLD signals, however, oscillate systematically at different frequencies and are organized in a resting brain where LF oscillation facilitates long-distance communication between regions across cortical regions, whereas high-frequency (HF) oscillation occurs in closely localized, subcortical areas. Using a frequency power quantification approach, we investigated whether the organization of BOLD signal oscillations across all measured frequency bandwidths is altered in alcoholism and relates to cognitive performance. Frequency-dependent oscillation power differences between 56 sober alcoholics and 56 healthy controls occurred for all frequency bands. Alcoholics exhibited greater frequency oscillation power in the orbitofrontal cortex and less power in the posterior insula within the HF bandwidth than controls. Aberrant orbitofrontal HF power was associated with poorer memory performance and slower psychomotor speed in alcoholics. Middle-frequency and LF power proved sensitive in detecting altered frequency oscillation dynamics in parietal and postcentral cortical regions of alcoholics. This study is novel in identifying alcohol-related differences in BOLD oscillation power of the full fMRI frequency bandwidth. Specifically, HF power aberrations were associated with poorer cognitive functioning in alcoholism and may serve as a biomarker for identifying neural targets for repair.


Asunto(s)
Alcoholismo/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Adulto , Alcoholismo/fisiopatología , Alcoholismo/psicología , Estudios de Casos y Controles , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiopatología , Cognición/fisiología , Femenino , Neuroimagen Funcional/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiopatología
5.
Cereb Cortex ; 25(11): 4155-68, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24935777

RESUMEN

Chronic alcohol consumption affects multiple cognitive processes supported by far-reaching cerebral networks. To identify neurofunctional mechanisms underlying selective deficits, 27 sober alcoholics and 26 age-matched controls underwent resting-state functional magnetic resonance imaging and neuropsychological testing. Functional connectivity analysis assessed the default mode network (DMN); integrative executive control (EC), salience (SA), and attention (AT) networks; primary somatosensory, auditory, and visual (VI) input networks; and subcortical reward (RW) and emotion (EM) networks. The groups showed an extensive overlap of intrinsic connectivity in all brain networks examined, suggesting overall integrity of large-scale functional networks. Despite these similar patterns, connectivity analyses identified network-specific differences of weaker within-network connectivity and expanded connectivity to regions outside the main networks in alcoholics compared with controls. For AT and VI networks, better task performance was related to expanded connectivity in alcoholism, supporting the concept of network expansion as a neural mechanism for functional compensation. For default mode, SA, RW, and EC networks, both weaker within-network and expanded outside-network connectivity correlated with poorer performance and mood. Current smoking contributed to some of these abnormalities in connectivity. The observed pattern of resting-state connectivity might reflect neural vulnerability of intrinsic networking in alcoholics and suggests a mechanism to explain signature impairments in EM, RW evaluation, and EC ability.


Asunto(s)
Alcoholismo/patología , Mapeo Encefálico , Encéfalo/fisiopatología , Vías Nerviosas/fisiopatología , Descanso , Encéfalo/irrigación sanguínea , Estudios de Casos y Controles , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/irrigación sanguínea , Oxígeno/sangre , Estadísticas no Paramétricas
6.
Cereb Cortex ; 24(5): 1397-408, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23355606

RESUMEN

Personal attitude toward ambiguity contributes to individual differences in decision making in uncertain situations. Operationally, these attitudes reflect the various coping strategies elected to overcome the limited information. A key brain region involved in cognitive control for performance adjustments is the dorsal anterior cingulate cortex (dACC). To test how dACC functional network connectivity would be modulated by uncertainty and differ between individuals, 24 healthy participants underwent functional MRI in 3 sequential runs: 1 resting-state and 2 decision-making task runs. Individuals with lower nonplanning impulsiveness made greater use of a Pass option and avoided uncertain ambiguous situations. Seed-based functional connectivity analysis during the task runs revealed that stronger activation synchrony between the left dACC and the right anterior insula correlated with greater use of a Pass response option. During the resting-state, stronger resting-state functional connectivity between the left dACC and the ventral striatum predicted the adoption of Pass as a behavioral strategy and correlated with stronger task-activated synchrony between the dACC and the right anterior insula. Our findings indicate that that the synchrony between the dACC and insula-striatal circuitry was greater in individuals with low compared with high nonplanning impulsiveness and contributed to adopting Pass as a useful behavioral strategy.


Asunto(s)
Cuerpo Estriado/fisiopatología , Toma de Decisiones , Trastornos Disruptivos, del Control de Impulso y de la Conducta/diagnóstico , Giro del Cíngulo/fisiopatología , Incertidumbre , Adulto , Mapeo Encefálico , Distribución de Chi-Cuadrado , Cuerpo Estriado/irrigación sanguínea , Femenino , Giro del Cíngulo/irrigación sanguínea , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/irrigación sanguínea , Oxígeno/sangre , Reconocimiento Visual de Modelos , Estimulación Luminosa , Valor Predictivo de las Pruebas , Tiempo de Reacción
7.
Cereb Cortex ; 23(1): 97-104, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22275479

RESUMEN

Abnormal brain activity may reflect compensation when observed in patients who perform normally on tests requiring functions usually observed as impaired. Operational criteria defining compensation have been described and aid in distinguishing compensatory from chance events. Here, we tested whether previously published functional magnetic resonance imaging data acquired in 15 recovering alcoholics and 15 controls at rest and while performing a spatial working memory task would fulfill criteria defining functional compensation. Multivariate analysis tested how well abnormal activation in the affected group predicted normal performance, despite low or no activation in brain regions invoked by controls to accomplish the same task. By identifying networks that uniquely and positively correlated with good performance, we provide evidence for compensatory recruitment of cerebellar-based functional networks by alcoholics. Whereas controls recruited prefrontal-cerebellar regions VI/Crus I known to subserve working memory, alcoholics recruited 2 other parallel frontocerebellar loops: dorsolateral prefrontal cortex (DLPFC)-cerebellar VIII system during rest and DLPFC-cerebellar VI system while task engaged. Greater synchronous activity between cerebellar lobule VIII and DLPFC at rest and greater activation within cerebellar lobule VI and DLPFC during task predicted better working memory performance. Thus, higher intrinsic cerebellar activity in alcoholics was an adequate condition for triggering task-relevant activity in the frontal cortex required for normal working memory performance.


Asunto(s)
Alcoholismo/fisiopatología , Alcoholismo/rehabilitación , Encéfalo/fisiopatología , Trastornos de la Memoria/fisiopatología , Trastornos de la Memoria/rehabilitación , Plasticidad Neuronal , Adaptación Fisiológica , Adulto , Alcoholismo/complicaciones , Mapeo Encefálico , Femenino , Humanos , Masculino , Trastornos de la Memoria/etiología , Recuperación de la Función/fisiología
8.
Dev Cogn Neurosci ; 69: 101448, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39307082

RESUMEN

PURPOSE: Alcohol-related blackouts (ARBs) are common in adolescents and emerging adults. ARBs may also be indicative of persistent, alcohol-related neurocognitive changes. This study explored ARBs as a predictor of altered structural brain development and associated cognitive correlates. METHODS: Longitudinal growth curve modeling estimated trajectories of brain volume across 6 years in participants from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study (n = 800, 213 with lifetime ARB history). While controlling for demographics and overall alcohol use, ARB history was analyzed as a predictor of brain volume growth in regions associated with alcohol-related cognitive change. Post hoc analyses examined whether ARBs moderated relationships between brain morphology and cognition. RESULTS: ARBs significantly predicted attenuated development of fusiform gyrus and hippocampal volume at unique timepoints compared to overall alcohol use. Alcohol use without ARBs significantly predicted attenuated fusiform and hippocampal growth at earlier and later timepoints, respectively. Despite altered development in regions associated with memory, ARBs did not significantly moderate relationships between brain volume and cognitive performance. CONCLUSION: ARBs and overall alcohol use predicted altered brain development in the fusiform gyrus and hippocampus at different timepoints, suggesting ARBs represent a unique marker of neurocognitive risk in younger drinkers.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Humanos , Masculino , Femenino , Estudios Longitudinales , Adolescente , Encéfalo/crecimiento & desarrollo , Encéfalo/efectos de los fármacos , Adulto Joven , Consumo de Bebidas Alcohólicas/efectos adversos , Hipocampo/crecimiento & desarrollo , Hipocampo/efectos de los fármacos , Adulto , Cognición/efectos de los fármacos , Lóbulo Temporal/crecimiento & desarrollo , Lóbulo Temporal/efectos de los fármacos
9.
J Affect Disord ; 346: 234-241, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-37944709

RESUMEN

PURPOSE: The first year of the COVID-19 pandemic constituted a major life stress event for many adolescents, associated with disrupted school, behaviors, social networks, and health concerns. However, pandemic-related stress was not equivalent for everyone and could have been influenced by pre-pandemic factors including brain structure and sleep, which both undergo substantial development during adolescence. Here, we analyzed clusters of perceived stress levels across the pandemic and determined developmentally relevant pre-pandemic risk factors in brain structure and sleep of persistently high stress during the first year of the COVID-19 pandemic. METHODS: We investigated longitudinal changes in perceived stress at six timepoints across the first year of the pandemic (May 2020-March 2021) in 5559 adolescents (50 % female; age range: 11-14 years) in the United States (U.S.) participating in the Adolescent Brain Cognitive Development (ABCD) study. In 3141 of these adolescents, we fitted machine learning models to identify the most important pre-pandemic predictors from structural MRI brain measures and self-reported sleep data that were associated with persistently high stress across the first year of the pandemic. RESULTS: Patterns of perceived stress levels varied across the pandemic, with 5 % reporting persistently high stress. Our classifiers accurately detected persistently high stress (AUC > 0.7). Pre-pandemic brain structure, specifically cortical volume in temporal regions, and cortical thickness in multiple parietal and occipital regions, predicted persistent stress. Pre-pandemic sleep difficulties and short sleep duration were also strong predictors of persistent stress, along with more advanced pubertal stage. CONCLUSIONS: Adolescents showed variable stress responses during the first year of the COVID-19 pandemic, and some reported persistently high stress across the whole first year. Vulnerability to persistent stress was evident in several brain structural and self-reported sleep measures, collected before the pandemic, suggesting the relevance of other pre-existing individual factors beyond pandemic-related factors, for persistently high stress responses.


Asunto(s)
COVID-19 , Humanos , Adolescente , Femenino , Niño , Masculino , Pandemias , Sueño , Duración del Sueño , Lóbulo Occipital
10.
Brain Res Bull ; : 111085, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39343322

RESUMEN

The thalamus, with its reciprocal connections to and from cortical, subcortical, and cerebellar regions, is a central active participant in multiple functional brain networks. Structural MRI studies measuring the entire thalamus without respect to its regional or nuclear divisions report volume shrinkage in diseases including HIV infection, alcohol use disorder (AUD), and their comorbidity (HIV+AUD). Here, we examined relations between thalamic subregions (anterior, ventral, medial, and posterior) and neuropsychological functions (attention/working memory, executive functioning, episodic memory, and motor skills). Volumes of thalamic subregions were derived from automatic segmentations of standard T1 weighted MRIs of 65 individuals with HIV, 189 with AUD, 80 with HIV+AUD comorbidity, and 141 healthy controls (CTRL). Total thalamic volume was smaller and cognitive and motor composite scores were lower in the three diagnostic groups relative to the CTRL group. The AUD and HIV+AUD groups had significantly smaller thalamic subregional volumes than the CTRL group. The HIV+AUD group had smaller anterior thalamic volume than the HIV-only group and smaller ventral thalamic volume than the AUD-only group. In the HIV+AUD group, memory scores correlated with anterior thalamic volumes, attention/working memory scores correlated with posterior and medial thalamic volumes, and motor skill scores correlated with posterior thalamic volumes. Exploratory analyses focused on the HIV+AUD group indicated that within the posterior thalamic region, the pulvinar and medial geniculate nuclei were related to attention/working memory scores, and the pulvinar was related to motor skills scores. This study is novel in locating volume deficits in specific thalamic subregions, in addition to the thalamus as a whole, in HIV, AUD, and their comorbidity and in identifying functional ramifications of these deficits. Taken together, this study highlights the relevance of thalamic subregional volume deficits to dissociable cognitive and motor processes.

11.
bioRxiv ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39229241

RESUMEN

Background and Purpose: An association recently emerged between magnetic resonance imaging (MRI)-visible perivascular spaces (MV-PVS) with intracerebral solute clearance and neuroinflammation, in adults. However, it is unknown how MV-PVS change throughout adolescence and what factors influence MV-PVS volume and morphology. This study assesses the temporal evolution of MV-PVS volume in adolescents and young adults, and secondarily evaluates the relationship between MV-PVS, age, sex, and body mass index (BMI). Materials and Methods: This analysis included a 783 participant cohort from the longitudinal multicenter National Consortium on Alcohol and Neurodevelopment in Adolescence study that involved up to 6 imaging visits spanning 5 years. Healthy adolescents aged 12-21 years at study entry with at least two MRI scans were included. The primary outcome was mean MV-PVS volume (mm 3 /white matter cm 3 ). Results: On average, males had greater MV-PVS volume at all ages compared to females. A linear mixed-effect model for MV-PVS volume was performed. Mean BMI and increases in a person's BMI were associated with increases in MV-PVS volume over time. In females only, changes in BMI correlated with MV-PVS volume. One unit increase in BMI above a person's average BMI was associated with a 0.021 mm 3 /cm 3 increase in MV-PVS volume (p<0.001). Conclusion: This longitudinal study showed sex differences in MV-PVS features during adolescence and young adulthood. Importantly, we report that increases in BMI from a person's mean BMI are associated with increases in MV-PVS volume in females only. These findings suggest a potential link between MV-PVS, sex, and BMI that warrants future study.

12.
Neuroimage ; 77: 195-206, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23567886

RESUMEN

We present a novel approach - DTI-based fiber tract-driven topographical mapping (FTTM) - to map and measure the influence of age on the integrity of interhemispheric fibers and challenge their selective functions with measures of interhemispheric integration of lateralized information. This approach enabled identification of spatially specific topographical maps of scalar diffusion measures and their relation to measures of visuomotor performance. Relative to younger adults, older adults showed lower fiber integrity indices in anterior than posterior callosal fibers. FTTM analysis identified a dissociation in the microstructural-function associates between age groups: in younger adults, genu fiber integrity correlated with interhemispheric transfer time, whereas in older adults, body fiber integrity was correlated with interhemispheric transfer time with topographical specificity along left-lateralized callosal fiber trajectories. Neural co-activation from redundant targets was evidenced by fMRI-derived bilateral extrastriate cortex activation in both groups, and a group difference emerged for a pontine activation cluster that was differently modulated by response hand in older than younger adults. Bilateral processing advantages in older but not younger adults further correlated with fiber integrity in transverse pontine fibers that branch into the right cerebellar cortex, thereby supporting a role for the pons in interhemispheric facilitation. In conclusion, in the face of compromised anterior callosal fibers, older adults appear to use alternative pathways to accomplish visuomotor interhemispheric information transfer and integration for lateralized processing. This shift from youthful associations may indicate recruitment of compensatory mechanisms involving medial corpus callosum fibers and subcortical pathways.


Asunto(s)
Envejecimiento/patología , Mapeo Encefálico/métodos , Encéfalo/patología , Lateralidad Funcional/fisiología , Vías Nerviosas/patología , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Encéfalo/fisiología , Imagen de Difusión Tensora , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiología , Adulto Joven
13.
Phys Med Biol ; 68(5)2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36638532

RESUMEN

Objective.To document the bias of thesimplifiedfree water model of diffusion MRI (dMRI) signal vis-à-vis aspecificmodel which, in addition to diffusion, incorporates compartment-specific proton density (PD), T1 recovery during repetition time (TR), and T2 decay during echo time (TE).Approach.Both models assume that volume fractionfof the total signal in any voxel arises from the free water compartment (fw) such as cerebrospinal fluid or edema, and the remainder (1-f) from hindered water (hw) which is constrained by cellular structures such as white matter (WM). Thespecificandsimplifiedmodels are compared on a synthetic dataset, using a range of PD, T1 and T2 values. We then fit the models to anin vivohealthy brain dMRI dataset. For bothsyntheticandin vivodata we use experimentally feasible TR, TE, signal-to-noise ratio (SNR) and physiologically plausible diffusion profiles.Main results.From the simulations we see that the difference between the estimatedsimplified fandspecific fis largest for mid-range ground-truthf, and it increases as SNR increases. The estimation of volume fractionfis sensitive to the choice of model,simplifiedorspecific, but the estimated diffusion parameters are robust to small perturbations in the simulation.Specific fis more accurate and precise thansimplified f. In the white matter (WM) regions of thein vivoimages,specific fis lower thansimplified f.Significance.In dMRI models for free water, accounting for compartment specific PD, T1 and T2, in addition to diffusion, improves the estimation of model parameters. This extra model specification attenuates the estimation bias of compartmental volume fraction without affecting the estimation of other diffusion parameters.


Asunto(s)
Protones , Sustancia Blanca , Algoritmos , Imagen de Difusión por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Agua/química , Procesamiento de Imagen Asistido por Computador/métodos
14.
J Psychiatr Res ; 163: 230-239, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37230007

RESUMEN

Experience of childhood trauma, especially physical, emotional, and sexual abuse, carries a risk for developing alcohol use disorder (AUD) and engaging in risky behaviors that can result in HIV infection. AUD and HIV are associated with compromised self-reported health-related quality of life (HRQoL) possibly intersecting with childhood trauma. To determine whether poor HRQoL is heightened by AUD, HIV, their comorbidity (AUD + HIV), number of trauma events, or poor resilience, 108 AUD, 45 HIV, 52 AUD + HIV, and 67 controls completed the SF-21 HRQoL, Brief Resilience Scale (BRS), Ego Resiliency Scale (ER-89), and an interview about childhood trauma. Of the 272 participants, 116 reported a trauma history before age 18. Participants had a blood draw, AUDIT questionnaire, and interview about lifetime alcohol consumption. AUD, HIV, and AUD + HIV had lower scores on HRQoL and resilience composite comprising the BRS and ER-89 than controls. Greater resilience was a significant predictor of better quality of life in all groups. HRQoL was differentially moderated in AUD and HIV: more childhood traumas predicted poorer quality of life in AUD and controls, whereas higher T-lymphocyte count contributed to better quality of life in HIV. This study is novel in revealing a detrimental impact on HRQoL from AUD, HIV, and their comorbidity, with differential negative contribution from trauma and beneficial effect of resilience to quality of life. Channeling positive effects of resilience and reducing the incidence and negative impact of childhood trauma may have beneficial effects on health-related quality of life in adulthood independent of diagnosis.


Asunto(s)
Experiencias Adversas de la Infancia , Alcoholismo , Infecciones por VIH , Humanos , Adolescente , Alcoholismo/epidemiología , Alcoholismo/psicología , Infecciones por VIH/epidemiología , Calidad de Vida/psicología , Consumo de Bebidas Alcohólicas
15.
Brain Struct Funct ; 228(3-4): 845-858, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37069296

RESUMEN

Episodic memory deficits occur in people living with HIV (PLWH) and individuals with Parkinson's disease (PD). Given known effects of HIV and PD on frontolimbic systems, episodic memory deficits are often attributed to executive dysfunction. Although executive dysfunction, evidenced as retrieval deficits, is relevant to mnemonic deficits, learning deficits may also contribute. Here, the California Verbal Learning Test-II, administered to 42 PLWH, 41 PD participants, and 37 controls, assessed learning and retrieval using measures of free recall, cued recall, and recognition. Executive function was assessed with a composite score comprising Stroop Color-Word Reading and Backward Digit Spans. Neurostructural correlates were examined with MRI of frontal (precentral, superior, orbital, middle, inferior, supplemental motor, medial) and limbic (hippocampus, thalamus) volumes. HIV and PD groups were impaired relative to controls on learning and free and cued recall trials but did not differ on recognition or retention of learned material. In no case did executive functioning solely account for the observed mnemonic deficits or brain-performance relations. Critically, the shared learning and retrieval deficits in HIV and PD were related to different substrates of frontolimbic mnemonic neurocircuitry. Specifically, diminished learning and poorer free and cued recall were related to smaller orbitofrontal volume in PLWH but not PD, whereas diminished learning in PD but not PLWH was related to smaller frontal superior volume. In PD, poorer recognition correlated with smaller thalamic volume and poorer retention to hippocampal volume. Although memory deficits were similar, the neural correlates in HIV and PD suggest different pathogenic mechanisms.


Asunto(s)
Infecciones por VIH , Memoria Episódica , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/patología , Infecciones por VIH/complicaciones , Trastornos de la Memoria/diagnóstico por imagen , Trastornos de la Memoria/etiología , Recuerdo Mental , Pruebas Neuropsicológicas
16.
Alcohol Clin Exp Res ; 36(12): 2017-27, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22577873

RESUMEN

BACKGROUND: Multimodal imaging combining 2 or more techniques is becoming increasingly important because no single imaging approach has the capacity to elucidate all clinically relevant characteristics of a network. METHODS: This review highlights recent advances in multimodal neuroimaging (i.e., combined use and interpretation of data collected through magnetic resonance imaging [MRI], functional MRI, diffusion tensor imaging, positron emission tomography, magnetoencephalography, MR perfusion, and MR spectroscopy methods) that leads to a more comprehensive understanding of how acute and chronic alcohol consumption affect neural networks underlying cognition, emotion, reward processing, and drinking behavior. RESULTS: Several innovative investigators have started utilizing multiple imaging approaches within the same individual to better understand how alcohol influences brain systems, both during intoxication and after years of chronic heavy use. CONCLUSIONS: Their findings can help identify mechanism-based therapeutic and pharmacological treatment options, and they may increase the efficacy and cost effectiveness of such treatments by predicting those at greatest risk for relapse.


Asunto(s)
Alcoholismo/complicaciones , Encéfalo/efectos de los fármacos , Etanol/efectos adversos , Neuroimagen , Encéfalo/patología , Imagen de Difusión Tensora , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Magnetoencefalografía , Tomografía de Emisión de Positrones
17.
Drug Alcohol Depend ; 235: 109435, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35395501

RESUMEN

BACKGROUND: A neural substrate of alcohol-related instability of gait and balance is the cerebellum. Whether disruption of neural communication between cerebellar and cortical brain regions exerts an influence on ataxia in alcohol use disorder (AUD) was the focus of this study. METHODS: Study groups comprised 32 abstinent AUD participants and 22 age- and sex-matched healthy controls (CTL). All participants underwent clinical screening, motor testing, and resting-state functional MR imaging analyzed for functional connectivity (FC) among 90 regions across the whole cerebrum and cerebellum. Ataxia testing quantified gait and balance with the Fregly-Graybiel Ataxia Battery conducted with and without vision. RESULTS: The AUD group achieved lower scores than the CTL group on balance performance, which was disproportionately worse for eyes open than eyes closed in the AUD relative to the CTL group. Differences in ataxia were accompanied by differences in FC marked by cerebellar-frontal and cerebellar-parietal hyperconnectivity and cortico-cortical hypoconnectivity in the AUD relative to the control group. Lifetime alcohol consumption correlated significantly with AUD-related FC aberrations, which explained upwards of 69% of the AUD ataxia score variance. CONCLUSION: Heavy, chronic alcohol consumption is associated with disorganized neural communication among cerebellar-cortical regions and contributes to ataxia in AUD. Ataxia, which is known to accelerate with age and be exacerbated with AUD, can threaten functional independence. Longitudinal studies are warranted to address whether extended sobriety quells ataxia and normalizes aberrant FC contributing to instability.


Asunto(s)
Alcoholismo , Consumo de Bebidas Alcohólicas , Ataxia , Encéfalo , Cerebelo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Vías Nerviosas
18.
Brain Imaging Behav ; 16(4): 1776-1793, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35294979

RESUMEN

Expression of executive dysfunctions is marked by substantial heterogeneity in people living with HIV infection (PLWH) and attributed to neuropathological degradation of frontostriatal circuitry with age and disease. We compared the neurophysiology of executive function in older PLWH and Parkinson's disease (PD), both affecting frontostriatal systems. Thirty-one older PLWH, 35 individuals with PD, and 28 older healthy controls underwent executive task-activated fMRI, neuropsychological testing, and a clinical motor exam. fMRI task conditions distinguished cognitive control operations, invoking a lateral frontoparietal network, and motor control operations, activating a cerebellar-precentral-medial prefrontal network. HIV-specific findings denoted a prominent sensorimotor hypoactivation during cognitive control and striatal hypoactivation during motor control related to CD4+ T cell count and HIV disease duration. Activation deficits overlapped for PLWH and PD, relative to controls, in dorsolateral frontal, medial frontal, and middle cingulate cortices for cognitive control, and in limbic, frontal, parietal, and cerebellar regions for motor control. Thus, despite well-controlled HIV infection, frontostriatal and sensorimotor activation deficits occurred during executive control in older PLWH. Overlapping activation deficits in posterior cingulate and hippocampal regions point toward similarities in mesocorticolimbic system aberrations among older PLWH and PD. The extent of pathophysiology in PLWH was associated with variations in immune system health, neural signature consistent with subclinical parkinsonism, and mild neurocognitive impairment. The failure to adequately engage these pathways could be an early sign for cognitive and motor functional decline in the aging population of PLWH.


Asunto(s)
Infecciones por VIH , Enfermedad de Parkinson , Anciano , Función Ejecutiva/fisiología , Infecciones por VIH/complicaciones , Infecciones por VIH/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Pruebas Neuropsicológicas
19.
J Affect Disord ; 312: 30-38, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35688394

RESUMEN

BACKGROUND: Given the high prevalence of depressive symptoms reported by adolescents and associated risk of experiencing psychiatric disorders as adults, differentiating the trajectories of the symptoms related to negative valence at an individual level could be crucial in gaining a better understanding of their effects later in life. METHODS: A longitudinal deep learning framework is presented, identifying self-reported and behavioral measurements that detect the depressive symptoms associated with the Negative Valence System domain of the NIMH Research Domain Criteria (RDoC). RESULTS: Applied to the annual records of 621 participants (age range: 12 to 17 years) of the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA), the deep learning framework identifies predictors of negative valence symptoms, which include lower extraversion, poorer sleep quality, impaired executive control function and factors related to substance use. LIMITATIONS: The results rely mainly on self-reported measures and do not provide information about the underlying neural correlates. Also, a larger sample is required to understand the role of sex and other demographics related to the risk of experiencing symptoms of negative valence. CONCLUSIONS: These results provide new information about predictors of negative valence symptoms in individuals during adolescence that could be critical in understanding the development of depression and identifying targets for intervention. Importantly, findings can inform preventive and treatment approaches for depression in adolescents, focusing on a unique predictor set of modifiable modulators to include factors such as sleep hygiene training, cognitive-emotional therapy enhancing coping and controllability experience and/or substance use interventions.


Asunto(s)
Terapia Cognitivo-Conductual , Trastornos Mentales , Adaptación Psicológica , Adolescente , Adulto , Niño , Terapia Cognitivo-Conductual/métodos , Emociones , Humanos , Autoinforme
20.
Artículo en Inglés | MEDLINE | ID: mdl-33558196

RESUMEN

BACKGROUND: Individuals with alcohol use disorder (AUD) have a heightened risk of contracting HIV infection. The effects of these two diseases and their comorbidity on brain structure have been well described, but their effects on brain function have never been investigated at the scale of whole-brain connectomes. METHODS: In contrast with prior studies that restricted analyses to specific brain networks or examined relatively small groups of participants, our analyses are based on whole-brain functional connectomes of 292 participants. RESULTS: Relative to participants without AUD, the functional connectivity between the anterior cingulate cortex and orbitofrontal cortex was lower for participants with AUD. Compared with participants without AUD+HIV comorbidity, the functional connectivity between the anterior cingulate cortex and hippocampus was lower for the AUD+HIV participants. Compromised connectivity between these pairs was significantly correlated with greater total lifetime alcohol consumption; the effects of total lifetime alcohol consumption on executive functioning were significantly mediated by the functional connectivity between the pairs. CONCLUSIONS: Taken together, our results suggest that the functional connectivity of the anterior cingulate cortex is disrupted in individuals with AUD alone and AUD with HIV infection comorbidity. Moreover, the affected connections are associated with deficits in executive functioning, including heightened impulsiveness.


Asunto(s)
Alcoholismo , Infecciones por VIH , Humanos , Alcoholismo/complicaciones , Giro del Cíngulo , Infecciones por VIH/complicaciones , Imagen por Resonancia Magnética/métodos , Consumo de Bebidas Alcohólicas , Comorbilidad
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