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The ability to anticipate and process predictable unpleasant events, while also regulating emotional reactivity, is an adaptive skill. The current article and a companion in this issue test for potential changes in predictable event processing across the childhood-to-adolescence transition, a key developmental period for biological systems that support cognitive/ emotional abilities. While the companion article focuses on neurophysiology of predictable event processing itself, the present article examines peripheral emotional response regulation and attention modulation that coincides with event processing. A total of 315 third-, sixth-, or ninth-grade individuals saw 5-s cues predicting "scary," "every day," or uncertain pictures, and here, blink reflexes and brain event-related potentials (ERPs) elicited by peripheral noise probes are analyzed. During the cue, blink reflexes and probe ERP (P200) amplitudes were increased when the cue predicted scary, compared to everyday, content. After picture onset, reflex enhancement by scary content then disappeared for predictable images, whereas ERP modulation was similar regardless of predictability. Patterns are similar to those in adults and suggest (1) sustained defensive response priming and enhancement of peripheral attention during aversive anticipation, and (2) an ability, even in pre-adolescents, to downregulate defensive priming while maintaining attentional modulation once an awaited predictable aversive event occurs.
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Potenciales Evocados , Reflejo de Sobresalto , Adulto , Humanos , Adolescente , Niño , Reflejo de Sobresalto/fisiología , Estimulación Luminosa , Potenciales Evocados/fisiología , Emociones/fisiología , Atención/fisiología , ElectroencefalografíaRESUMEN
The ability to anticipate and process predictable unpleasant events, while also regulating emotional reactivity, is an adaptive skill. The current article and a companion in this issue test for potential changes in predictable event processing across the childhood-to-adolescence transition, a key developmental period for biological systems that support cognitive/emotional abilities. While the companion article focuses on emotion regulation and peripheral attention modulation in predictable unpleasant contexts, the current paper presents neurophysiological markers of predictable event processing itself. 315 third-, sixth-, or ninth-grade individuals saw 5-s cues predicting "scary," "every day," or uncertain image content; in this paper, cue- and picture-locked event-related potentials (ERPs) are analyzed. During the cue, early ERP positivities were increased and later slow-wave negativities were reduced when predicted content was scary as compared with mundane. After picture onset, a picture processing-related positivity was then increased for scary compared with everyday images regardless of predictability. Cue-interval data suggest enhanced processing of scary cues and reduced anticipatory processing of scary images-opposite to adults. After event onset, meanwhile, emotional ERP enhancement regardless of predictability is similar to adults and suggests that even preadolescent individuals maintain preferential engagement with unpleasant events when they are predictable.
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Electroencefalografía , Potenciales Evocados , Adulto , Humanos , Adolescente , Niño , Potenciales Evocados/fisiología , Emociones/fisiología , Miedo , Atención/fisiología , Señales (Psicología)RESUMEN
Background: The goal of this study was to conduct a preliminary network analysis (using graph-theory measures) of intrinsic functional connectivity in adult smokers, with an exploration of sex differences in smokers. Methods: Twenty-seven adult smokers (13 males; mean age = 35) and 17 sex and age-matched controls (11 males; mean age = 35) completed a blood oxygen level-dependent resting state functional magnetic resonance imaging experiment. Data analysis involved preprocessing, creation of connectivity matrices using partial correlation, and computation of graph-theory measures using the Brain Connectivity Toolbox. Connector hubs and additional graph-theory measures were examined for differences between smokers and controls and correlations with nicotine dependence. Sex differences were examined in a priori regions of interest based on prior literature. Results: Compared to nonsmokers, connector hubs in smokers emerged primarily in limbic (parahippocampus) and salience network (cingulate cortex) regions. In addition, global influence of the right insula and left nucleus accumbens was associated with higher nicotine dependence. These trends were present in male but not female smokers. Conclusions: Network communication was altered in smokers, primarily in limbic and salience network regions. Network topology was associated with nicotine dependence in male but not female smokers in regions associated with reinforcement (nucleus accumbens) and craving (insula), consistent with the idea that male smokers are more sensitive to the reinforcing aspects of nicotine than female smokers. Implications: Identifying alterations in brain network communication in male and female smokers can help tailor future behavioral and pharmacological smoking interventions. Male smokers showed alterations in brain networks associated with the reinforcing effects of nicotine more so than females, suggesting that pharmacotherapies targeting reinforcement and craving may be more efficacious in male smokers.
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Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Red Nerviosa/diagnóstico por imagen , Caracteres Sexuales , Fumar , Tabaquismo/diagnóstico por imagen , Adulto , Encéfalo/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiología , Refuerzo en Psicología , Fumadores/psicología , Fumar/epidemiología , Fumar/psicología , Tabaquismo/epidemiología , Tabaquismo/psicologíaRESUMEN
This study examined the neural basis of processing high- and low-message sensation value (MSV) antidrug public service announcements (PSAs) in high (HSS) and low sensation seekers (LSS) using fMRI. HSS more strongly engaged the salience network when processing PSAs (versus LSS), suggesting that high-MSV PSAs attracted their attention. HSS and LSS participants who engaged higher level cognitive processing regions reported that the PSAs were more convincing and believable and recalled the PSAs better immediately after testing. In contrast, HSS and LSS participants who strongly engaged visual attention regions for viewing PSAs reported lower personal relevance. These findings provide neurobiological evidence that high-MSV content is salient to HSS, a primary target group for antidrug messages, and additional cognitive processing is associated with higher perceived message effectiveness.
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Imagen por Resonancia Magnética , Neurobiología/métodos , Comunicación Persuasiva , Avisos de Utilidad Pública como Asunto , Asunción de Riesgos , Adulto , Femenino , Humanos , Masculino , Recuerdo Mental , Trastornos Relacionados con Sustancias/prevención & control , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Adolescence is a particularly vulnerable period for the onset of substance use disorders and other psychopathology. Individual variability in motivational tendencies and temperament and significant changes in functional brain organization during adolescence are important factors to consider in the development of substance use and dependence. Recent conceptualizations suggest that sensitivity to reward is heightened in adolescence and that this motivation tendency may precipitate subsequent substance abuse. The present study examined the role of personality traits in mesolimbic neurobehavioral response on a monetary incentive delay (MID) task in young adolescents (11-14 years) and emerging adults (18-25 years) using functional magnetic resonance imaging. As a group, adolescents were not more sensitive to gains than losses compared to adults during either anticipatory and feedback phases; instead, compared to adults they showed less sensitivity to incentive magnitude in mesolimbic circuitry during anticipation and feedback stages. However, personality modulated this response such that adolescents high in impulsivity or low in avoidance tendencies showed greater gain sensitivity and adolescents high in avoidance showed greater loss sensitivity during cue anticipation. In adults, mesolimbic response was modulated by the impulsivity construct such that high-impulsive adults showed reduced magnitude sensitivity during both anticipation and feedback compared to low impulsive adults. The present findings suggest that impulsive personality significantly modulates mesolimbic reward response during both adolescence and adulthood but avoidance and approach tendencies also modulate this response in adolescents. Moreover, personality modulated incentive valence in adolescents but incentive magnitude in adults. Collectively, these findings suggest that mesolimbic reward circuitry function is modulated by somewhat different parameters in adolescence than in adulthood.
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Mapeo Encefálico , Encéfalo/fisiología , Conducta Impulsiva/fisiología , Motivación/fisiología , Recompensa , Adolescente , Adulto , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Adulto JovenRESUMEN
Although established adult smokers with long histories of nicotine dependence have lower neural tissue volume than non-smokers, it is not clear if lower regional brain volume is also observed in younger, less established smokers. The primary goal of this study was to investigate neural tissue volume in a large group of smokers and non-smokers, with a secondary goal of measuring the impact of age on these effects. We used voxel-based morphometry to compare regional gray matter volume in 118 individuals (59 smokers, 59 age- and gender-matched non-smokers). Younger smokers had significantly lower gray matter volume in the left thalamus and the left amygdala than their non-smoking peers (family-wise error-corrected clusters, P < 0.05). There was no correlation between smoking use variables and tissue volume among younger smokers. Established smokers had significantly lower gray matter volume than age-matched non-smokers in the insula, parahippocampal gyrus and pallidum. Medial prefrontal cortex gray matter volume was negatively correlated with pack-years of smoking among the established smokers, but not the younger smokers. These data reveal that regional tissue volume differences are not limited exclusively to established smokers. Deficits in young adults indicate that cigarette smoking may either be deleterious to the thalamus and amygdala at an earlier age than previously reported, or that pre-existing differences in these areas may predispose individuals to the development of nicotine dependence.
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Encéfalo/patología , Sustancia Gris/patología , Fumar/patología , Tabaquismo/patología , Adulto , Factores de Edad , Amígdala del Cerebelo/patología , Estudios de Casos y Controles , Corteza Cerebral/patología , Femenino , Globo Pálido/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Giro Parahipocampal/patología , Corteza Prefrontal/patología , Tálamo/patología , Adulto JovenRESUMEN
PURPOSE: Obstructive sleep apnea syndrome (OSAS) has a higher prevalence in postmenopausal women who are not on hormone replacement therapy (HRT), as compared to premenopausal women. Cognitive impairment (CI) is associated with OSAS and the early postmenopausal state. We hypothesized that compared to postmenopausal women at low risk for OSAS, postmenopausal women at high risk for OSAS would report worse cognitive function. METHODS: Early postmenopausal women not on HRT between the ages of 45 and 60 years, within 5 years of natural menopause, were enrolled. Participants completed a REDCap survey which collected information on demographics and risk factors, Berlin questionnaire to screen subjects for OSAS risk, and the Mail-In Cognitive Function Screening Instrument (MCFSI) score which was used to assess CI. RESULTS: Of 381 respondents, 127 were omitted due to missing/duplicate data or not meeting inclusion criteria. One hundred fifty-four women were classified as high risk for OSAS (OSAS+), and 100 were classified as low risk for OSAS (OSAS-). OSAS- women reported lifetime smoking, lifetime drinking, and recreational drug use more often than OSAS+ women, while OSAS+ women reported a depression diagnosis more often. The mean MCFSI score in the OSAS+ group was significantly higher (worse cognition) than in the OSAS- group after controlling for covariates (5.59, 95 % CI 5.08-6.11 vs. 4.29, 95 % CI 3.64-4.93, p < 0.05). CONCLUSION: Early postmenopausal women at high risk for OSAS report more CI than those at low risk for OSAS. Future studies should identify biomarkers of this CI and define the degree of reversibility of CI with OSAS treatment.
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Disfunción Cognitiva/diagnóstico , Demencia/diagnóstico , Apnea Obstructiva del Sueño/diagnóstico , Estudios de Cohortes , Comorbilidad , Trastorno Depresivo/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Pruebas Neuropsicológicas , Posmenopausia , Factores de RiesgoRESUMEN
We manipulated the degree of structural similarity between objects that had to be matched either according to whether they represented the same object (perceptual matching) or belonged to the same category (conceptual matching). Behaviorally, performance improved as a linear function of increased structural similarity during conceptual matching but deteriorated as a linear function of increased structural similarity during perceptual matching. These effects were mirrored in fMRI recordings where activation in several ventral posterior areas exhibited a similar interaction between match type and structural similarity. Our findings provide direct support for the notion that structural similarity exerts opposing effects on classification depending on whether objects are to be perceptually differentiated or categorized-a notion that has been based on rather circumstantial evidence. In particular, the finding that structural similarity plays a major role in categorization of instances according to taxonomy challenges the view that the organization of superordinate categories is not driven by shared structural features.
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Formación de Concepto/fisiología , Reconocimiento en Psicología/fisiología , Corteza Visual/fisiología , Percepción Visual/fisiología , Adolescente , Adulto , Análisis de Varianza , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Tiempo de Reacción/fisiología , Corteza Visual/irrigación sanguínea , Vías Visuales/irrigación sanguínea , Vías Visuales/fisiología , Adulto JovenRESUMEN
The monetary incentive delay (MID) task is a widely used probe for isolating neural circuitry in the human brain associated with incentive motivation. In the present functional magnetic resonance imaging (fMRI) study, 82 young adults, characterized along dimensions of impulsive sensation seeking, completed a MID task. fMRI and behavioral incentive functions were decomposed into incentive valence and magnitude parameters, which were used as predictors in linear regression to determine whether mesolimbic response is associated with problem drinking and recent alcohol use. Alcohol use was best explained by higher fMRI response to anticipation of losses and feedback on high gains in the thalamus. In contrast, problem drinking was best explained by reduced sensitivity to large incentive values in mesolimbic regions in the anticipation phase and increased sensitivity to small incentive values in the dorsal caudate nucleus in the feedback phase. Altered fMRI responses to monetary incentives in mesolimbic circuitry, particularly those alterations associated with problem drinking, may serve as potential early indicators of substance abuse trajectories.
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Afecto/fisiología , Consumo de Bebidas Alcohólicas/fisiopatología , Encéfalo/fisiología , Conducta Impulsiva/fisiología , Motivación/fisiología , Adulto , Mapeo Encefálico , Cuerpo Estriado/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Tálamo/fisiología , Adulto JovenRESUMEN
Stressful social experiences play an important role in increasing vulnerability to substance use, including cocaine. Oxytocin (OXT), known for its anxiolytic properties and involvement in social functioning, has been suggested as a potential therapeutic for cocaine use disorder (CUD). However, limited research has explored OXT's influence on social stress in CUD, and no study has examined its effects on neural response to subconscious (implicit) social threat cues in this population. To address this gap, the present study administered intranasal OXT (24 IU) or placebo (PBO) to participants with CUD (CUD+, N = 76) or without CUD (CUD-, N = 61) in a randomized parallel design. Participants then completed a functional magnetic resonance imaging (fMRI) task involving briefly presented facial fear and anger (i.e., threat) cues, followed by neutral face stimuli. Whole-brain activation and amygdala functional connectivity (using psychophysiological interaction modeling) were examined in response to the facial threat cues. OXT reduced activation in the thalamus and pontine reticular formation in response to fear cues, and in the supplementary motor area for both fear and anger cues, regardless of CUD status. Additionally, under PBO, amygdala-medial prefrontal cortex connectivity to fear stimuli was negative for the CUD+ group, but under OXT, this coupling was positive, similar to the positive coupling observed for the CUD- group under both PBO and OXT administration. The finding of OXT-mediated reversal of amygdala-prefrontal coupling was specific to CUD+ and suggests that OXT alters circuitry related to threat surveillance and implicit emotion regulation in CUD. However, additional research is needed to determine whether these alterations due to OXT have clinical significance in CUD.
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Importance: In the last 25 years, functional magnetic resonance imaging drug cue reactivity (FDCR) studies have characterized some core aspects in the neurobiology of drug addiction. However, no FDCR-derived biomarkers have been approved for treatment development or clinical adoption. Traversing this translational gap requires a systematic assessment of the FDCR literature evidence, its heterogeneity, and an evaluation of possible clinical uses of FDCR-derived biomarkers. Objective: To summarize the state of the field of FDCR, assess their potential for biomarker development, and outline a clear process for biomarker qualification to guide future research and validation efforts. Evidence Review: The PubMed and Medline databases were searched for every original FDCR investigation published from database inception until December 2022. Collected data covered study design, participant characteristics, FDCR task design, and whether each study provided evidence that might potentially help develop susceptibility, diagnostic, response, prognostic, predictive, or severity biomarkers for 1 or more addictive disorders. Findings: There were 415 FDCR studies published between 1998 and 2022. Most focused on nicotine (122 [29.6%]), alcohol (120 [29.2%]), or cocaine (46 [11.1%]), and most used visual cues (354 [85.3%]). Together, these studies recruited 19â¯311 participants, including 13â¯812 individuals with past or current substance use disorders. Most studies could potentially support biomarker development, including diagnostic (143 [32.7%]), treatment response (141 [32.3%]), severity (84 [19.2%]), prognostic (30 [6.9%]), predictive (25 [5.7%]), monitoring (12 [2.7%]), and susceptibility (2 [0.5%]) biomarkers. A total of 155 interventional studies used FDCR, mostly to investigate pharmacological (67 [43.2%]) or cognitive/behavioral (51 [32.9%]) interventions; 141 studies used FDCR as a response measure, of which 125 (88.7%) reported significant interventional FDCR alterations; and 25 studies used FDCR as an intervention outcome predictor, with 24 (96%) finding significant associations between FDCR markers and treatment outcomes. Conclusions and Relevance: Based on this systematic review and the proposed biomarker development framework, there is a pathway for the development and regulatory qualification of FDCR-based biomarkers of addiction and recovery. Further validation could support the use of FDCR-derived measures, potentially accelerating treatment development and improving diagnostic, prognostic, and predictive clinical judgments.
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Biomarcadores , Señales (Psicología) , Imagen por Resonancia Magnética , Trastornos Relacionados con Sustancias , Humanos , Trastornos Relacionados con Sustancias/fisiopatología , Trastornos Relacionados con Sustancias/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Encéfalo/metabolismo , Neuroimagen FuncionalRESUMEN
Adults' face processing expertise includes sensitivity to second-order configural information (spatial relations among features such as distance between eyes). Prior research indicates that infants process this information in female faces. In the current experiments, 9-month-olds discriminated spacing changes in upright human male and monkey faces but not in inverted faces. However, they failed to process matching changes in upright house stimuli. A similar pattern of performance was exhibited by 5-month-olds. Thus, 5- and 9-month-olds exhibited specialization by processing configural information in upright primate faces but not in houses or inverted faces. This finding suggests that, even early in life, infants treat faces in a special manner by responding to changes in configural information more readily in faces than in non-face stimuli. However, previously reported differences in infants' processing of human versus monkey faces at 9 months of age (but not at younger ages), which have been associated with perceptual narrowing, were not evident in the current study. Thus, perceptual narrowing is not absolute in the sense of loss of the ability to process information from other species' faces at older ages.
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Cara , Reconocimiento Visual de Modelos , Factores de Edad , Animales , Femenino , Humanos , Lactante , Masculino , Estimulación Luminosa , Primates , Psicología Infantil , Factores SexualesRESUMEN
Objective: The aim of this study was to determine the efficacy of doxazosin, an α1-adrenergic antagonist, for the treatment of co-occurring posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD).Methods: This 12-week, double-blind, randomized controlled trial of doxazosin (16 mg/d) was conducted between June 2016 and December 2019 at the Ralph H. Johnson VA Medical Center in Charleston, South Carolina. Participants were military veterans (N = 141) who met DSM-5 criteria for current PTSD and AUD and were randomly assigned to receive doxazosin (n = 70) or placebo (n = 71). Primary outcome measures were the Clinician Administered PTSD Scale (CAPS-5), the PTSD Checklist for DSM-5 (PCL-5), and the Timeline Follow-Back (TLFB).Results: Findings from the intent-to-treat analyses revealed that participants in both groups demonstrated statistically significant reductions in CAPS-5 and PCL-5 scores (P < .0001), but, contrary to hypotheses, no significant differences were observed between groups. Percent drinking days and percent heavy drinking days also decreased significantly during treatment, but there were no differences between groups (P < .0001). Abstinence during treatment was significantly higher in the doxazosin versus the placebo group (22% vs 7%, P = .017); however, participants in the doxazosin group consumed a greater number of drinks on drinking days (6.15 vs 4.56, P = .0096). A total of 74.5% of the sample completed the treatment phase, and there were no group differences in retention or adverse events.Conclusions: Doxazosin was safe and tolerable but was not more effective than placebo in reducing PTSD or AUD severity in this dually diagnosed sample. Clinical considerations such as heterogeneity of PTSD and AUD presentation and potential moderators are discussed in the context of future research directions.Trial Registration: ClinicalTrials.gov Identifier: NCT02500602.
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Alcoholismo , Trastornos por Estrés Postraumático , Veteranos , Humanos , Trastornos por Estrés Postraumático/complicaciones , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/tratamiento farmacológico , Doxazosina/uso terapéutico , Alcoholismo/diagnóstico , Alcoholismo/tratamiento farmacológico , Alcoholismo/epidemiología , Resultado del Tratamiento , Antagonistas de Receptores Adrenérgicos alfa 1/efectos adversos , Método Doble CiegoRESUMEN
The degree to which face-specific brain regions are specialized for different kinds of perceptual processing is debated. This study parametrically varied demands on featural, first-order configural, or second-order configural processing of faces and houses in a perceptual matching task to determine the extent to which the process of perceptual differentiation was selective for faces regardless of processing type (domain-specific account), specialized for specific types of perceptual processing regardless of category (process-specific account), engaged in category-optimized processing (i.e., configural face processing or featural house processing), or reflected generalized perceptual differentiation (i.e., differentiation that crosses category and processing type boundaries). ROIs were identified in a separate localizer run or with a similarity regressor in the face-matching runs. The predominant principle accounting for fMRI signal modulation in most regions was generalized perceptual differentiation. Nearly all regions showed perceptual differentiation for both faces and houses for more than one processing type, even if the region was identified as face-preferential in the localizer run. Consistent with process specificity, some regions showed perceptual differentiation for first-order processing of faces and houses (right fusiform face area and occipito-temporal cortex and right lateral occipital complex), but not for featural or second-order processing. Somewhat consistent with domain specificity, the right inferior frontal gyrus showed perceptual differentiation only for faces in the featural matching task. The present findings demonstrate that the majority of regions involved in perceptual differentiation of faces are also involved in differentiation of other visually homogenous categories.
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Encéfalo/fisiología , Cara , Percepción Visual/fisiología , Adolescente , Adulto , Análisis de Varianza , Conducta/fisiología , Mapeo Encefálico , Interpretación Estadística de Datos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Estimulación Luminosa , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Adulto JovenRESUMEN
Working memory is a cognitive function that is affected by aging and disease. To better understand the neural substrates for working memory, the present study examined the influence of estradiol on working memory using functional magnetic resonance imaging. Pre-menopausal women were tested on a verbal n-back task during the early (EF) and late follicular (LF) phases of the menstrual cycle. Although brain activation patterns were similar across the two phases, the most striking pattern that emerged was that estradiol had different associations with the two hemispheres. Increased activation in left frontal circuitry in the LF phase was associated with increased estradiol levels and decrements in working memory performance. In contrast, increased activation in right hemisphere regions in the LF phase was associated with improved task performance. The present study showed that better performance in the LF than the EF phase was associated with a pattern of reduced recruitment of the left-hemisphere and increased recruitment of the right-hemisphere in the LF compared to EF phase. We speculate that estradiol interferes with left-hemisphere working-memory processing in the LF phase, but that recruitment of the right hemisphere can compensate for left-hemisphere interference. This may be related to the proposal that estradiol can reduce cerebral asymmetries by modulating transcallosal communication (Hausmann, 2005).
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Encéfalo/fisiología , Estradiol/fisiología , Memoria a Corto Plazo/fisiología , Adolescente , Adulto , Interpretación Estadística de Datos , Estradiol/sangre , Femenino , Fase Folicular/fisiología , Fase Folicular/psicología , Lateralidad Funcional/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Tiempo de Reacción/fisiología , Adulto JovenRESUMEN
Greater expertise for faces in adults than in children may be achieved by a dynamic interplay of functional segregation and integration of brain regions throughout development. The present study examined developmental changes in face network functional connectivity in children (5-12 years) and adults (18-43 years) during face-viewing using a graph-theory approach. A face-specific developmental change involved connectivity of the right occipital face area. During childhood, this node increased in strength and within-module clustering based on positive connectivity. These changes reflect an important role of the ROFA in segregation of function during childhood. In addition, strength and diversity of connections within a module that included primary visual areas (left and right calcarine) and limbic regions (left hippocampus and right inferior orbitofrontal cortex) increased from childhood to adulthood, reflecting increased visuo-limbic integration. This integration was pronounced for faces but also emerged for natural objects. Taken together, the primary face-specific developmental changes involved segregation of a posterior visual module during childhood, possibly implicated in early stage perceptual face processing, and greater integration of visuo-limbic connections from childhood to adulthood, which may reflect processing related to development of perceptual expertise for individuation of faces and other visually homogenous categories.
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Mapeo Encefálico , Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Vías Nerviosas/crecimiento & desarrollo , Vías Nerviosas/fisiología , Reconocimiento Visual de Modelos/fisiología , Adolescente , Adulto , Niño , Preescolar , Cara , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Adulto JovenRESUMEN
BACKGROUND: It has been hypothesised that seizure induced neuronal loss and axonal damage in medial temporal lobe epilepsy (MTLE) may lead to the development of aberrant connections between limbic structures and eventually result in the reorganisation of the limbic network. In this study, limbic structural connectivity in patients with MTLE was investigated, using diffusion tensor MRI, probabilistic tractography and graph theory based network analysis. METHODS: 12 patients with unilateral MTLE and hippocampal sclerosis (five left and seven right MTLE) and 26 healthy controls were studied. The connectivity of 10 bilateral limbic regions of interest was mapped with probabilistic tractography, and the probabilistic fibre density between each pair of regions was used as the measure of their weighted structural connectivity. Binary connectivity matrices were then obtained from the weighted connectivity matrix using a range of fixed density thresholds. Graph theory based properties of nodes (degree, local efficiency, clustering coefficient and betweenness centrality) and the network (global efficiency and average clustering coefficient) were calculated from the weight and binary connectivity matrices of each subject and compared between patients and controls. RESULTS: MTLE was associated with a regional reduction in fibre density compared with controls. Paradoxically, patients exhibited (1) increased limbic network clustering and (2) increased nodal efficiency, degree and clustering coefficient in the ipsilateral insula, superior temporal region and thalamus. There was also a significant reduction in clustering coefficient and efficiency of the ipsilateral hippocampus, accompanied by increased nodal degree. CONCLUSIONS: These results suggest that MTLE is associated with reorganisation of the limbic system. These results corroborate the concept of MTLE as a network disease, and may contribute to the understanding of network excitability dynamics in epilepsy and MTLE.
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Epilepsia del Lóbulo Temporal/patología , Sistema Límbico/patología , Neuronas/patología , Adulto , Atrofia/patología , Mapeo Encefálico/métodos , Estudios de Casos y Controles , Imagen de Difusión Tensora/métodos , Femenino , Hipocampo/patología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Vías Nerviosas/patologíaRESUMEN
Adults' processing of own-race faces differs from that of other-race faces. The presence of an "other-race" feature (ORF) has been proposed as a mechanism underlying this specialization. We examined whether this mechanism, which was previously identified in adults and in 9-month-olds, is evident at 3.5 months. Caucasian 3.5-month-olds looked longer at a pattern containing a single Asian face among seven Caucasian faces than at a pattern containing a single Caucasian face among seven Asian faces. Homogenous and inverted face control conditions indicated that infants' preference was not driven by the majority of faces in arrays or by low-level features. Thus, 3.5-month-olds found the presence of an other-race face among own-race faces to be more salient than the reverse configuration. This asymmetry suggests sensitivity to an ORF at 3.5 months. Thus, a key mechanism of race-based processing in adults has an early onset, indicating rapid development of specialization early in life.
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Intrauterine devices (IUDs) are the most-used reversible contraceptive method for women in the world, but little is known about their potential modulation of brain function, cognition, and behavior. This is disconcerting because research on other hormonal contraceptives, especially oral contraceptives (OCs), increasingly shows that exogenous sex hormones have behavioral neuroendocrine consequences, especially for gendered cognition, including spatial skills. Effects are small and nuanced, however, partially reflecting heterogeneity. The goal of this paper is to introduce IUD use as a new frontier for basic and applied research, and to offer key considerations for studying it, emphasizing the importance of multimodal investigations and person-specific analyses. The feasibility and utility of studying IUD users is illustrated by: scanning women who completed a functional magnetic resonance imaging mental rotations task; taking an individualized approach to mapping functional connectivity during the task using network analyses containing connections common across participants and unique to individual women, focusing on brain regions in putative mental rotations and default mode networks; and linking metrics of brain connectivity from the individualized networks to both mental rotations task performance and circulating hormone levels. IUD users provide a promising natural experiment for the interplay between exogenous and endogenous sex hormones, and they are likely qualitatively different from OC users with whom they are often grouped in hormonal contraceptive research. This paper underscores how future research on IUD users can advance basic neuroendocrinological knowledge and women's health.
Asunto(s)
Dispositivos Intrauterinos , Neuroendocrinología , Anticoncepción/métodos , Femenino , HumanosRESUMEN
Social stress can contribute to the development of substance use disorders (SUDs) and increase the likelihood of relapse. Oxytocin (OT) is a potential pharmacotherapy that may buffer the effects of social stress on arousal and reward neurocircuitry. However, more research is needed to understand how OT moderates the brain's response to social stress in SUDs. The present study examined the effect of intransasal OT (24 IU) versus placebo (PBO) on corticolimbic functional connectivity associated with acute social stress in individuals with cocaine use disorder (CUD; n = 67) and healthy controls (HC; n = 52). Psychophysiological interaction modeling used the left and right amygdala as seed regions with the left and right orbitofrontal and anterior cingulate cortex as a priori regions of interest. Moderators of the OT response included childhood trauma history and biological sex, which were examined in independent analyses. The main finding was that OT normalized corticolimbic connectivity (left amygdala-orbitofrontal and left amygdala-anterior cingulate) as a function of childhood trauma such that connectivity was different between trauma-present and trauma-absent groups on PBO, but not between trauma groups on OT. Effects of OT on corticolimbic connectivity were not different as a function of diagnosis (CUD vs HC) or sex. However, OT reduced subjective anxiety during social stress for CUD participants who reported childhood trauma compared to PBO and normalized craving response as a function of sex in CUD. The present findings add to some prior findings of normalizing effects of OT on corticolimbic circuitry in individuals with trauma histories and provide some initial support that OT can normalize subjective anxiety and craving in CUD.