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1.
Biol Psychiatry Glob Open Sci ; 3(4): 875-883, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37881582

RESUMEN

Background: Physical activity is associated with mental health benefits in youth. Here, we used causal inference and triangulation with 2 levels of biology to substantiate relationships between sports participation and dimensional psychopathology in youths. Methods: Baseline data from the Adolescent Brain Cognitive Development (ABCD) Study, which recruited children from 9 to 10 years of age across the United States, were included in multilevel regression models to assess relationships between lifetime participation in team sports (TS), individual sports, and nonsports activities and Child Behavior Checklist (CBCL) scores. We calculated polygenic risk scores for 8 psychiatric disorders to assess interactions with sports exposure on CBCL scores among European descendants. Following rigorous quality control, FreeSurfer-extracted brain magnetic resonance imaging structural data were examined for mediation of CBCL-activities relationships. Results: Among those with complete data (N = 10,411), causal estimates using inverse probability weighting associated lifetime TS exposure with a 1.05-point reduction in CBCL total (95% CI, -1.54 to -0.56, p < .0001) a relationship that was specific to TS and strengthened with more years of exposure. Associations of attention-deficit/hyperactivity disorder polygenic loading with CBCL total weakened in European children with TS exposure (n = 4041; beta = -0.93, SE = 0.38, p = .013). Furthermore, TS participation and lower CBCL each associated with increased subcortical volumes (n = 8197). Subcortical volume mediated 5.5% of TS effects on CBCL total. Conclusions: Our findings support prior associations of TS participation with lower psychopathology in youths through additional studies that demonstrate specificity, dose response, and coherence across 2 levels of biology. Longitudinal studies that further clarify causal relationships may justify interventional studies of TS for high-risk youth.

2.
Nat Neurosci ; 26(6): 959-969, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37202553

RESUMEN

Childhood psychiatric symptoms are often diffuse but can coalesce into discrete mental illnesses during late adolescence. We leveraged polygenic scores (PGSs) to parse genomic risk for childhood symptoms and to uncover related neurodevelopmental mechanisms with transcriptomic and neuroimaging data. In independent samples (Adolescent Brain Cognitive Development, Generation R) a narrow cross-disorder neurodevelopmental PGS, reflecting risk for attention deficit hyperactivity disorder, autism, depression and Tourette syndrome, predicted psychiatric symptoms through early adolescence with greater sensitivity than broad cross-disorder PGSs reflecting shared risk across eight psychiatric disorders, the disorder-specific PGS individually or two other narrow cross-disorder (Compulsive, Mood-Psychotic) scores. Neurodevelopmental PGS-associated genes were preferentially expressed in the cerebellum, where their expression peaked prenatally. Further, lower gray matter volumes in cerebellum and functionally coupled cortical regions associated with psychiatric symptoms in mid-childhood. These findings demonstrate that the genetic underpinnings of pediatric psychiatric symptoms differ from those of adult illness, and implicate fetal cerebellar developmental processes that endure through childhood.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Cognición , Adolescente , Humanos , Adulto , Niño , Trastorno por Déficit de Atención con Hiperactividad/genética , Encéfalo/patología , Cerebelo/diagnóstico por imagen , Sustancia Gris
3.
bioRxiv ; 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36909456

RESUMEN

Large, population-based MRI studies of adolescents promise transformational insights into neurodevelopment and mental illness risk 1,2. However, MRI studies of youth are especially susceptible to motion and other artifacts 3,4. These artifacts may go undetected by automated quality control (QC) methods that are preferred in high-throughput imaging studies, 5 and can potentially introduce non-random noise into clinical association analyses. Here we demonstrate bias in structural MRI analyses of children due to inclusion of lower quality images, as identified through rigorous visual quality control of 11,263 T1 MRI scans obtained at age 9-10 through the Adolescent Brain Cognitive Development (ABCD) Study6. Compared to the best-rated images (44.9% of the sample), lower-quality images generally associated with decreased cortical thickness and increased cortical surface area measures (Cohen's d 0.14-2.84). Variable image quality led to counterintuitive patterns in analyses that associated structural MRI and clinical measures, as inclusion of lower-quality scans altered apparent effect sizes in ways that increased risk for both false positives and negatives. Quality-related biases were partially mitigated by controlling for surface hole number, an automated index of topological complexity that differentiated lower-quality scans with good specificity at Baseline (0.81-0.93) and in 1,000 Year 2 scans (0.88-1.00). However, even among the highest-rated images, subtle topological errors occurred during image preprocessing, and their correction through manual edits significantly and reproducibly changed thickness measurements across much of the cortex (d 0.15-0.92). These findings demonstrate that inadequate QC of youth structural MRI scans can undermine advantages of large sample size to detect meaningful associations.

4.
Schizophrenia (Heidelb) ; 8(1): 76, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36151201

RESUMEN

Cognitive impairment, and working memory deficits in particular, are debilitating, treatment-resistant aspects of schizophrenia. Dysfunction of brain network hubs, putatively related to altered neurodevelopment, is thought to underlie the cognitive symptoms associated with this illness. Here, we used weighted degree, a robust graph theory metric representing the number of weighted connections to a node, to quantify centrality in cortical hubs in 29 patients with schizophrenia and 29 age- and gender-matched healthy controls and identify the critical nodes that underlie working memory performance. In both patients and controls, elevated weighted degree in the default mode network (DMN) was generally associated with poorer performance (accuracy and reaction time). Higher degree in the ventral attention network (VAN) nodes in the right superior temporal cortex was associated with better performance (accuracy) in patients. Degree in several prefrontal and parietal areas was associated with cognitive performance only in patients. In regions that are critical for sustained attention, these correlations were primarily driven by between-network connectivity in patients. Moreover, a cross-validated prediction analysis showed that a linear model using a summary degree score can be used to predict an individual's working memory accuracy (r = 0.35). Our results suggest that schizophrenia is associated with dysfunctional hubs in the cortical systems supporting internal and external cognition and highlight the importance of topological network analysis in the search of biomarkers for cognitive deficits in schizophrenia.

5.
J Acad Consult Liaison Psychiatry ; 63(6): 619-627, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36030055

RESUMEN

Persistent symptoms following COVID-19 infection have been termed postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection. Many of these symptoms are neuropsychiatric, such as inattention, impaired memory, and executive dysfunction; these are often colloquially termed "brain fog". These symptoms are common and often persist long after the acute phase. The pattern of these deficits combined with laboratory, neuroimaging, electroencephalographic, and neuropsychological data suggest that these symptoms may be driven by direct and indirect damage to the frontal-subcortical neural networks. Here, we review this evidence, share our clinical experience at an academic medical center, and discuss potential treatment implications. While the exact etiology remains unknown, a neurocircuit-informed understanding of postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection can help guide pharmacology, neuromodulation, and physical and psychological therapeutic approaches.


Asunto(s)
COVID-19 , Disfunción Cognitiva , Humanos , SARS-CoV-2 , Progresión de la Enfermedad , Trastornos de la Memoria
6.
PLoS One ; 16(4): e0250235, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33909652

RESUMEN

OBJECTIVE: Numerous adverse prenatal exposures have been individually associated with risk for psychiatric illness in the offspring. However, such exposures frequently co-occur, raising questions about their cumulative impact. We evaluated effects of cumulative adverse prenatal exposure burden on psychopathology risk in school-aged children. METHODS: Using baseline surveys from the U.S.-based Adolescent Brain and Cognitive Development (ABCD) Study (7,898 non-adopted, unrelated children from 21 sites, age 9-10, and their primary caregivers), we examined 8 retrospectively-reported adverse prenatal exposures in relation to caregiver-reported total and subscale Child Behavior Checklist (CBCL) scores. We also assessed cumulative effects of these factors on CBCL total as a continuous measure, as well as on odds of clinically significant psychopathology (CBCL total ≥60), in both the initial set and a separate ABCD sample comprising an additional 696 sibling pairs. Analyses were conducted before and after adjustment for 14 demographic and environmental covariates. RESULTS: In minimally and fully adjusted models, 6 exposures (unplanned pregnancy; maternal alcohol, marijuana, and tobacco use early in pregnancy; pregnancy complications; and birth complications) independently associated with significant but small increases in CBCL total score. Among these 6, none increased the odds of crossing the threshold for clinically significant symptoms by itself. However, odds of exceeding this threshold became significant with 2 exposures (OR = 1.86, 95% CI 1.47-2.36), and increased linearly with each level of exposure (OR = 1.39, 95% CI 1.31-1.47), up to 3.53-fold for ≥4 exposures versus none. Similar effects were observed in confirmatory analysis among siblings. Within sibling pairs, greater discordance for exposure load associated with greater CBCL total differences, suggesting that results were not confounded by unmeasured family-level effects. CONCLUSION: Children exposed to multiple common, adverse prenatal events showed dose-dependent increases in broad, clinically significant psychopathology at age 9-10. Fully prospective studies are needed to confirm and elaborate upon this pattern.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Desarrollo Infantil/fisiología , Cognición/fisiología , Trastornos Mentales/psicología , Efectos Tardíos de la Exposición Prenatal/psicología , Encéfalo/fisiopatología , Niño , Femenino , Humanos , Trastornos Mentales/fisiopatología , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Factores de Riesgo
7.
Mol Psychiatry ; 26(6): 2493-2503, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33462330

RESUMEN

Contemporary models of psychosis suggest that a continuum of severity of psychotic symptoms exists, with subthreshold psychotic experiences (PEs) potentially reflecting some genetic and environmental risk factors shared with clinical psychosis. Thus, identifying abnormalities in brain activity that manifest across this continuum can shed new light on the pathophysiology of psychosis. Here, we investigated the moment-to-moment engagement of brain networks ("states") in individuals with schizophrenia (SCZ) and PEs and identified features of these states that are associated with psychosis-spectrum symptoms. Transient brain states were defined by clustering "single snapshots" of blood oxygen level-dependent images, based on spatial similarity of the images. We found that individuals with SCZ (n = 35) demonstrated reduced recruitment of three brain states compared to demographically matched healthy controls (n = 35). Of these three illness-related states, one specific state, involving primarily the visual and salience networks, also occurred at a lower rate in individuals with persistent PEs (n = 22), compared to demographically matched healthy youth (n = 22). Moreover, the occurrence rate of this marker brain state was negatively correlated with the severity of PEs (r = -0.26, p = 0.003, n = 130). In contrast, the spatial map of this state appeared to be unaffected in the SCZ or PE groups. Thus, reduced engagement of a brain state involving the visual and salience networks was demonstrated across the psychosis continuum, suggesting that early disruptions of perceptual and affective function may underlie some of the core symptoms of the illness.


Asunto(s)
Trastornos Psicóticos , Esquizofrenia , Adolescente , Encéfalo , Humanos , Imagen por Resonancia Magnética
8.
Neuroimage ; 217: 116895, 2020 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-32360929

RESUMEN

Working memory engages multiple distributed brain networks to support goal-directed behavior and higher order cognition. Dysfunction in working memory has been associated with cognitive impairment in neuropsychiatric disorders. It is important to characterize the interactions among cortical networks that are sensitive to working memory load since such interactions can also hint at the impaired dynamics in patients with poor working memory performance. Functional connectivity is a powerful tool used to investigate coordinated activity among local and distant brain regions. Here, we identified connectivity footprints that differentiate task states representing distinct working memory load levels. We employed linear support vector machines to decode working memory load from task-based functional connectivity matrices in 177 healthy adults. Using neighborhood component analysis, we also identified the most important connectivity pairs in classifying high and low working memory loads. We found that between-network coupling among frontoparietal, ventral attention and default mode networks, and within-network connectivity in ventral attention network are the most important factors in classifying low vs. high working memory load. Task-based within-network connectivity profiles at high working memory load in ventral attention and default mode networks were the most predictive of load-related increases in response times. Our findings reveal the large-scale impact of working memory load on the cerebral cortex and highlight the complex dynamics of intrinsic brain networks during active task states.


Asunto(s)
Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiología , Aprendizaje Automático , Memoria a Corto Plazo/fisiología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiología , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Máquina de Vectores de Soporte , Adulto Joven
9.
JAMA Psychiatry ; 75(9): 918-928, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29971329

RESUMEN

Importance: Presently, 81 countries mandate the fortification of grain products with folic acid to lessen the risk of neural tube defects in the developing fetus. Epidemiologic data on severe mental illness suggest potentially broader effects of prenatal folate exposure on postnatal brain development, but this link remains unsubstantiated by biological evidence. Objective: To evaluate associations among fetal folic acid exposure, cortical maturation, and psychiatric risk in youths. Design, Setting, and Participants: A retrospective, observational clinical cohort study was conducted at Massachusetts General Hospital (MGH) among 292 youths 8 to 18 years of age born between January 1993 and December 2001 (inclusive of folic acid fortification rollout ±3.5 years) with normative results of clinical magnetic resonance imaging, divided into 3 age-matched groups based on birthdate and related level of prenatal folic acid fortification exposure (none, partial, or full). Magnetic resonance imaging was performed between January 2005 and March 2015. Two independent, observational, community-based cohorts (Philadelphia Neurodevelopmental Cohort [PNC] and National Institutes of Health Magnetic Resonance Imaging Study of Normal Brain Development [NIH]) comprising 1078 youths 8 to 18 years of age born throughout (PNC, 1992-2003) or before (NIH, 1983-1995) the rollout of folic acid fortification were studied for replication, clinical extension, and specificity. Statistical analysis was conducted from 2015 to 2018. Exposures: United States-mandated grain product fortification with folic acid, introduced in late 1996 and fully in effect by mid-1997. Main Outcomes and Measures: Differences in cortical thickness among nonexposed, partially exposed, and fully exposed youths (MGH) and underlying associations between age and cortical thickness (all cohorts). Analysis of the PNC cohort also examined the association of age-cortical thickness slopes with the odds of psychotic symptoms. Results: The MGH cohort (139 girls and 153 boys; mean [SD] age, 13.3 [2.3] years) demonstrated exposure-associated cortical thickness increases in bilateral frontal and temporal regions (9.9% to 11.6%; corrected P < .001 to P = .03) and emergence of quadratic (delayed) age-associated thinning in temporal and parietal regions (ß = -11.1 to -13.9; corrected P = .002). The contemporaneous PNC cohort (417 girls and 444 boys; mean [SD] age, 13.5 [2.7] years) also exhibited exposure-associated delays of cortical thinning (ß = -1.59 to -1.73; corrected P < .001 to P = .02), located in similar regions and with similar durations of delay as in the MGH cohort. Flatter thinning profiles in frontal, temporal, and parietal regions were associated with lower odds of psychosis spectrum symptoms in the PNC cohort (odds ratio, 0.37-0.59; corrected P < .05). All identified regions displayed earlier thinning in the nonexposed NIH cohort (118 girls and 99 boys; mean [SD] age, 13.3 [2.6] years). Conclusions and Relevance: The results of this study suggest an association between gestational exposure to fortification of grain products with folic acid and altered cortical development and, in turn, with reduction in the risk of psychosis in youths.


Asunto(s)
Corteza Cerebral , Ácido Fólico/farmacología , Alimentos Fortificados , Defectos del Tubo Neural/prevención & control , Vigilancia de la Población , Efectos Tardíos de la Exposición Prenatal , Adolescente , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/crecimiento & desarrollo , Niño , Correlación de Datos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Massachusetts , Philadelphia , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/diagnóstico , Complejo Vitamínico B/farmacología
10.
Nutrients ; 9(9)2017 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-28885600

RESUMEN

Since 1998, the U.S. has mandated folic acid (FA) fortification of certain grain products to reduce the risk of neural tube defects. Folate intake and red blood cell (RBC) folate concentrations increased substantially post-intervention, although recent studies raise concerns about the level of ongoing benefit. This study investigated blood folate level determinants in healthy young adults, including intake of naturally occurring food folate, synthetic FA, and the interaction of naturally occurring food folate with a common missense variant in the FOLH1 gene thought to affect absorption. Participants (n = 265) completed the Diet History Questionnaire II, RBC folate testing, and were genotyped for the 484T>C FOLH1 variant. Men reported significantly greater intake of all folate sources except for supplemental FA, but RBC folate levels did not significantly differ by sex. Synthetic FA was a stronger predictor of RBC folate than naturally occurring food folate. In the largest racial group, synthetic FA and the interaction of FOLH1 genotype with naturally occurring food folate significantly predicted RBC folate, with the overall model accounting for 13.8% of the variance in RBC folate levels. Blood folate levels rely on a complex interaction of natural and synthetic folate intake as well as FOLH1 genotype.


Asunto(s)
Dieta , Ácido Fólico/sangre , Adolescente , Adulto , Estudios Transversales , Suplementos Dietéticos , Femenino , Deficiencia de Ácido Fólico/sangre , Alimentos Fortificados , Humanos , Masculino , Necesidades Nutricionales , Estado Nutricional , Adulto Joven
11.
Sci Rep ; 7(1): 6002, 2017 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-28729647

RESUMEN

Instrumental learning is mediated by goal-directed and habit systems in the brain. While rodent studies implicate distinct prefrontal/striatal regions in goal-directed and habit learning, neural systems underpinning these two processes in humans remain poorly understood. Here, using a validated discrimination learning task that distinguishes goal-directed learning from habit learning in 72 subjects in fMRI, we investigated the corticostriatal correlates of goal-directed learning and tested whether brain activation during learning is associated with trait motivation and behavioral performance in the post-learning test phase. Participants showed enhanced activation in medial prefrontal and posterior cingulate cortices during goal-directed action selection in the training phase, whereas habitual action selection activated bilateral insula, bilateral dorsal caudate and left precentral gyrus. In addition, early phase of learning was associated with increased activation in the frontoparietal control network and dorsal striatum, whereas default mode regions depicted increased activation in the late phase. Finally, avoidance motivation scores measured by Behavioral Inhibition/Activation System (BIS/BAS) correlated with accuracy during goal-directed learning and showed a nominally significant correlation with activation in dorsomedial prefrontal cortex during goal-directed acquisition of stimuli. These findings reveal the temporal dynamics of instrumental behavior and suggest that avoidance motivation predicts performance and brain activity during goal-directed learning.


Asunto(s)
Encéfalo/fisiología , Objetivos , Hábitos , Motivación , Adulto , Mapeo Encefálico , Femenino , Humanos , Modelos Lineales , Masculino
13.
Sci Adv ; 2(6): e1501672, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27386561

RESUMEN

Local prefrontal dopamine signaling supports working memory by tuning pyramidal neurons to task-relevant stimuli. Enabled by simultaneous positron emission tomography-magnetic resonance imaging (PET-MRI), we determined whether neuromodulatory effects of dopamine scale to the level of cortical networks and coordinate their interplay during working memory. Among network territories, mean cortical D1 receptor densities differed substantially but were strongly interrelated, suggesting cross-network regulation. Indeed, mean cortical D1 density predicted working memory-emergent decoupling of the frontoparietal and default networks, which respectively manage task-related and internal stimuli. In contrast, striatal D1 predicted opposing effects within these two networks but no between-network effects. These findings specifically link cortical dopamine signaling to network crosstalk that redirects cognitive resources to working memory, echoing neuromodulatory effects of D1 signaling on the level of cortical microcircuits.


Asunto(s)
Corteza Cerebral/fisiología , Dopamina/metabolismo , Memoria a Corto Plazo , Red Nerviosa , Receptores de Dopamina D1/metabolismo , Transducción de Señal , Adolescente , Adulto , Cuerpo Estriado/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Adulto Joven
14.
Neuropsychopharmacology ; 41(9): 2411-20, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27103065

RESUMEN

Working memory (WM) impairment, a core feature of schizophrenia, is often associated with aberrant dorsolateral prefrontal cortex (dlPFC) activation. Reduced resting-state connectivity within the frontoparietal control network (FPCN) has also been reported in schizophrenia. However, interpretation of WM-related dlPFC dysfunction has been limited by performance differences between patients and controls, and by uncertainty over the relevance of resting-state connectivity to network engagement during task. We contrasted brain activation in 40 schizophrenia patients and 40 controls during verbal WM performance, and evaluated underlying functional connectivity during rest and task. During correct trials, patients demonstrated normal FPCN activation, despite an inverse relationship between positive symptoms and activation. FPCN activation differed between the groups only during error trials (controls>patients). In contrast, controls demonstrated stronger deactivation of the ventromedial prefrontal cortex (vmPFC) during correct and error trials. Functional connectivity analysis indicated impaired resting-state FPCN connectivity in patients, but normal connectivity during task. However, patients showed abnormal connectivity among regions such as vmPFC, lateral orbitofrontal cortex, and parahippocampal gyrus (PHG) during both rest and task. During task, patients also exhibited altered thalamic connectivity to PHG and FPCN. Activation and connectivity patterns that were more characteristic of controls generally correlated with better performance. In summary, patients demonstrated normal FPCN activation when they remained on-task, and exhibited normal FPCN connectivity during WM, whereas vmPFC deactivation differences persisted regardless of WM performance. Our findings suggest that altered FPCN activation in patients reflects performance difference, and that limbic and thalamic dysfunction is critically involved in WM deficits in schizophrenia.


Asunto(s)
Encéfalo/fisiopatología , Memoria a Corto Plazo/fisiología , Esquizofrenia/fisiopatología , Psicología del Esquizofrénico , Adulto , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiopatología , Corteza Prefrontal/fisiopatología
15.
Soc Cogn Affect Neurosci ; 10(2): 180-90, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24603023

RESUMEN

Inertia, together with intensity and valence, is an important component of emotion. We tested whether positive and negative events generate lingering changes in subsequent brain responses to unrelated threat stimuli and investigated the impact of individual anxiety. We acquired fMRI data while participants watched positive or negative movie-clips and subsequently performed an unrelated task with fearful and neutral faces. We quantified changes in amygdala reactivity to fearful faces as a function of the valence of preceding movies and cumulative neural activity evoked during them. We demonstrate that amygdala responses to emotional movies spill over to subsequent processing of threat information in a valence-specific manner: negative movies enhance later amygdala activation whereas positive movies attenuate it. Critically, the magnitude of such changes is predicted by a measure of cumulative amygdala responses to the preceding positive or negative movies. These effects appear independent of overt attention, are regionally limited to amygdala, with no changes in functional connectivity. Finally, individuals with higher state anxiety displayed stronger modulation of amygdala reactivity by positive movies. These results suggest that intensity and valence of emotional events as well as anxiety levels promote local changes in amygdala sensitivity to threat, highlighting the importance of past experience in shaping future affective reactivity.


Asunto(s)
Amígdala del Cerebelo/fisiopatología , Ansiedad/fisiopatología , Ansiedad/psicología , Atención , Emociones , Cara , Miedo/psicología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiopatología , Estimulación Luminosa , Desempeño Psicomotor , Tiempo de Reacción , Reflejo Pupilar , Adulto Joven
16.
J Neurosci ; 34(23): 7825-35, 2014 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-24899706

RESUMEN

Obtaining lower gains than rejected alternatives during decision making evokes feelings of regret, whereas higher gains elicit gratification. Although decision-related emotions produce lingering effects on mental state, neuroscience research has generally focused on transient brain responses to positive or negative events, but ignored more sustained consequences of emotional episodes on subsequent brain states. We investigated how spontaneous brain activity and functional connectivity at rest are modulated by postdecision regret and gratification in 18 healthy human subjects using a gambling task in fMRI. Differences between obtained and unobtained outcomes were manipulated parametrically to evoke different levels of regret or gratification. We investigated how individual personality traits related to depression and rumination affected these responses. Medial and ventral prefrontal areas differentially responded to favorable and unfavorable outcomes during the gambling period. More critically, during subsequent rest, rostral anterior and posterior cingulate cortex, ventral striatum, and insula showed parametric response to the gratification level of preceding outcomes. Functional coupling of posterior cingulate with striatum and amygdala was also enhanced during rest after high gratification. Regret produced distinct changes in connectivity of subgenual cingulate with orbitofrontal cortex and thalamus. Interestingly, individual differences in depressive traits and ruminations correlated with activity of the striatum after gratification and orbitofrontal cortex after regret, respectively. By revealing lingering effects of decision-related emotions on key nodes of resting state networks, our findings illuminate how such emotions may influence self-reflective processing and subsequent behavioral adjustment, but also highlight the malleability of resting networks in emotional contexts.


Asunto(s)
Encéfalo/fisiopatología , Depresión/patología , Emociones/fisiología , Placer/fisiología , Descanso/fisiología , Adulto , Encéfalo/irrigación sanguínea , Conducta de Elección/fisiología , Femenino , Juegos Experimentales , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Personalidad , Encuestas y Cuestionarios , Adulto Joven
17.
Neuroimage ; 54(3): 2481-91, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20955802

RESUMEN

The functional properties of resting brain activity are poorly understood, but have generally been related to self-monitoring and introspective processes. Here we investigated how emotionally positive and negative information differentially influenced subsequent brain activity at rest. We acquired fMRI data in 15 participants during rest periods following fearful, joyful, and neutral movies. Several brain regions were more active during resting than during movie-watching, including posterior/anterior cingulate cortices (PCC, ACC), bilateral insula and inferior parietal lobules (IPL). Functional connectivity at different frequency bands was also assessed using a wavelet correlation approach and small-world network analysis. Resting activity in ACC and insula as well as their coupling were strongly enhanced by preceding emotions, while coupling between ventral-medial prefrontal cortex and amygdala was selectively reduced. These effects were more pronounced after fearful than joyful movies for higher frequency bands. Moreover, the initial suppression of resting activity in ACC and insula after emotional stimuli was followed by a gradual restoration over time. Emotions did not affect IPL average activity but increased its connectivity with other regions. These findings reveal specific neural circuits recruited during the recovery from emotional arousal and highlight the complex functional dynamics of default mode networks in emotionally salient contexts.


Asunto(s)
Emociones/fisiología , Red Nerviosa/fisiología , Vías Nerviosas/fisiología , Adolescente , Adulto , Encéfalo/fisiología , Corteza Cerebral/fisiología , Miedo/fisiología , Femenino , Felicidad , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Modelos Neurológicos , Películas Cinematográficas , Descanso/fisiología , Análisis de Ondículas , Adulto Joven
18.
Neuroimage ; 56(2): 616-26, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20541019

RESUMEN

Functional connectivity analysis of fMRI data can reveal synchronised activity between anatomically distinct brain regions. Here, we extract the characteristic connectivity signatures of different brain states to perform classification, allowing us to decode the different states based on the functional connectivity patterns. Our approach is based on polythetic decision trees, which combine powerful discriminative ability with interpretability of results. We also propose to use ensemble of classifiers within specific frequency subbands, and show that they bring systematic improvement in classification accuracy. Exploiting multi-band classification of connectivity graphs is also proposed, and we explain theoretical reasons why the technique could bring further improvement in classification performance. The choice of decision trees as classifier is shown to provide a practical way to identify a subset of connections that distinguishes best between the conditions, permitting the extraction of very compact representations for differences between brain states, which we call discriminative graphs. Our experimental results based on strict train/test separation at all stages of processing show that the method is applicable to inter-subject brain decoding with relatively low error rates for the task considered.


Asunto(s)
Inteligencia Artificial , Mapeo Encefálico/métodos , Encéfalo/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Encéfalo/anatomía & histología , Árboles de Decisión , Humanos , Red Nerviosa/anatomía & histología , Red Nerviosa/fisiología
19.
Artículo en Inglés | MEDLINE | ID: mdl-18003189

RESUMEN

Functional neuroimaging studies can be performed by combining the modalities of fMRI and Electroencephalography because of their complementary properties. The main advantage of EEG imaging among other modalities is the high temporal resolution while fMRI has high spatial resolution. So, usage of these procedures is going to help us to gain more information about the functional organization of the brain. In this study, changes in the relationship between Steady State Visual Evoked Potentials (SSVEP) generators and BOLD responses during visual stimulation have been systematically studied with 5 stimulus presentation rates (2, 4, 6, 8, 10) between 2-10 Hz. fMRI Analysis was carried out using Statistical Parametric Mapping (SPM). The result of fMRI analysis is used as a localization mask for SSVEP localization process. SSVEP generators are localized using Low Resolution Electro Magnetic Tomography (LORETA) which is implemented on a realistic head model. Then, for each stimulus frequency voxel by voxel correlation values of the active regions are computed.


Asunto(s)
Mapeo Encefálico/métodos , Potenciales Evocados Visuales/fisiología , Imagen por Resonancia Magnética/métodos , Modelos Neurológicos , Reconocimiento de Normas Patrones Automatizadas/métodos , Tomografía/métodos , Corteza Visual/fisiología , Algoritmos , Inteligencia Artificial , Simulación por Computador , Interpretación Estadística de Datos , Cabeza/fisiología , Humanos
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