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1.
Int J Mol Sci ; 16(7): 14640-54, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26132568

RESUMO

Individuals in the early phases of psychotic illness have disturbed metacognitive capacity, which has been linked to a number of poor outcomes. Little is known, however, about the neural systems associated with metacognition in this population. The purpose of this study was to elucidate the neuroanatomical correlates of metacognition. We anticipated that higher levels of metacognition may be dependent upon gray matter density (GMD) of regions within the prefrontal cortex. Examining whole-brain structure in 25 individuals with early phase psychosis, we found positive correlations between increased medial prefrontal cortex and ventral striatum GMD and higher metacognition. These findings represent an important step in understanding the path through which the biological correlates of psychotic illness may culminate into poor metacognition and, ultimately, disrupted functioning. Such a path will serve to validate and promote metacognition as a viable treatment target in early phase psychosis.


Assuntos
Metacognição , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Corpo Estriado/fisiopatologia , Feminino , Substância Cinzenta/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/fisiopatologia , Transtornos Psicóticos/diagnóstico , Esquizofrenia/diagnóstico
2.
Brain Cogn ; 88: 26-34, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24836970

RESUMO

Prior research has indicated that self-reported violent media exposure is associated with poorer performance on some neuropsychological tests in adolescents. This study aimed to examine the relationship of executive functioning to violent television viewing in healthy young adult males and examine how brain structure is associated with media exposure measures. Sixty-five healthy adult males (ages 18-29) with minimal video game experience estimated their television viewing habits over the past year and, during the subsequent week, recorded television viewing time and characteristics in a daily media diary. Participants then completed a battery of neuropsychological laboratory tests quantifying executive functions and underwent a magnetic resonance imaging (MRI) scan. Aggregate measures of executive functioning were not associated with measures of overall television viewing (any content type) during the past week or year. However, the amount of television viewing of violent content only, as indicated by both past-year and daily diary measures, was associated with poorer scores on an aggregate score of inhibition, interference control and attention, with no relationship to a composite working memory score. In addition, violent television exposure, as measured with daily media diaries, was associated with reduced frontoparietal white matter volume. Future longitudinal work is necessary to resolve whether individuals with poor executive function and slower white matter growth are more drawn to violent programming, or if extensive media violence exposure modifies cognitive control mechanisms mediated primarily via prefrontal cortex. Impaired inhibitory mechanisms may be related to reported increases in aggression with higher media violence exposure.


Assuntos
Encéfalo/anatomia & histologia , Função Executiva , Televisão , Violência , Substância Branca/anatomia & histologia , Adolescente , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Testes Neuropsicológicos , Teste de Stroop , Inquéritos e Questionários , Violência/psicologia , Adulto Jovem
3.
Curr Addict Rep ; 11(2): 287-298, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606363

RESUMO

Purpose of Review: The incorporation of digital technologies and their use in youth's everyday lives has been increasing rapidly over the past several decades with possible impacts on youth development and mental health. This narrative review aimed to consider how the use of digital technologies may be influencing brain development underlying adaptive and maladaptive screen-related behaviors. Recent Findings: To explore and provide direction for further scientific inquiry, an international group of experts considered what is known, important gaps in knowledge, and how a research agenda might be pursued regarding relationships between screen media activity and neurodevelopment from infancy through childhood and adolescence. While an understanding of brain-behavior relationships involving screen media activity has been emerging, significant gaps exist that have important implications for the health of developing youth. Summary: Specific considerations regarding brain-behavior relationships involving screen media activity exist for infancy, toddlerhood, and early childhood; middle childhood; and adolescence. Transdiagnostic frameworks may provide a foundation for guiding future research efforts. Translating knowledge gained into better interventions and policy to promote healthy development is important in a rapidly changing digital technology environment.

4.
Neuroimage ; 83: 646-57, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23831414

RESUMO

High-resolution isotropic three-dimensional reconstructions of human brain gray and white matter structures can be characterized to quantify aspects of their shape, volume and topological complexity. In particular, methods based on fractal analysis have been applied in neuroimaging studies to quantify the structural complexity of the brain in both healthy and impaired conditions. The usefulness of such measures for characterizing individual differences in brain structure critically depends on their within-subject reproducibility in order to allow the robust detection of between-subject differences. This study analyzes key analytic parameters of three fractal-based methods that rely on the box-counting algorithm with the aim to maximize within-subject reproducibility of the fractal characterizations of different brain objects, including the pial surface, the cortical ribbon volume, the white matter volume and the gray matter/white matter boundary. Two separate datasets originating from different imaging centers were analyzed, comprising 50 subjects with three and 24 subjects with four successive scanning sessions per subject, respectively. The reproducibility of fractal measures was statistically assessed by computing their intra-class correlations. Results reveal differences between different fractal estimators and allow the identification of several parameters that are critical for high reproducibility. Highest reproducibility with intra-class correlations in the range of 0.9-0.95 is achieved with the correlation dimension. Further analyses of the fractal dimensions of parcellated cortical and subcortical gray matter regions suggest robustly estimated and region-specific patterns of individual variability. These results are valuable for defining appropriate parameter configurations when studying changes in fractal descriptors of human brain structure, for instance in studies of neurological diseases that do not allow repeated measurements or for disease-course longitudinal studies.


Assuntos
Algoritmos , Encéfalo/anatomia & histologia , Fractais , Processamento de Imagem Assistida por Computador/métodos , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
5.
Epilepsy Behav ; 26(3): 295-302, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23200700

RESUMO

Children with epilepsy are at risk for behavioral and cognitive comorbidities. Potential etiologies can be assessed in part by neuroimaging. Functional magnetic resonance imaging (MRI) has a major role in presurgical evaluation and prediction of postoperative outcome by mapping of language and memory. Structural MRI and functional MRI have shown changes in children and adolescents with attention deficit hyperactivity disorder and disruptive behavior, common comorbidities in children with epilepsy. Neuroimaging has the potential for significantly increasing understanding of the basis of cognitive and behavioral problems in children with epilepsy.


Assuntos
Epilepsia/epidemiologia , Epilepsia/patologia , Imageamento por Ressonância Magnética , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Mapeamento Encefálico , Criança , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Comorbidade , Humanos , Processamento de Imagem Assistida por Computador , Transtornos da Memória/diagnóstico , Transtornos da Memória/epidemiologia , Oxigênio/sangue
6.
Games Health J ; 12(1): 53-62, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36301265

RESUMO

Background: Continuous advances in virtual reality (VR) technology have increased its potential for clinical use in the research, assessment, and treatment of mental health difficulties. One potential target for VR use is childhood behavior problems, which are often associated with social-cognitive deficits that can be difficult to measure or modify. Materials and Methods: We enrolled 36 boys between the ages of 8-13 to assess the usability of a VR device and its feasibility as a psychiatric tool for youth. Each participant experienced three virtual school cafeteria scenes that varied in antisocial content and the intentions of a virtual counterpart (VC) (control, ambiguous, or hostile). Following each scene, participants completed questions about ease and comfort in using the headset as well as an assessment of hostile attribution bias (HAB). HAB is the tendency to attribute hostile motivations to others' behaviors, which contributes to antisocial thoughts and behaviors. Following this VR use, participants completed a standard text assessment of HAB. Results: In general, participants reported the VR headset to be enjoyable and easy to use, and scenes worked as intended, with VCs in the hostile scene rated the meanest. In addition, boys with more conduct problems reported that virtual characters were meaner to them, despite no difference in text vignette measures of HAB. Conclusion: This study provides preliminary evidence supporting the further development of VR programs to assess and treat childhood behavior problems.


Assuntos
Comportamento Problema , Realidade Virtual , Masculino , Adolescente , Humanos , Criança , Relações Interpessoais , Percepção Social , Motivação
7.
PLoS One ; 18(1): e0280082, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36638090

RESUMO

Δ 4,16-androstadien-3-one (androstadienone) is a putative human pheromone often linked to sexual attraction in young adults, although specific associations with sexual behavior are not yet established. Androstadienone also serves a broader social-emotional function beyond the sexual domain, specifically tuning the brain to efficiently process emotional information. Whether these effects persist throughout the lifespan into post-reproductive life is unknown. In a laboratory study of older adults, those with greater androstadienone odor sensitivity paid greater attention to subliminal emotional information, specifically, angry faces (p = 0.05), with a similar relationship to happy faces. In contrast, the physical odor n-butanol (a control) did not affect emotional attention (p = 0.49). We then extended this laboratory research and determined whether sensitivity to androstadienone affects the everyday lives of older adults by measuring their social and sexual behavior. In this second study, we surveyed in a nationally representative sample of US older adults living in their homes (National Social Life and Aging Project, 62-90 years; n = 2,086), along with their sensitivity to androstadienone, general olfactory function, health and demographics. Greater sensitivity to androstadienone was associated with richer social lives: having more friends, increased communication with close friends and family, and more participation in organized social events and volunteer activities (all p's ≤ 0.05, generalized linear models, adjusted for age and gender). It was also associated with more recent sexual activity, more frequent sexual thoughts, and viewing sex as an important part of life (all p's ≤ 0.05). General olfactory function did not explain these associations, supporting a specialized function for this pheromone during everyday life, and expanding its role to social life as well as sexual behavior, likely mediated by enhanced attention to emotional information.


Assuntos
Emoções , Interação Social , Adulto Jovem , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Comportamento Sexual , Odorantes , Ira
8.
Front Neuroimaging ; 2: 1110494, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554652

RESUMO

Background: Risky decision-making is associated with the development of substance use behaviors during adolescence. Although prior work has investigated risky decision-making in adolescents at familial high risk for developing substance use disorders (SUDs), little research has controlled for the presence of co-morbid externalizing disorders (EDs). Additionally, few studies have investigated the role of parental impulsivity in offspring neurobiology associated with risky decision-making. Methods: One-hundred twenty-five children (28 healthy controls, 47 psychiatric controls with EDs without a familial history of SUD, and 50 high-risk children with co-morbid EDs with a familial history of SUD) participated in the Balloon Analog Risk Task while undergoing functional magnetic resonance imaging. Impulsivity for parents and children was measured using the UPPS-P Impulsive Behavior Scale. Results: We found that individuals in the psychiatric control group showed greater activation, as chances of balloon explosion increased, while making choices, relative to the healthy control and high-risk groups in the rostral anterior cingulate cortex (rACC) and lateral orbitofrontal cortex (lOFC). We also found a positive association between greater activation and parental impulsivity in these regions. However, within rACC, this relationship was moderated by group, such that there was a positive relationship between activation and parental impulsivity in the HC group, but an inverse relationship in the HR group. Conclusions: These findings suggest that there are key differences in the neurobiology underlying risky decision-making in individuals with EDs with and without a familial history of SUD. The current findings build on existing models of neurobiological factors influencing addiction risk by integrating parental factors. This work paves the way for more precise risk models in which to test preventive interventions.

9.
Neuroimage ; 61(4): 1153-64, 2012 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-22450298

RESUMO

Structural brain networks were constructed based on diffusion tensor imaging (DTI) data of 59 young healthy male adults. The networks had 68 nodes, derived from FreeSurfer parcellation of the cortical surface. By means of streamline tractography, the edge weight was defined as the number of streamlines between two nodes normalized by their mean volume. Specifically, two weighting schemes were adopted by considering various biases from fiber tracking. The weighting schemes were tested for possible bias toward the physical size of the nodes. A novel thresholding method was proposed using the variance of number of streamlines in fiber tracking. The backbone networks were extracted and various network analyses were applied to investigate the features of the binary and weighted backbone networks. For weighted networks, a high correlation was observed between nodal strength and betweenness centrality. Despite similar small-worldness features, binary networks and weighted networks are distinctive in many aspects, such as modularity and nodal betweenness centrality. Inter-subject variability was examined for the weighted networks, along with the test-retest reliability from two repeated scans on 44 of the 59 subjects. The inter-/intra-subject variability of weighted networks was discussed in three levels - edge weights, local metrics, and global metrics. The variance of edge weights can be very large. Although local metrics show less variability than the edge weights, they still have considerable amounts of variability. Weighting scheme one, which scales the number of streamlines by their lengths, demonstrates stable intra-class correlation coefficients against thresholding for global efficiency, clustering coefficient and diversity. The intra-class correlation analysis suggests the current approach of constructing weighted network has a reasonably high reproducibility for most global metrics.


Assuntos
Mapeamento Encefálico/métodos , Imagem de Tensor de Difusão/métodos , Interpretação de Imagem Assistida por Computador/métodos , Encéfalo/anatomia & histologia , Humanos , Masculino , Rede Nervosa/anatomia & histologia , Adulto Jovem
10.
Psychiatry Res ; 202(3): 245-51, 2012 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-22743120

RESUMO

Disruptive behavior disorders (DBD) are among the most commonly diagnosed mental disorders in children and adolescents. Some important characteristics of DBD vary based on the presence or absence of comorbid attention-deficit/hyperactivity disorder (ADHD), which may affect the understanding of and treatment decision-making related to the disorders. Thus, identifying neurobiological characteristics of DBD with comorbid ADHD (DBD+ADHD) can provide a basis to establish a better understanding of the condition. This study aimed to assess abnormal white matter microstructural alterations in DBD+ADHD as compared to DBD alone and healthy controls using diffusion tensor imaging (DTI). Thirty-three DBD (19 with comorbid ADHD) and 46 age-matched healthy adolescents were studied using DTI. Fractional anisotropy (FA), and mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD) were analyzed using tract-based spatial statistics (TBSS). Significantly lower FA and higher MD, RD and AD in many white matter fibers were found in adolescents with DBD+ADHD compared to controls. Moreover, lower FA and higher RD were also found in the DBD+ADHD versus the DBD alone group. Alterations of white matter integrity found in DBD patients were primarily associated with ADHD, suggesting that ADHD comorbidity in DBD is reflected in greater abnormality of microstructural connections.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/complicações , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/patologia , Mapeamento Encefálico , Encéfalo/patologia , Fibras Nervosas Mielinizadas/patologia , Adolescente , Anisotropia , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento Tridimensional , Masculino , Vias Neurais/patologia
11.
Psychiatry Res ; 192(1): 12-9, 2011 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-21376543

RESUMO

Only recently have investigations of the relationship between media violence exposure (MVE) and aggressive behavior focused on brain functioning. In this study, we examined the relationship between brain activation and history of media violence exposure in adolescents, using functional magnetic resonance imaging (fMRI). Samples of adolescents with no psychiatric diagnosis or with disruptive behavior disorder (DBD) with aggression were compared to investigate whether the association of MVE history and brain activation is moderated by aggressive behavior/personality. Twenty-two adolescents with a history of aggressive behavior and diagnosis of either conduct disorder or oppositional-defiant disorder (DBD sample) and 22 controls completed an emotional Stroop task during fMRI. Primary imaging results indicated that controls with a history of low MVE demonstrated greater activity in the right inferior frontal gyrus and rostral anterior cingulate during the violent word condition. In contrast, in adolescents with DBD, those with high MVE exhibited decreased activation in the right amygdala, compared with those with low MVE. These findings are consistent with research demonstrating the importance of fronto-limbic structures for processing emotional stimuli, and with research suggesting that media violence may affect individuals in different ways depending on the presence of aggressive traits.


Assuntos
Agressão/fisiologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/patologia , Encéfalo/patologia , Emoções/fisiologia , Teste de Stroop , Violência/psicologia , Adolescente , Análise de Variância , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/fisiopatologia , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Lateralidade Funcional/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue
12.
Drug Alcohol Depend ; 219: 108498, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33440326

RESUMO

BACKGROUND: Family history (FH) of substance use disorders (SUDs) is known to elevate SUD risk in offspring. However, the influence of FH SUDs has been confounded by the effect of externalizing psychopathologies in the addiction risk neuroimaging literature. Thus, the current study aimed to assess the association between parental SUDs and offspring functional connectivity in samples matched for psychopathology and demographics. METHODS: Ninety 11-12-year-old participants with externalizing disorders were included in the study (48 FH+, 42 FH-). We conducted independent component analyses (ICA) and seed-based analyses (orbitofrontal cortex; OFC, nucleus accumbens (NAcc), dorsolateral prefrontal cortex) with resting state data. RESULTS: FH+ adolescents showed stronger functional connectivity between the right lateral OFC seed and anterior cingulate cortex compared to FH- adolescents (p < 0.05, corrected). Compared to FH-, FH+ adolescents showed stronger negative functional connectivity between the left lateral OFC seed and right postcentral gyrus and between the left NAcc seed and right middle occipital gyrus (p < 0.05, corrected). Poorer emotion regulation was associated with more negative connectivity between right occipital/left NAcc among FH+ adolescents based on the seed-based analysis. FH- adolescents had stronger negative functional connectivity between ventral attention/salience networks and dorsal attention/visuospatial networks in the ICA. CONCLUSIONS: Both analytic methods found group differences in functional connectivity between brain regions associated with executive functioning and regions associated with sensory input (e.g., postcentral gyrus, occipital regions). We speculate that families densely loaded for SUD may confer risk by altered neurocircuitry that is associated with emotion regulation and valuation of external stimuli beyond what would be explained by externalizing psychopathology alone.


Assuntos
Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Atenção , Função Executiva , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Núcleo Accumbens/fisiopatologia , Pais , Córtex Pré-Frontal/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia
13.
Neurotherapeutics ; 18(2): 827-844, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33844154

RESUMO

Schizophrenia is a complex condition associated with perceptual disturbances, decreased motivation and affect, and disrupted cognition. Individuals living with schizophrenia may experience myriad poor outcomes, including impairment in independent living and function as well as decreased life expectancy. Though existing treatments may offer benefit, many individuals still experience treatment resistant and disabling symptoms. In light of the negative outcomes associated with schizophrenia and the limitations in currently available treatments, there is a significant need for novel therapeutic interventions. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique that can modulate the activity of discrete cortical regions, allowing direct manipulation of local brain activation and indirect manipulation of the target's associated neural networks. rTMS has been studied in schizophrenia for the treatment of auditory hallucinations, negative symptoms, and cognitive deficits, with mixed results. The field's inability to arrive at a consensus on the use rTMS in schizophrenia has stemmed from a variety of issues, perhaps most notably the significant heterogeneity amongst existing trials. In addition, it is likely that factors specific to schizophrenia, rather than the rTMS itself, have presented barriers to the interpretation of existing results. However, advances in approaches to rTMS as a biologic probe and therapeutic, many of which include the integration of neuroimaging with rTMS, offer hope that this technology may still play a role in improving the understanding and treatment of schizophrenia.


Assuntos
Encéfalo/diagnóstico por imagem , Neuroimagem/tendências , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/terapia , Estimulação Magnética Transcraniana/tendências , Encéfalo/fisiopatologia , Previsões , Humanos , Neuroimagem/métodos , Neuronavegação/métodos , Neuronavegação/tendências , Esquizofrenia/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
14.
Brain Imaging Behav ; 15(4): 1802-1814, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32893328

RESUMO

Several lines of evidence have implicated white matter (WM) deficits in schizophrenia, including microstructural alterations from diffusion tensor (DTI) brain imaging studies. It has been proposed that dysregulated inflammatory processes, including heightened activity of circulating lymphocytes, may contribute to WM pathology in this illness. Fingolimod is a sphingosine-1-phosphate (S1P) receptor agonist that is approved for the treatment of relapsing multiple sclerosis (MS). Fingolimod robustly decreases the number of circulating lymphocytes through sequestration of these cells in lymph tissue. In addition, this agent improved WM microstructure as shown by increases in DTI fractional anisotropy (FA). In this pilot study, we assessed the effects of fingolimod on WM microstructure, cognition and symptoms in an eight-week, double-blind trial. Forty subjects with schizophrenia or schizoaffective disorder were randomized 1:1 to fingolimod (0.5 mg/day) and placebo. Fingolimod caused significant reductions in circulating lymphocytes (p < .001). In addition, there was a statistically non-significant association (p = .089) between DTI-FA change in the WM skeleton and fingolimod. There were significant relationships between the degree of lymphocyte reductions and increases in FA in the corpus collosum (p = .004) and right superior longitudinal fasciculus ( p = .02), and a non-significant correlation with the WM skeleton. There were no significant fingolimod versus placebo interactions on cognitive or symptom measures. There were no serious adverse events related to fingolimod treatment. Future studies with larger samples and treatment durations are needed to further establish fingolimod's potential therapeutic effects in schizophrenia.


Assuntos
Esquizofrenia , Substância Branca , Anisotropia , Encéfalo/diagnóstico por imagem , Cognição , Imagem de Tensor de Difusão , Cloridrato de Fingolimode/uso terapêutico , Humanos , Lisofosfolipídeos , Imageamento por Ressonância Magnética , Projetos Piloto , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Esfingosina/análogos & derivados , Substância Branca/diagnóstico por imagem
15.
Brain Imaging Behav ; 14(5): 1921-1932, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31197580

RESUMO

Negative urgency, defined as a tendency to act rashly under extreme negative emotion, is strongly associated with tobacco use. Despite the robust evidence linking negative urgency and tobacco use and accumulating evidence suggesting that localized, segregated brain regions such as the nucleus accumbens (NAcc), insula, and amygdala are related to negative urgency, resting state functional connectivity (rsFC) of negative urgency in tobacco use has not yet been examined. This study included 34 daily tobacco users and 62 non-users matched on age, gender, race/ethnicity, and lifetime psychiatric diagnosis from a publicly available neuroimaging dataset collected by the Nathan Kline Institute-Rockland Project. Using the bilateral NAcc, insula, and amygdala as seed regions, seed-based rsFC analyses were conducted on the whole brain. In the whole sample, negative urgency was positively correlated with rsFC between the left insula and right dorsal anterior cingulate cortex (dACC). Compared to non-users, tobacco users had a stronger rsFC strength between the right amygdala and right middle temporal gyrus. In tobacco users, negative urgency was negatively associated with rsFC between the left NAcc and right dACC and between the left NAcc and right dorsolateral prefrontal cortex; these relationships were positive in non-users. Identifying functional connectivity implicated in negative urgency and tobacco use is the crucial first step to design and test pharmacological and physiological interventions to reduce negative urgency related tobacco use.


Assuntos
Córtex Cerebral/fisiopatologia , Corpo Estriado/fisiopatologia , Giro do Cíngulo/fisiopatologia , Descanso , Uso de Tabaco/fisiopatologia , Adulto , Feminino , Humanos , Masculino
16.
Schizophr Res ; 218: 107-115, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32037204

RESUMO

Schizophrenia is a disorder of altered neural connections resulting in impaired information integration. Whole brain assessment of within- and between-network connections may determine how information processing is disrupted in schizophrenia. Patients with early-stage schizophrenia (n = 56) and a matched control sample (n = 32) underwent resting-state fMRI scans. Gray matter regions were organized into nine distinct functional networks. Functional connectivity was calculated between 278 gray matter regions for each subject. Network connectivity properties were defined by the mean and variance of correlations of all regions. Whole-brain network measures of global efficiency (reflecting overall interconnectedness) and locations of hubs (key regions for communication) were also determined. The control sample had greater connectivity between the following network pairs: somatomotor-limbic, somatomotor-default mode, dorsal attention-default mode, ventral attention-limbic, and ventral attention-default mode. The patient sample had greater variance in interactions between ventral attention network and other functional networks. Illness duration was associated with overall increases in the variability of network connections. The control group had higher global efficiency and more hubs in the cerebellum network, while patient group hubs were more common in visual, frontoparietal, or subcortical networks. Thus, reduced functional connectivity in patients was largely present between distinct networks, rather than within-networks. The implications of these findings for the pathophysiology of schizophrenia are discussed.


Assuntos
Mapeamento Encefálico , Esquizofrenia , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem
17.
Artigo em Inglês | MEDLINE | ID: mdl-32007432

RESUMO

BACKGROUND: Suicidality is a leading cause of death among adolescents. In addition to other psychiatric conditions, youths with attention-deficit/hyperactivity disorder (ADHD) and disruptive behavior disorders (DBDs) are at heightened risk for suicide. Decision-making deficits are a hallmark symptom of ADHD and DBDs and are also implicated in suicidal behavior. We examined behavioral and neural differences in decision making among youths with ADHD and DBDs with (SI+) and without (SI-) histories of suicidal ideation. METHODS: The Balloon Analog Risk Task, a risky decision-making task, was completed by 57 youths with ADHD and DBDs (38% SI+) during functional magnetic resonance imaging. Mean stop wager (mean wager at which youths bank money) was the primary measure of risk taking. We conducted whole-brain and region-of-interest analyses in the anterior cingulate cortex and orbitofrontal cortex (OFC) during choice (win vs. inflate) and outcome (inflate vs. explode) contrasts using parametric modulators accounting for probability of balloon explosion. RESULTS: There were no differences between SI+ and SI- youths in Balloon Analog Risk Task performance. SI+ youths showed decreasing activation in the right medial frontal gyrus when choosing inflate as explosion probability increased compared with SI- youths. During explosions, SI- youths showed increasing activation in the left OFC as explosions became more likely. SI+ showed increasing left medial OFC activity in response to inflations as explosion probability increased. CONCLUSIONS: SI+ youths may show heightened sensitivity to immediate reward and decreased sensitivity to potential loss as evidenced by medial frontal gyrus activity. OFC findings suggest that SI+ youths may be drawn to reward even when there is high probability of loss.


Assuntos
Comportamento Problema , Ideação Suicida , Adolescente , Tomada de Decisões , Humanos , Imageamento por Ressonância Magnética , Recompensa
18.
Horm Behav ; 55(4): 548-59, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19470369

RESUMO

The putative human pheromone Delta4,16-androstadien-3-one (androstadienone), a non-androgenic steroid found in sweat and saliva, modulates psychological, physiological and hormonal responses without detection as an odor. To determine the specific psychological processes altered by androstadienone, four studies were completed by 50 men and women after solutions of 250 microM androstadienone or clove-odor control carrier, on separate days, were applied to their upper lip: (1) face pairs were subliminally presented, with one face neutral and the other happy or angry. Androstadienone accelerated speed to locate a subsequent dot probe appearing on the same side as emotional faces, without affecting overall reaction times, indicating that androstadienone specifically enhanced automatic attention to emotional information. (2) In two Stroop paradigms, emotional or mismatched color words interfered with ink color identification. Androstadienone slowed ink color identification of emotional words, demonstrating greater allocation of attentional resources towards emotional information, with no effect on the cognitive Stroop. (3) To test effects on social cognition, participants performed two working memory tasks with distinct stimuli, neutral faces or shapes. Androstadienone did not alter attention to either the social or nonsocial images. (4) The ameliorative effects of androstadienone on self-reported attentiveness were replicated, consistent with increased attention to emotional visual stimuli. Moreover, androstadienone did not alter positive or negative mood, as participants were alone during testing, which removed emotional stimuli from social interactions with a tester. Taken together, these findings demonstrate that subliminal androstadienone guides psychological resources to specifically engage stimuli with emotional significance and does not alter attention to social or general cognitive information.


Assuntos
Androstadienos/metabolismo , Emoções/fisiologia , Feromônios Humano/metabolismo , Adolescente , Adulto , Afeto/fisiologia , Atenção/fisiologia , Cognição/fisiologia , Face , Expressão Facial , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Leitura , Caracteres Sexuais , Percepção Social , Estimulação Subliminar , Percepção Visual/fisiologia , Adulto Jovem
19.
Dev Cogn Neurosci ; 36: 100634, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30889545

RESUMO

OBJECTIVE: Risk-taking during adolescence is a leading cause of mortality; Neuroscience research examining pubertal effects on decision-making is needed to better inform interventions, particularly among youth with attention-deficit/hyperactivity (ADHD) and disruptive behavior disorders (DBD), who are particularly prone to risky decision-making. We examined effects of pubertal development on risky decision-making and neural activation during decision-making among youth with ADHD/DBDs. METHOD: Forty-six 11-12-year-olds (29.4% girls; 54.9% white; Tanner M(SD) = 2.08(1.32)) who met DSM-5 criteria for ADHD/DBD completed the Balloon Analog Risk Task (BART) during fMRI scanning. We examined effects of Tanner stage, sex, and age on risky decision-making (mean wager at which individuals stopped balloon inflation) and neural activation in the middle frontal gyrus and the ventral striatum during the choice and outcome phases of decision-making. RESULTS: Those in earlier pubertal stages made riskier decisions during the BART compared to those in later Tanner stages (ß=-0.62, p = .02). Later pubertal stage was associated with greater activation in the left middle frontal gyrus (ß=0.61, p = .03) during the choice phase and in the right ventral striatum in response to rewards (ß=0.59, p = .03). CONCLUSION: Youth with ADHD/DBD in later stages of puberty, regardless of age, show greater ventral striatal activation in response to rewards.


Assuntos
Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Tomada de Decisões/fisiologia , Imageamento por Ressonância Magnética/métodos , Maturidade Sexual/fisiologia , Criança , Feminino , Humanos , Masculino , Assunção de Riscos
20.
Brain Imaging Behav ; 13(3): 852-861, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29855992

RESUMO

Cognitive dysfunction is a core facet of schizophrenia that is present early in the course of the illness and contributes to diminished functioning and outcomes. Repetitive transcranial magnetic stimulation (rTMS) is a relatively new neuropsychiatric intervention. Initially used in treatment resistant depression, investigators are now studying rTMS for other psychiatric diseases such as schizophrenia. In this study we examined the effect of high frequency rTMS on cognitive function in a group of individuals with early phase psychosis. Twenty subjects were randomized (1:1) in double-blind fashion to rTMS or sham condition. Over two weeks subjects underwent ten sessions of high frequency, bilateral, sequential rTMS targeting the dorsolateral prefrontal cortex (DLPFC). Prior to beginning and following completion of study treatment, subjects completed a cognitive assessment and magnetic resonance imaging. Subjects receiving rTMS, compared to sham treatment, displayed improvement on a standardized cognitive battery both immediately following the course of study treatment and at follow-up two weeks later. Imaging results revealed that left frontal cortical thickness at baseline was correlated with treatment response. The study treatment was found to be safe and well tolerated. These results suggest that rTMS may hold promise for the treatment of cognitive dysfunction in the early phase of psychosis, and that MRI may provide biomarkers predicting response to the treatment.


Assuntos
Cognição/fisiologia , Esquizofrenia/terapia , Estimulação Magnética Transcraniana/métodos , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Projetos Piloto , Córtex Pré-Frontal/fisiopatologia , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/terapia , Esquizofrenia/fisiopatologia , Resultado do Tratamento , Adulto Jovem
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