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1.
Medicine (Baltimore) ; 100(4): e24319, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33530222

RESUMO

RATIONALE: Several brain structures, including the orbital prefrontal cortex, ventrolateral prefrontal cortex, dorsolateral prefrontal cortex, amygdala, and anterior cingulate cortex, are considered key structures in the neural circuitry underlying emotion regulation. We report on a patient showing behavior changes and degeneration of core neural tracts for emotional regulation following traumatic brain injury (TBI). PATIENT CONCERNS: A 51-year-old male patient suffered an in-car accident. The patient lost consciousness for approximately 30 days, and his Glasgow Coma Scale score was 3. He underwent stereotactic drainage for traumatic intraventricular and intracerebral hemorrhages. At approximately 6.5-year after onset, he began to show disinhibition behaviors such as shouting with anger, which worsened over time. At approximately 8-year after onset, he showed severe depression signs and disinhibition, including violence. DIAGNOSES: The patient who showed delayed-onset behavioral changes (disinhibition and depression). INTERVENTIONS: Diffusion tensor imaging data were acquired at 3 months and 8 years after TBI onset. OUTCOMES: The patient showed degeneration of core neural tracts for emotional regulation that was associated with delayed behavioral changes following TBI. On both 3-month and 8-year diffusion tensor tractographies (DTTs), the right dorsolateral prefronto-thalamic tract, ventrolateral prefronto-thalamic tract, orbital prefronto-thalamic tract, uncinate fasciculus, and both cinguli were reconstructed whereas other neural tracts were not reconstructed. Compared with the 3-month DTT, all reconstructed neural tracts on the 8-year DTT were narrow, except for the left cingulum, which showed new transcallosal fibers between both anterior cingula. The fractional anisotropy and tract volume of all reconstructed neural tracts were lower on the 8-year DTT than the 3-month DTT, except for the tract volume of left cingulum. LESSONS: The evaluation of dorsolateral, ventrolateral, and orbital prefronto-thalamic tract, uncinate fasciculus, and cingulum using follow-up DTTs is useful when a patient with TBI shows delayed-onset behavioral problems.


Assuntos
Lesões Encefálicas Traumáticas/psicologia , Regulação Emocional , Degeneração Neural/psicologia , Acidentes de Trânsito , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Depressão/diagnóstico por imagem , Depressão/etiologia , Imagem de Tensor de Difusão , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/lesões , Humanos , Inibição Psicológica , Masculino , Pessoa de Meia-Idade , Degeneração Neural/diagnóstico por imagem , Degeneração Neural/etiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/lesões , Técnicas de Rastreamento Neuroanatômico , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/lesões , Tálamo/diagnóstico por imagem , Tálamo/lesões , /lesões
2.
Nat Commun ; 12(1): 904, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568654

RESUMO

In a dynamic world, it is essential to decide when to leave an exploited resource. Such patch-leaving decisions involve balancing the cost of moving against the gain expected from the alternative patch. This contrasts with value-guided decisions that typically involve maximizing reward by selecting the current best option. Patterns of neuronal activity pertaining to patch-leaving decisions have been reported in dorsal anterior cingulate cortex (dACC), whereas competition via mutual inhibition in ventromedial prefrontal cortex (vmPFC) is thought to underlie value-guided choice. Here, we show that the balance between cortical excitation and inhibition (E/I balance), measured by the ratio of GABA and glutamate concentrations, plays a dissociable role for the two kinds of decisions. Patch-leaving decision behaviour relates to E/I balance in dACC. In contrast, value-guided decision-making relates to E/I balance in vmPFC. These results support mechanistic accounts of value-guided choice and provide evidence for a role of dACC E/I balance in patch-leaving decisions.


Assuntos
Tomada de Decisões , Giro do Cíngulo/fisiologia , Adulto , Excitabilidade Cortical , Feminino , Ácido Glutâmico/análise , Ácido Glutâmico/metabolismo , Giro do Cíngulo/química , Giro do Cíngulo/diagnóstico por imagem , Humanos , Masculino , Inibição Neural , Córtex Pré-Frontal , Adulto Jovem , Ácido gama-Aminobutírico/análise , Ácido gama-Aminobutírico/metabolismo
3.
Nord J Psychiatry ; 75(3): 224-233, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33411645

RESUMO

OBJECTIVE: Arterial spin labeling (ASL) is a relatively new imaging modality in the field of the cognitive neuroscience. In the present study, we aimed to compare the dynamic regional cerebral blood flow alterations of children with ADHD and healthy controls during a neurocognitive task by using event-related ASL scanning. METHODS: The study comprised of 17 healthy controls and 20 children with ADHD. The study subjects were scanned on 3 Tesla MRI scanner to obtain ASL imaging data. Subjects performed go/no-go task during the ASL image acquisition. The image analyses were performed by FEAT (fMRI Expert Analysis Tool) Version 6. RESULTS: The mean age was 10.88 ± 1.45 and 11 ± 1.91 for the control and ADHD group, respectively (p = .112). The go/no-go task was utilized during the ASL scanning. The right anterior cingulate cortex (BA32) extending into the frontopolar and orbitofrontal cortices (BA10 and 11) displayed greater activation in ADHD children relative to the control counterparts (p < .001). With a lenient significance threshold, greater activation was revealed in the right-sided frontoparietal regions during the go session, and in the left precuneus during the no-go session. CONCLUSION: These results indicate that children with ADHD needed to over-activate frontopolar cortex, anterior cingulate as well as the dorsal and ventral attention networks to compensate for the attention demanded in a given cognitive task.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Giro do Cíngulo , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Mapeamento Encefálico , Córtex Cerebral , Circulação Cerebrovascular , Criança , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Testes Neuropsicológicos , Córtex Pré-Frontal/diagnóstico por imagem
4.
Ideggyogy Sz ; 73(9-10): 303-308, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33035419

RESUMO

Evidence suggests that pathogen-associated pattern recognition receptors (Toll-like receptors, TLRs) are implicated in the pathophysiology of schizophrenia. TLRs are important in both peripheral immune responses and neuronal plasticity. However, the relationship between peripheral TLR expression and regional brain volumes is unknown in schizophrenia. We therefore assessed 30 drug-naïve, first-episode patients with schizophrenia. TLR4+/TLR1+ monocytes were measured using flow-cytometry. High resolution magnetic resonance images (T1 MRI) were obtained and analyzed with FreeSurfer. Results revealed significant negative correlations between the percentage of TLR4+ monocytes, mean fluorescent intensities, and brain volumes in frontal and anterior cingulate regions. The measures of TLR1+ monocytes did not show significant relationships with regional brain volumes. These results raise the possibility that abnormal TLR-activation is associated with decreased brain volumes in schizophrenia.


Assuntos
Lobo Frontal/metabolismo , Imagem por Ressonância Magnética/métodos , Esquizofrenia/genética , Esquizofrenia/metabolismo , Receptor 4 Toll-Like/metabolismo , Antipsicóticos/uso terapêutico , Lobo Frontal/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/metabolismo , Humanos , Polimorfismo de Nucleotídeo Único , Esquizofrenia/tratamento farmacológico
5.
Nat Commun ; 11(1): 5386, 2020 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-33106488

RESUMO

Stress-related disorders such as depression and anxiety are characterized by enhanced negative emotion and physiological dysfunction. Whilst elevated activity within area 25 of the subgenual anterior cingulate cortex (sgACC/25) has been implicated in these illnesses, it is unknown whether this over-activity is causal. By combining targeted intracerebral microinfusions with cardiovascular and behavioral monitoring in marmosets, we show that over-activation of sgACC/25 reduces vagal tone and heart rate variability, alters cortisol dynamics during stress and heightens reactivity to proximal and distal threat. 18F-FDG PET imaging shows these changes are accompanied by altered activity within a network of brain regions including the amygdala, hypothalamus and dorsolateral prefrontal cortex. Ketamine, shown to have rapid antidepressant effects, fails to reverse elevated arousal to distal threat contrary to the beneficial effects we have previously demonstrated on over-activation induced reward blunting, illustrating the symptom-specificity of its actions.


Assuntos
Vias Autônomas/fisiologia , Callithrix/psicologia , Fenômenos Fisiológicos Cardiovasculares , Giro do Cíngulo/fisiologia , Animais , Nível de Alerta , Comportamento Animal , Callithrix/fisiologia , Medo , Feminino , Giro do Cíngulo/diagnóstico por imagem , Frequência Cardíaca , Hidrocortisona/metabolismo , Masculino , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons
6.
PLoS One ; 15(8): e0236521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756593

RESUMO

OBJECTIVES: The study aimed at determining the EEG correlates of concentration on either low or high-distressed tinnitus. METHODS: Sixty-seven patients (36 women, mean age = 50.34 ± 12.94 years) with chronic tinnitus were assigned to either a high (HD) or low (LD) tinnitus-related distress group based on THI results. All participants took part in the EEG study comprising two 3-4 min blocks of focusing on either tinnitus (Tinnitus Focus Condition, TFC) or the sensations from one's own body (Body Focus Condition, BFC). The absolute power and current density of 8 frequency bands in 7 clusters were compared between conditions and groups. RESULTS: The most pronounced differences were found in the HD patients in the TFC, relative to the BFC, i.e. reduced power of frontally distributed low alpha (8-10 Hz) and posterior high alpha (10-12 Hz) as well as lower current density of 8-10 Hz rhythm over the right frontal/anterior cingulate cortex and higher middle beta (15-18 Hz) density in the precuneus. The HD, relative to LD patients, in both conditions, exhibited increased low beta (12-15 Hz) power over the left middle area and greater higher beta (15-25 Hz) power in the left posterior region. CONCLUSIONS: The present study contrasted bioelectrical activity, acquired when concentrating on tinnitus with EEG data collected whilst patients focused on their body. Decreased alpha power and current density in the frontal/cingulate cortex when listening to bothersome tinnitus might reflect greater cortical arousal whereas increased beta power and density in the precuneus/posterior cingulate activity in this condition could be indicative for elevated tension or augmented cognitive/emotional processing of tinnitus sound. Enhanced beta rhythm in patients with high versus low tinnitus distress, observed independently of the study condition, may be due to greater self-focused attention or more active processing of sensations derived from the own body.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Encéfalo/fisiopatologia , Zumbido/fisiopatologia , Adulto , Nível de Alerta/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Eletroencefalografia , Emoções/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Zumbido/complicações , Zumbido/diagnóstico por imagem
7.
Am J Psychiatry ; 177(10): 965-973, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32660299

RESUMO

OBJECTIVE: Low-dose testosterone has been shown to improve depression symptom severity, fatigue, and sexual function in small studies in women not formally diagnosed with major depressive disorder. The authors sought to determine whether adjunctive low-dose transdermal testosterone improves depression symptom severity, fatigue, and sexual function in women with antidepressant-resistant major depression. A functional MRI (fMRI) substudy examined effects on activity in the anterior cingulate cortex (ACC), a brain region important in mood regulation. METHODS: The authors conducted an 8-week randomized double-blind placebo-controlled trial of adjunctive testosterone cream in 101 women, ages 21-70, with antidepressant-resistant major depression. The primary outcome measure was depression symptom severity as assessed by the Montgomery-Åsberg Depression Rating Scale (MADRS). Secondary endpoints included fatigue, sexual function, and safety measures. The primary outcome of the fMRI substudy (N=20) was change in ACC activity. RESULTS: The participants' mean age was 47 years (SD=14) and their mean baseline MADRS score was 26.6 (SD=5.9). Eighty-seven (86%) participants completed 8 weeks of treatment. MADRS scores decreased in both study arms from baseline to week 8 (testosterone arm: from 26.8 [SD=6.3] to 15.3 [SD=9.6]; placebo arm: from 26.3 [SD=5.4] to 14.4 [SD=9.3]), with no significant difference between groups. Improvement in fatigue and sexual function did not differ between groups, nor did side effects. fMRI results showed a relationship between ACC activation and androgen levels before treatment but no difference in ACC activation with testosterone compared with placebo. CONCLUSIONS: Adjunctive transdermal testosterone, although well tolerated, was not more effective than placebo in improving symptoms of depression, fatigue, or sexual dysfunction. Imaging in a subset of participants demonstrated that testosterone did not result in greater activation of the ACC.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Testosterona/uso terapêutico , Adulto , Idoso , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Resistente a Tratamento/diagnóstico por imagem , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Neuroimagem Funcional , Giro do Cíngulo/diagnóstico por imagem , Humanos , Hidrocortisona/sangue , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Creme para a Pele , Testosterona/administração & dosagem , Testosterona/sangue , Adulto Jovem
8.
Psychiatry Res Neuroimaging ; 301: 111103, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32464339

RESUMO

Bipolar disorder (BD) has been associated with impaired executive functioning and integrity of fronto-limbic white matter tracts. The evaluation of these factors in young offspring of patients with BD (BDoff) as a high-risk group offers an opportunity to investigate factors that could predict vulnerability to the disorder. This study aims to examine the correlation between neurocognition and neuroimaging findings to evaluate the potential for these findings as biomarkers for the early recognition of BD. We enrolled BDoff (n = 16) who were aged between 12 and 18. Participants were assessed using clinical and neurocognitive tests. In addition, structural brain magnetic resonance and diffusion tensor imaging data were obtained. Mean fractional anisotropy (FA) and mean diffusivity (MD) values of the superior longitudinal fasciculus (SLF) and cingulum were extracted and correlations with neuropsychological data were analyzed. FA values in the SLF were negatively correlated with Stroop interference, the Wisconsin Card Sorting Test, and the Trail Making Test (B-A) scores. MD values in the cingulum were inversely correlated with the Child and Youth Resilience Measure and positively correlated with higher scores on the Barratt Impulsiveness Scale-Attentional. These findings provide a link between features of the brain and cognitive dysfunction in BDoff.


Assuntos
Transtorno Bipolar , Filho de Pais Incapacitados/psicologia , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Adolescente , Anisotropia , Criança , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Estudos Transversais , Função Executiva/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/patologia , Humanos , Comportamento Impulsivo/fisiologia , Masculino , Testes de Estado Mental e Demência , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Resiliência Psicológica , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
9.
Psychiatry Res Neuroimaging ; 301: 111102, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32447185

RESUMO

To reconcile the inconsistency of the association between the resting-state functional connectivity (RSFC) and cognitive performance in healthy and depressed groups due to high variance of both measures, we proposed a Bayesian spatio-temporal model to precisely and accurately estimate the RSFC in depressed and nondepressed participants. This model was employed to estimate spatially-adjusted functional connectivity (saFC) in the extended default mode network (DMN) that was hypothesized to correlate with cognitive performance in both depressed and nondepressed. Multiple linear regression models were used to study the relationship between DMN saFC and cognitive performance scores measured in the following four cognitive domains while adjusting for age, sex, and education. In ROI pairs including the posterior cingulate (PCC) and anterior cingulate (ACC) cortex regions, the relationship between connectivity and cognition was found only with the Bayesian approach. Moreover, only the Bayesian approach was able to detect a significant diagnostic difference in the association in ROI pairs, including both PCC and ACC regions, due to smaller variance for the saFC estimator. The results confirm that a reliable and precise saFC estimator, based on the Bayesian model, can foster scientific discovery that may not be feasible with the conventional ROI-based FC estimator (denoted as 'AVG-FC').


Assuntos
Cognição , Transtorno Depressivo Maior/fisiopatologia , Neuroimagem Funcional/métodos , Imagem por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Adulto , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Análise Espaço-Temporal , Análise e Desempenho de Tarefas , Adulto Jovem
10.
Proc Natl Acad Sci U S A ; 117(18): 10015-10023, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32312809

RESUMO

Chronic pain is a highly prevalent disease with poorly understood pathophysiology. In particular, the brain mechanisms mediating the transition from acute to chronic pain remain largely unknown. Here, we identify a subcortical signature of back pain. Specifically, subacute back pain patients who are at risk for developing chronic pain exhibit a smaller nucleus accumbens volume, which persists in the chronic phase, compared to healthy controls. The smaller accumbens volume was also observed in a separate cohort of chronic low-back pain patients and was associated with dynamic changes in functional connectivity. At baseline, subacute back pain patients showed altered local nucleus accumbens connectivity between putative shell and core, irrespective of the risk of transition to chronic pain. At follow-up, connectivity changes were observed between nucleus accumbens and rostral anterior cingulate cortex in the patients with persistent pain. Analysis of the power spectral density of nucleus accumbens resting-state activity in the subacute and chronic back pain patients revealed loss of power in the slow-5 frequency band (0.01 to 0.027 Hz) which developed only in the chronic phase of pain. This loss of power was reproducible across two cohorts of chronic low-back pain patients obtained from different sites and accurately classified chronic low-back pain patients in two additional independent datasets. Our results provide evidence that lower nucleus accumbens volume confers risk for developing chronic pain and altered nucleus accumbens activity is a signature of the state of chronic pain.


Assuntos
Dor nas Costas/fisiopatologia , Dor Crônica/fisiopatologia , Giro do Cíngulo/fisiopatologia , Núcleo Accumbens/fisiopatologia , Adulto , Dor nas Costas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Dor Crônica/diagnóstico por imagem , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Rede Nervosa/fisiopatologia , Vias Neurais/fisiopatologia , Núcleo Accumbens/diagnóstico por imagem , Fatores de Risco
11.
PLoS One ; 15(4): e0230837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271789

RESUMO

Interrogation elicits anxiety in individuals under scrutiny regardless of their innocence, and thus, anxious responses to interrogation should be differentiated from deceptive behavior in practical lie detection settings. Despite its importance, not many empirical studies have yet been done to separate the effects of interrogation from the acts of lying or guilt state. The present fMRI study attempted to identify neural substrates of anxious responses under interrogation in either innocent or guilt contexts by developing a modified "Doubt" game. Participants in the guilt condition showed higher brain activations in the right central-executive network and bilateral basal ganglia. Regardless of the person's innocence, we observed higher activation of the salience, theory of mind and sensory-motor networks-areas associated with anxiety-related responses in the interrogative condition, compared to the waived conditions. We further explored two different types of anxious responses under interrogation-true detection anxiety in the guilty (true positive) and false detection anxiety in the innocent (false positive). Differential neural responses across these two conditions were captured at the caudate, thalamus, ventral anterior cingulate and ventromedial prefrontal cortex. We conclude that anxiety is a common neural response to interrogation, regardless of an individual's innocence, and that there are detectable differences in neural responses for true positive and false positive anxious responses under interrogation. The results of our study highlight a need to isolate complex cognitive processes involved in the deceptive acts from the emotional and regulatory responses to interrogation in lie detection schemes.


Assuntos
Ansiedade , Encéfalo/diagnóstico por imagem , Culpa , Detecção de Mentiras/psicologia , Adulto , Análise de Variância , Ansiedade/psicologia , Encéfalo/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiologia , Humanos , Aplicação da Lei , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia
12.
Psychiatry Res Neuroimaging ; 300: 111079, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283474

RESUMO

Heart rate variability (HRV), a measurement of autonomic nervous system (ANS) activity, has been found reduced in schizophrenia. The anterior cingulate cortex (ACC), which is important in regulating the ANS, is structurally and functionally affected in schizophrenia. We investigate the relationship between HRV and functional and structural connectivity of the ACC in patients with schizophrenia and healthy controls. Ten patients with a diagnosis of schizophrenia and ten healthy controls were recruited. Heart rate was monitored in a naturalistic out-of-clinic setting. Magnetic resonance imaging (MRI) was performed, including resting-state functional MRI and diffusion tensor imaging. Patients with schizophrenia had significantly lower HRV compared to controls. A positive correlation between ACC connectivity with the bilateral cerebellum and HRV was found in the patients. HRV was also positively correlated with amplitude of low frequency fluctuations (ALFF) in the cerebellum, and with axial diffusivity in the middle cerebellar peduncle, in the patients. There was a significant negative relationship between antipsychotic medication dosage, HRV and all neuroimaging measures related to HRV. We conclude that ACC connectivity seems to be affected in schizophrenia, both structurally and functionally, and that the ACC-cerebellum connectivity, as well as cerebellar function, is associated with ANS regulation in patients with schizophrenia.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Frequência Cardíaca/fisiologia , Rede Nervosa/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Antipsicóticos/uso terapêutico , Sistema Nervoso Autônomo/diagnóstico por imagem , Estudos de Casos e Controles , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico
13.
J Neurosci ; 40(16): 3268-3277, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32156831

RESUMO

Adaptive coding of stimuli is well documented in perception, where it supports efficient encoding over a broad range of possible percepts. Recently, a similar neural mechanism has been reported also in value-based decision, where it allows optimal encoding of vast ranges of values in PFC: neuronal response to value depends on the choice context (relative coding), rather than being invariant across contexts (absolute coding). Additionally, value learning is sensitive to the amount of feedback information: providing complete feedback (both obtained and forgone outcomes) instead of partial feedback (only obtained outcome) improves learning. However, it is unclear whether relative coding occurs in all PFC regions and how it is affected by feedback information. We systematically investigated univariate and multivariate feedback encoding in various mPFC regions and compared three modes of neural coding: absolute, partially-adaptive and fully-adaptive.Twenty-eight human participants (both sexes) performed a learning task while undergoing fMRI scanning. On each trial, they chose between two symbols associated with a certain outcome. Then, the decision outcome was revealed. Notably, in one-half of the trials participants received partial feedback, whereas in the other half they got complete feedback. We used univariate and multivariate analysis to explore value encoding in different feedback conditions.We found that both obtained and forgone outcomes were encoded in mPFC, but with opposite sign in its ventral and dorsal subdivisions. Moreover, we showed that increasing feedback information induced a switch from absolute to relative coding. Our results suggest that complete feedback information enhances context-dependent outcome encoding.SIGNIFICANCE STATEMENT This study offers a systematic investigation of the effect of the amount of feedback information (partial vs complete) on univariate and multivariate outcome value encoding, within multiple regions in mPFC and cingulate cortex that are critical for value-based decisions and behavioral adaptation. Moreover, we provide the first comparison of three possible models of neural coding (i.e., absolute, partially-adaptive, and fully-adaptive coding) of value signal in these regions, by using commensurable measures of prediction accuracy. Taken together, our results help build a more comprehensive picture of how the human brain encodes and processes outcome value. In particular, our results suggest that simultaneous presentation of obtained and foregone outcomes promotes relative value representation.


Assuntos
Tomada de Decisões/fisiologia , Retroalimentação Psicológica/fisiologia , Giro do Cíngulo/diagnóstico por imagem , Aprendizagem/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Adulto , Feminino , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Reforço Psicológico , Adulto Jovem
14.
Phys Ther ; 100(6): 946-962, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32201890

RESUMO

BACKGROUND: Pain is one of the main symptoms associated with spinal cord injury (SCI) and can be associated with changes to the central nervous system (CNS). PURPOSE: This article provides an overview of the evidence relating to CNS changes (structural and functional) associated with pain in SCIs. DATA SOURCES: A systematic review was performed, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, on PubMed, Embase, and Web of Science in March 2018. STUDY SELECTION: Studies were selected if they concerned changes in the CNS of patients with SCI, regardless of the type of imagery. DATA EXTRACTION: Data were extracted by 2 blinded reviewers. DATA SYNTHESIS: There is moderate evidence for impaired electroencephalographic function and metabolic abnormalities in the anterior cingulate in patients experiencing pain. There is preliminary evidence that patients with pain have morphological and functional changes to the somatosensory cortex and alterations to thalamic metabolism. There are conflicting data regarding the relationships between lesion characteristics and pain. In contrast, patients without pain can display protective neuroplasticity. LIMITATIONS AND CONCLUSION: Further studies are required to elucidate fully the relationships between pain and neuroplasticity in patients with SCIs. However, current evidence might support the use of physical therapist treatments targeting CNS plasticity in patients with SCI pain.


Assuntos
Sistema Nervoso Central/patologia , Sistema Nervoso Central/fisiopatologia , Dor Crônica/etiologia , Neuralgia/etiologia , Traumatismos da Medula Espinal/complicações , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Sistema Nervoso Central/diagnóstico por imagem , Sistema Nervoso Central/metabolismo , Dor Crônica/fisiopatologia , Eletroencefalografia/métodos , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imagem por Ressonância Magnética/métodos , Neuralgia/fisiopatologia , Neuroimagem/métodos , Plasticidade Neuronal/fisiologia , Viés de Seleção , Córtex Somatossensorial/diagnóstico por imagem , Córtex Somatossensorial/patologia , Córtex Somatossensorial/fisiopatologia , Medula Espinal/diagnóstico por imagem , Medula Espinal/metabolismo , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , Tálamo/diagnóstico por imagem , Tálamo/metabolismo
15.
PLoS One ; 15(2): e0228866, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32069310

RESUMO

Episodic memory is the ability to learn, store and recall new information. The prefrontal cortex (PFC) is a crucial area engaged in this ability. Cognitive training has been demonstrated to improve episodic memory in adults and older subjects. However, there are no studies examining the effects of cognitive training on episodic memory encoding in typically developing children and adolescents. This study investigated the behavioral effects and neural correlates of semantic categorization strategy training in children and adolescents during verbal episodic memory encoding using functional magnetic resonance imaging (fMRI). Participants with age range: 7-18 years were scanned before and after semantic categorization training during encoding of word lists. Results showed improved memory performance in adolescents, but not in children. Deactivation of the anterior medial PFC/anterior cingulate and higher activation of the right anterior and lateral orbital gyri, right frontal pole and right middle frontal gyrus activation were found after training in adolescents when compared to children. These findings suggest different maturational paths of brain regions, especially in the PFC, and deactivation of default mode network areas, which are involved in successful memory and executive processes in the developing brain.


Assuntos
Memória Episódica , Semântica , Adolescente , Desenvolvimento do Adolescente/fisiologia , Mapeamento Encefálico , Criança , Desenvolvimento Infantil/fisiologia , Cognição/fisiologia , Feminino , Neuroimagem Funcional , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/crescimento & desenvolvimento , Giro do Cíngulo/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/crescimento & desenvolvimento , Córtex Pré-Frontal/fisiologia
16.
Neurourol Urodyn ; 39(3): 969-977, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32032447

RESUMO

AIMS: We compared brain activation patterns between female multiple sclerosis (MS) patients with voiding dysfunction (VD) and those without. We aim to expand current knowledge of supraspinal correlates of voiding initiation within a cohort of female MS patients with and without VD. MATERIALS AND METHODS: Twenty-eight ambulatory female MS patients with stable disease and lower urinary tract dysfunction were recruited for this study. Subjects were divided into group 1, without VD (n = 14), and group 2, with VD (n = 14), defined as postvoid residual urine of ≥40% of maximum cystometric capacity or need for self-catheterization. We recorded brain activity via functional magnetic resonance imaging (fMRI) with simultaneous urodynamic testing. Average fMRI activation maps (the Student t test) were created for both groups, and areas of significant activation were identified (P < .05). A priori regions of interest (ROIs), identified by prior meta-analysis to be involved in voiding, were selected. RESULTS: Group-averaged blood-oxygen level-dependent (BOLD) activation maps demonstrated significant differences between groups 1 and 2 during initiation of voiding with group 2 showing significantly lower levels of activation in all ROIs except for the left cerebellum and right cingulate gyrus. Interestingly, group 2 displayed negative BOLD signals, while group 1 displayed positive signals in the right and left pontine micturition center, right periaqueductal gray, left thalamus, and left cingulate gyrus. The activation map of group 1 was similar to healthy controls. CONCLUSIONS: Our results support the hypothesis that distinct supraspinal activation patterns exist between female MS patients with VD and those without.


Assuntos
Encéfalo/diagnóstico por imagem , Sintomas do Trato Urinário Inferior/fisiopatologia , Esclerose Múltipla/diagnóstico por imagem , Bexiga Urinaria Neurogênica/fisiopatologia , Transtornos Urinários/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Feminino , Neuroimagem Funcional , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Sintomas do Trato Urinário Inferior/etiologia , Imagem por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/fisiopatologia , Substância Cinzenta Periaquedutal/diagnóstico por imagem , Substância Cinzenta Periaquedutal/fisiopatologia , Ponte/diagnóstico por imagem , Ponte/fisiopatologia , Tálamo/diagnóstico por imagem , Tálamo/fisiopatologia , Bexiga Urinária/fisiopatologia , Bexiga Urinaria Neurogênica/etiologia , Micção/fisiologia , Transtornos Urinários/etiologia , Urodinâmica/fisiologia
17.
Nat Hum Behav ; 4(4): 412-422, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31932692

RESUMO

Activity in the dorsal anterior cingulate cortex (dACC) is observed across a variety of contexts, and its function remains intensely debated in the field of cognitive neuroscience. While traditional views emphasize its role in inhibitory control (suppressing prepotent, incorrect actions), recent proposals suggest a more active role in motivated control (invigorating actions to obtain rewards). Lagging behind empirical findings, formal models of dACC function primarily focus on inhibitory control, highlighting surprise, choice difficulty and value of control as key computations. Although successful in explaining dACC involvement in inhibitory control, it remains unclear whether these mechanisms generalize to motivated control. In this study, we derive predictions from three prominent accounts of dACC and test these with functional magnetic resonance imaging during value-based decision-making under time pressure. We find that the single mechanism of surprise best accounts for activity in dACC during a task requiring response invigoration, suggesting surprise signalling as a shared driver of inhibitory and motivated control.


Assuntos
Tomada de Decisões/fisiologia , Giro do Cíngulo/fisiologia , Adulto , Antecipação Psicológica/fisiologia , Feminino , Neuroimagem Funcional , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Modelos Neurológicos , Tempo de Reação , Recompensa , Adulto Jovem
18.
Brain Cogn ; 139: 105518, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31954233

RESUMO

Excessive video gaming has a number of psychological and social consequences. In this study, we looked at possible changes in gray and white matter and asked whether these changes are correlated to psychological measures. Twentynine players of violent videogames (mean daily playing time 4.7 h) and age matched controls were subjected to a battery of questionnaires assessing aggression, empathy, hostility, internet addiction and psychological well-being. Diffusion tensor and 3D T1-weighted MR images were obtained to examine gray (via voxel-based morphometry) and white (via tract-based spatial statistics) matter changes. Widespread regions of decreased gray matter in the players were found but no region showed increased intensity of gray matter. Density of gray matter showed a negative correlation with the total length of playing in years in the right posterior cingulate gyrus, left pre- and postcentral gyrus, right thalamus, among others. Furthermore, fractional anisotropy, a marker for white matter structure, was decreased in the left and right cingulum in the players. Both, gray and white matter changes correlated with measures of aggression, hostility, self esteem, and the degree of internet addiction. This study thus shows profound changes of brain structure as a function of excessive playing of violent video games.


Assuntos
Comportamento Aditivo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Internet , Jogos de Vídeo , Adolescente , Adulto , Anisotropia , Comportamento Aditivo/psicologia , Encéfalo/patologia , Estudos de Casos e Controles , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/patologia , Humanos , Imagem por Ressonância Magnética , Masculino , Tamanho do Órgão , Autoimagem , Córtex Somatossensorial/diagnóstico por imagem , Córtex Somatossensorial/patologia , Tálamo/diagnóstico por imagem , Tálamo/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Adulto Jovem
19.
Brain Cogn ; 139: 105517, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31945602

RESUMO

Transcendental Meditation (TM) is defined as a mental process of transcending using a silent mantra. Previous work showed that relatively brief period of TM practice leads to decreases in stress and anxiety. However, whether these changes are subserved by specific morpho-functional brain modifications (as observed in other meditation techniques) is still unclear. Using a longitudinal design, we combined psychometric questionnaires, structural and resting-state functional magnetic resonance imaging (RS-fMRI) to investigate the potential brain modifications underlying the psychological effects of TM. The final sample included 19 naïve subjects instructed to complete two daily 20-min TM sessions, and 15 volunteers in the control group. Both groups were evaluated at recruitment (T0) and after 3 months (T1). At T1, only meditators showed a decrease in perceived anxiety and stress (t(18) = 2.53, p = 0.02), which correlated negatively with T1-T0 changes in functional connectivity among posterior cingulate cortex (PCC), precuneus and left superior parietal lobule. Additionally, TM practice was associated with increased connectivity between PCC and right insula, likely reflecting changes in interoceptive awareness. No structural changes were observed in meditators or control subjects. These preliminary findings indicate that beneficial effects of TM may be mediated by functional brain changes that take place after a short practice period of 3 months.


Assuntos
Ansiedade/terapia , Encéfalo/diagnóstico por imagem , Meditação/métodos , Estresse Psicológico/terapia , Adulto , Ansiedade/diagnóstico por imagem , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Feminino , Neuroimagem Funcional , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Parietal/diagnóstico por imagem , Psicometria , Estresse Psicológico/diagnóstico por imagem , Inquéritos e Questionários , Adulto Jovem
20.
Nat Commun ; 11(1): 246, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937764

RESUMO

Synaptic dysfunction is hypothesised to play a key role in schizophrenia pathogenesis, but this has not been tested directly in vivo.  Here, we investigated synaptic vesicle glycoprotein 2A (SV2A) levels and their relationship to symptoms and structural brain measures using [11C]UCB-J positron emission tomography in 18 patients with schizophrenia and 18 controls. We found significant group and group-by-region interaction effects on volume of distribution (VT). [11C]UCB-J VT was significantly lower in the frontal and anterior cingulate cortices in schizophrenia with large effect sizes (Cohen's d = 0.8-0.9), but there was no significant difference in the hippocampus. We also investigated the effects of antipsychotic drug administration on SV2A levels in Sprague-Dawley rats using western blotting, [3H]UCB-J autoradiography and immunostaining with confocal microscopy, finding no significant effects on any measure. These findings indicate that there are lower synaptic terminal protein levels in schizophrenia in vivo and that antipsychotic drug exposure is unlikely to account for them.


Assuntos
Antipsicóticos/uso terapêutico , Encéfalo/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/metabolismo , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/metabolismo , Humanos , Masculino , Especificidade de Órgãos , Tomografia por Emissão de Pósitrons , Piridinas/metabolismo , Pirrolidinonas/metabolismo , Ratos , Ratos Sprague-Dawley , Esquizofrenia/diagnóstico por imagem
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