Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Psychol Med ; 53(7): 2831-2841, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34852855

RESUMO

BACKGROUND: Overgeneralised self-blame and worthlessness are key symptoms of major depressive disorder (MDD) and have previously been associated with self-blame-selective changes in connectivity between right superior anterior temporal lobe (rSATL) and subgenual frontal cortices. Another study showed that remitted MDD patients were able to modulate this neural signature using functional magnetic resonance imaging (fMRI) neurofeedback training, thereby increasing their self-esteem. The feasibility and potential of using this approach in symptomatic MDD were unknown. METHOD: This single-blind pre-registered randomised controlled pilot trial probed a novel self-guided psychological intervention with and without additional rSATL-posterior subgenual cortex (BA25) fMRI neurofeedback, targeting self-blaming emotions in people with insufficiently recovered MDD and early treatment-resistance (n = 43, n = 35 completers). Participants completed three weekly self-guided sessions to rebalance self-blaming biases. RESULTS: As predicted, neurofeedback led to a training-induced reduction in rSATL-BA25 connectivity for self-blame v. other-blame. Both interventions were safe and resulted in a 46% reduction on the Beck Depression Inventory-II, our primary outcome, with no group differences. Secondary analyses, however, revealed that patients without DSM-5-defined anxious distress showed a superior response to neurofeedback compared with the psychological intervention, and the opposite pattern in anxious MDD. As predicted, symptom remission was associated with increases in self-esteem and this correlated with the frequency with which participants employed the psychological strategies in daily life. CONCLUSIONS: These findings suggest that self-blame-rebalance neurofeedback may be superior over a solely psychological intervention in non-anxious MDD, although further confirmatory studies are needed. Simple self-guided strategies tackling self-blame were beneficial, but need to be compared against treatment-as-usual in further trials. https://doi.org/10.1186/ISRCTN10526888.


Assuntos
Transtorno Depressivo Maior , Neurorretroalimentação , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/terapia , Transtorno Depressivo Maior/patologia , Projetos Piloto , Neurorretroalimentação/métodos , Depressão , Imageamento por Ressonância Magnética , Método Simples-Cego
2.
Neuroimage ; 249: 118863, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34974116

RESUMO

TMS has become a powerful tool to explore cortical function, and in parallel has proven promising in the development of therapies for various psychiatric and neurological disorders. Unfortunately, much of the inference of the direct effects of TMS has been assumed to be limited to the area a few centimeters beneath the scalp, though clearly more distant regions are likely to be influenced by structurally connected stimulation sites. In this study, we sought to develop a novel paradigm to individualize TMS coil placement to non-invasively achieve activation of specific deep brain targets of relevance to the treatment of psychiatric disorders. In ten subjects, structural diffusion imaging tractography data were used to identify an accessible cortical target in the right frontal pole that demonstrated both anatomic and functional connectivity to right Brodmann area 25 (BA25). Concurrent TMS-fMRI interleaving was used with a series of single, interleaved TMS pulses applied to the right frontal pole at four intensity levels ranging from 80% to 140% of motor threshold. In nine of ten subjects, TMS to the individualized frontal pole sites resulted in significant linear increase in BOLD activation of BA25 with increasing TMS intensity. The reliable activation of BA25 in a dosage-dependent manner suggests the possibility that the careful combination of imaging with TMS can make use of network properties to help overcome depth limitations and allow noninvasive brain stimulation to influence deep brain structures.


Assuntos
Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Estimulação Encefálica Profunda , Imagem de Tensor de Difusão , Estimulação Magnética Transcraniana , Adulto , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
3.
Neuromodulation ; 25(2): 202-210, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35125139

RESUMO

OBJECTIVES: Despite converging basic scientific and clinical evidence of the link between chronic pain and depression, existing therapies do not often take advantage of this overlap. Here, we provide a critical review of the literature that highlights the intersection in brain networks between chronic low back pain (CLBP) and depression and discuss findings from previous deep brain stimulation (DBS) studies for pain. Based on a multidimensional model of pain processing and the connectivity of the subgenual cingulate cortex (SCC) with areas that are implicated in both CLBP and depression, we propose a novel approach to the treatment of CLBP using DBS of the SCC. MATERIALS AND METHODS: A narrative review with literature assessment. RESULTS: CLBP is associated with a shift away from somatosensory representation toward brain regions that mediate emotional processes. There is a high degree of overlap between these regions and those involved in depression, including the anterior cingulate cortex, medial prefrontal cortex, nucleus accumbens, and amygdala. Whereas target sites from previous DBS trials for pain were not anatomically positioned to engage these areas and their associated networks, the SCC is structurally connected to all of these regions as well as others involved in mediating sensory, cognitive, and affective processing in CLBP. CONCLUSIONS: CLBP and depression share a common underlying brain network interconnected by the SCC. Current data and novel technology provide an optimal opportunity to develop clinically effective trials of SCC DBS for CLBP.


Assuntos
Dor Crônica , Estimulação Encefálica Profunda , Dor Lombar , Encéfalo , Mapeamento Encefálico , Dor Crônica/terapia , Giro do Cíngulo/diagnóstico por imagem , Humanos , Dor Lombar/diagnóstico por imagem , Dor Lombar/terapia
4.
J Neurosci ; 37(42): 10215-10229, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-28924006

RESUMO

Important real-world decisions are often arduous as they frequently involve sequences of choices, with initial selections affecting future options. Evaluating every possible combination of choices is computationally intractable, particularly for longer multistep decisions. Therefore, humans frequently use heuristics to reduce the complexity of decisions. We recently used a goal-directed planning task to demonstrate the profound behavioral influence and ubiquity of one such shortcut, namely aversive pruning, a reflexive Pavlovian process that involves neglecting parts of the decision space residing beyond salient negative outcomes. However, how the brain implements this important decision heuristic and what underlies individual differences have hitherto remained unanswered. Therefore, we administered an adapted version of the same planning task to healthy male and female volunteers undergoing functional magnetic resonance imaging (fMRI) to determine the neural basis of aversive pruning. Through both computational and standard categorical fMRI analyses, we show that when planning was influenced by aversive pruning, the subgenual cingulate cortex was robustly recruited. This neural signature was distinct from those associated with general planning and valuation, two fundamental cognitive components elicited by our task but which are complementary to aversive pruning. Furthermore, we found that individual variation in levels of aversive pruning was associated with the responses of insula and dorsolateral prefrontal cortices to the receipt of large monetary losses, and also with subclinical levels of anxiety. In summary, our data reveal the neural signatures of an important reflexive Pavlovian process that shapes goal-directed evaluations and thereby determines the outcome of high-level sequential cognitive processes.SIGNIFICANCE STATEMENT Multistep decisions are complex because initial choices constrain future options. Evaluating every path for long decision sequences is often impractical; thus, cognitive shortcuts are often essential. One pervasive and powerful heuristic is aversive pruning, in which potential decision-making avenues are curtailed at immediate negative outcomes. We used neuroimaging to examine how humans implement such pruning. We found it to be associated with activity in the subgenual cingulate cortex, with neural signatures that were distinguishable from those covarying with planning and valuation. Individual variations in aversive pruning levels related to subclinical anxiety levels and insular cortex activation. These findings reveal the neural mechanisms by which basic negative Pavlovian influences guide decision-making during planning, with implications for disrupted decision-making in psychiatric disorders.


Assuntos
Aprendizagem da Esquiva/fisiologia , Comportamento de Escolha/fisiologia , Condicionamento Clássico/fisiologia , Tomada de Decisões/fisiologia , Objetivos , Giro do Cíngulo/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
5.
Neuroimage ; 88: 252-62, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24121201

RESUMO

Blocking of the serotonin transporter (SERT) represents the initial mechanism of action of selective serotonin reuptake inhibitors (SSRIs) which can be visualized due to the technical proceedings of SERT occupancy studies. When compared to the striatum, higher SERT occupancy in the midbrain and lower values in the thalamus were reported. This indicates that occupancy might be differently distributed throughout the brain, which is supported by preclinical findings indicating a regionally varying SERT activity and antidepressant drug concentration. The present study therefore aimed to investigate regional SERT occupancies with positron emission tomography and the radioligand [(11)C]DASB in 19 depressed patients after acute and prolonged intake of oral doses of either 10mg/day escitalopram or 20mg/day citalopram. Compared to the mean occupancy across cortical and subcortical regions, we detected increased SERT occupancies in regions commonly associated with antidepressant response, such as the subgenual cingulate, amygdala and raphe nuclei. When acute and prolonged drug intake was compared, SERT occupancies increased in subcortical areas that are known to be rich in SERT. Moreover, SERT occupancy in subcortical brain areas after prolonged intake of antidepressants was predicted by plasma drug levels. Similarly, baseline SERT binding potential seems to impact SERT occupancy, as regions rich in SERT showed greater binding reduction as well as higher residual binding. These findings suggest a region-specific distribution of SERT blockage by SSRIs and relate the postulated link between treatment response and SERT occupancy to certain brain regions such as the subgenual cingulate cortex.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/sangue
6.
Front Neurosci ; 16: 779964, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281511

RESUMO

Listening to samba percussion often elicits feelings of pleasure and the desire to move with the beat-an experience sometimes referred to as "feeling the groove"- as well as social connectedness. Here we investigated the effects of performance timing in a Brazilian samba percussion ensemble on listeners' experienced pleasantness and the desire to move/dance in a behavioral experiment, as well as on neural processing as assessed via functional magnetic resonance imaging (fMRI). Participants listened to different excerpts of samba percussion produced by multiple instruments that either were "in sync", with no additional asynchrony between instrumental parts other than what is usual in naturalistic recordings, or were presented "out of sync" by delaying the snare drums (by 28, 55, or 83 ms). Results of the behavioral experiment showed increasing pleasantness and desire to move/dance with increasing synchrony between instruments. Analysis of hemodynamic responses revealed stronger bilateral brain activity in the supplementary motor area, the left premotor area, and the left middle frontal gyrus with increasing synchrony between instruments. Listening to "in sync" percussion thus strengthens audio-motor interactions by recruiting motor-related brain areas involved in rhythm processing and beat perception to a higher degree. Such motor related activity may form the basis for "feeling the groove" and the associated desire to move to music. Furthermore, in an exploratory analysis we found that participants who reported stronger emotional responses to samba percussion in everyday life showed higher activity in the subgenual cingulate cortex, an area involved in prosocial emotions, social group identification and social bonding.

7.
Biol Psychiatry ; 90(10): 689-700, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32800379

RESUMO

Transcranial magnetic stimulation (TMS) is an effective treatment for depression but is limited in that the optimal therapeutic target remains unknown. Early TMS trials lacked a focal target and thus positioned the TMS coil over the prefrontal cortex using scalp measurements. Over time, it became clear that this method leads to variation in the stimulation site and that this could contribute to heterogeneity in antidepressant response. Newer methods allow for precise positioning of the TMS coil over a specific brain location, but leveraging these precise methods requires a more precise therapeutic target. We review how neuroimaging is being used to identify a more focal therapeutic target for depression. We highlight recent studies showing that more effective TMS targets in the frontal cortex are functionally connected to deep limbic regions such as the subgenual cingulate cortex. We review how connectivity might be used to identify an optimal TMS target for use in all patients and potentially even a personalized target for each individual patient. We address the clinical implications of this emerging field and highlight critical questions for future research.


Assuntos
Transtorno Depressivo Maior , Estimulação Magnética Transcraniana , Encéfalo/diagnóstico por imagem , Depressão/terapia , Humanos , Neuroimagem
8.
Eur Psychiatry ; 63(1): e37, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32284075

RESUMO

BACKGROUND: Aberrant activity of the subcallosal cingulate (SCC) is a common theme across pharmacologic treatment efficacy prediction studies. The functioning of the SCC in psychotherapeutic interventions is relatively understudied, as are functional differences among SCC subdivisions. We conducted functional connectivity analyses (rsFC) on resting-state functional magnetic resonance imaging (fMRI) data, collected before and after a course of cognitive behavioral therapy (CBT) in patients with major depressive disorder (MDD), using seeds from three SCC subdivisions. METHODS: Resting-state data were collected from unmedicated patients with current MDD (Hamilton Depression Rating Scale-17 > 16) before and after 14-sessions of CBT monotherapy. Treatment outcome was assessed using the Beck Depression Inventory (BDI). Rostral anterior cingulate (rACC), anterior subcallosal cingulate (aSCC), and Brodmann's area 25 (BA25) masks were used as seeds in connectivity analyses that assessed baseline rsFC and symptom severity, changes in connectivity related to symptom improvement after CBT, and prediction of treatment outcomes using whole-brain baseline connectivity. RESULTS: Pretreatment BDI negatively correlated with pretreatment rACC ~ dorsolateral prefrontal cortex and aSCC ~ lateral prefrontal cortex rsFC. In a region-of-interest longitudinal analysis, rsFC between these regions increased post-treatment (p < 0.05FDR). In whole-brain analyses, BA25 ~ paracentral lobule and rACC ~ paracentral lobule connectivities decreased post-treatment. Whole-brain baseline rsFC with SCC did not predict clinical improvement. CONCLUSIONS: rsFC features of rACC and aSCC, but not BA25, correlated inversely with baseline depression severity, and increased following CBT. Subdivisions of SCC involved in top-down emotion regulation may be more involved in cognitive interventions, while BA25 may be more informative for interventions targeting bottom-up processing. Results emphasize the importance of subdividing the SCC in connectivity analyses.


Assuntos
Terapia Cognitivo-Comportamental , Conectoma , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/terapia , Giro do Cíngulo/fisiopatologia , Imageamento por Ressonância Magnética , Resultado do Tratamento , Adulto , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
9.
Neurosci Biobehav Rev ; 108: 207-217, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31733222

RESUMO

Moral motivations drive humans to sacrifice selfish needs to serve the needs of others and internalized sociocultural norms. Over the past two decades, several brain regions have been associated with different aspects of moral cognition and behaviour. Only more recently, however, investigations have highlighted the importance of the basal forebrain for moral motivation. This includes the septo-hypothalamic region, implicated in kinship bonding across mammal species, and the closely connected subgenual frontal cortex. Understanding the neuroanatomy of moral motivation and its impairments will be fundamental for future research aiming to promote prosocial behaviour and mental health.


Assuntos
Prosencéfalo Basal/fisiologia , Giro do Cíngulo/fisiologia , Hipotálamo/fisiologia , Princípios Morais , Motivação/fisiologia , Apego ao Objeto , Cognição Social , Humanos
10.
Soc Cogn Affect Neurosci ; 14(8): 815-826, 2019 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-31506680

RESUMO

Depression has been reliably associated with abnormalities in the neural representation of reward and loss. However, most studies have focused on monetary incentives; fewer studies have considered neural representation of social incentives. A direct comparison of non-social and social incentives within the same study would establish whether responses to the different incentives are differentially affected in depression. The functional magnetic resonance imaging study presented here investigated the neural activity of individuals with subthreshold depression (SD) and healthy controls (HCs) while they participated in an incentive delay task offering two types of reward (monetary gain vs social approval) and loss (monetary loss vs social disapproval). Compared to HCs, individuals with SD showed increased subgenual anterior cingulate cortex (sgACC) activity during anticipation of social loss, whereas the response in the putamen was decreased during consumption of social gain. Individuals with SD also exhibited diminished insula responses in consuming social loss. Furthermore, positive connectivity between the insula and ventral lateral pre-frontal cortex (VLPFC) was observed in individuals with SD while negative connectivity was found in HCs when consuming social loss. These results demonstrate neural alterations in individuals with depression, specific to the processing of social incentives, mainly characterised by dysfunction within the 'social pain network' (sgACC, insula and VLPFC).


Assuntos
Antecipação Psicológica/fisiologia , Depressão/fisiopatologia , Depressão/psicologia , Motivação/fisiologia , Adulto , Córtex Cerebral/fisiopatologia , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Putamen/fisiopatologia , Recompensa , Comportamento Social , Adulto Jovem
11.
Handb Clin Neurol ; 166: 317-326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31731919

RESUMO

Anterior midcingulate cortex (aMCC) has been shown to be involved in most of the functional imaging studies investigating acute pain. For 10-15 years, it has even been a main focus of interest for pain studies, considering that neurons in the aMCC could encode for pain intensity. This latter function is now presumed to occur in secondary somatosensory (SII) area and/or insular cortices, while anterior cingulate cortex (ACC) is supposed to sustain other functions such as pain-related attention, arousal, motor withdrawal reflex, pain modulations, and engagement of endogenous pain control system. The quantitative imaging studies have shown a rich density of opioid receptors in the ACC. Thus, the perigenual subdivision has been suggested to participate in top-down controls of pain, (including the placebo effects known to be opioid mediated), mainly (but not exclusively) through the connection between the orbitofrontal/subgenual ACC and the periaqueductal gray (PAG). From this rationale, this area may lead to neurosurgical targeting including electrical stimulation for intractable pain in the future. A number of imaging studies have also reported activity changes in the posterior cingulate cortex during pain and proposed its speculative involvement to modulate the conscious experience of pain according to elements from the context and awareness of the self and others.


Assuntos
Dor Crônica/fisiopatologia , Giro do Cíngulo/fisiopatologia , Animais , Dor Crônica/terapia , Estimulação Elétrica , Humanos , Manejo da Dor/métodos
12.
Neuroimage Clin ; 24: 101992, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31505367

RESUMO

Previously, using fMRI, we demonstrated lower connectivity between right anterior superior temporal (ATL) and anterior subgenual cingulate (SCC) regions while patients with major depressive disorder (MDD) experience guilt. This neural signature was detected despite symptomatic remission which suggested a putative role in vulnerability. This randomised controlled double-blind parallel group clinical trial investigated whether patients with MDD are able to voluntarily modulate this neural signature. To this end, we developed a fMRI neurofeedback software (FRIEND), which measures ATL-SCC coupling and displays its levels in real time. Twenty-eight patients with remitted MDD were randomised to two groups, each receiving one session of fMRI neurofeedback whilst retrieving guilt and indignation/anger-related autobiographical memories. They were instructed to feel the emotion whilst trying to increase the level of a thermometer-like display on a screen. Active intervention group: The thermometer levels increased with increasing levels of ATL-SCC correlations in the guilt condition. Control intervention group: The thermometer levels decreased when correlation levels deviated from the previous baseline level in the guilt condition, thus reinforcing stable correlations. Both groups also received feedback during the indignation condition reinforcing stable correlations. We confirmed our predictions that patients in the active intervention group were indeed able to increase levels of ATL-SCC correlations for guilt vs. indignation and their self-esteem after training compared to before training and that this differed significantly from the control intervention group. These data provide proof-of-concept for a novel treatment target for MDD patients and are in keeping with the hypothesis that ATL-SCC connectivity plays a key role in self-worth. https://clinicaltrials.gov/ct2/show/results/NCT01920490.


Assuntos
Transtorno Depressivo Maior/fisiopatologia , Neuroimagem Funcional , Culpa , Giro do Cíngulo/fisiopatologia , Neurorretroalimentação/fisiologia , Autoimagem , Lobo Temporal/fisiopatologia , Adulto , Transtorno Depressivo Maior/diagnóstico por imagem , Método Duplo-Cego , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Lobo Temporal/diagnóstico por imagem
13.
Biol Psychiatry ; 83(1): 81-89, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28935211

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a debilitating mental illness and a major cause of lost productivity worldwide. MDD patients often suffer from lifelong recurring episodes of increasing severity, reduced therapeutic response, and shorter remission periods, suggesting the presence of a persistent and potentially progressive pathology. METHODS: Subgenual anterior cingulate cortex postmortem samples from four MDD cohorts (single episode, n = 20; single episode in remission, n = 15; recurrent episode, n = 20; and recurrent episode in remission, n = 15), and one control cohort (n = 20) were analyzed by mass spectrometry-based proteomics (n = 3630 proteins) combined with statistical analyses. The data was investigated for trait and state progressive neuropathologies in MDD using both unbiased approaches and tests of a priori hypotheses. RESULTS: The data provided weak evidence for proteomic differences as a function of state (depressed/remitted) or number of previous episodes. Instead it suggested the presence of persistent MDD effects, regardless of episodes or remitted state, namely on proteomic measures related to presynaptic neurotransmission, synaptic function, cytoskeletal rearrangements, energy metabolism, phospholipid biosynthesis/metabolism, and calcium ion homeostasis. Selected proteins (dihydropyrimidinase-related protein 1, synaptosomal-associated protein 29, glutamate decarboxylase 1, metabotropic glutamate receptor 1, and excitatory amino acid transporter 3) were validated by Western blot analysis. The findings were independent of technical, demographic (sex or age), or other clinical parameters (death by suicide and drug treatment). CONCLUSIONS: Collectively, the results provide evidence for persistent MDD effects across current episodes or remission, in the absence of detectable progressive neuropathology.


Assuntos
Transtorno Depressivo Maior/metabolismo , Giro do Cíngulo/metabolismo , Proteoma , Adulto , Western Blotting , Cromatografia Líquida , Estudos de Coortes , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/patologia , Progressão da Doença , Feminino , Giro do Cíngulo/patologia , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Proteômica
14.
Soc Cogn Affect Neurosci ; 10(7): 961-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25416726

RESUMO

Changes in the functional connectivity of the subgenual anterior cingulate cortex (SGC) have been linked with depressive symptoms. The aim of this study was to map this relationship across mid to late adolescence. Employing a longitudinal functional magnetic resonance imaging (fMRI) design, associations between patterns of resting-state SGC functional connectivity and symptoms of depression were examined at two time points in an initial sample of 72 adolescents. Using a region-of-interest approach, these associations were evaluated cross-sectionally and longitudinally. Cross-sectionally, weaker SGC functional connectivity with the posterior cingulate cortex (PCC), angular gyrus and dorsal prefrontal cortex at baseline, and weaker SGC connectivity with the dorsomedial prefrontal cortex (DMPFC) and ventromedial prefrontal cortex at follow-up, were associated with higher depressive symptoms. Longitudinally, a decrease in SGC functional connectivity with DMPFC, PCC, angular gyrus and middle temporal gyrus was associated with higher depressive symptoms at follow-up. The observation of weaker SGC connectivity predicting increased symptoms contrasts with the majority of resting-state fMRI studies in clinically depressed populations. Taken together with these past studies, our findings suggest depression-related changes in SGC functional connectivity may differ across developmental and illness stages.


Assuntos
Mapeamento Encefálico , Depressão/patologia , Giro do Cíngulo/patologia , Vias Neurais/patologia , Adolescente , Anatomia Transversal , Progressão da Doença , Feminino , Lateralidade Funcional , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/patologia
15.
Neuroimage Clin ; 8: 1-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26110109

RESUMO

Functional, molecular and genetic neuroimaging has highlighted the existence of brain anomalies and neural vulnerability factors related to obesity and eating disorders such as binge eating or anorexia nervosa. In particular, decreased basal metabolism in the prefrontal cortex and striatum as well as dopaminergic alterations have been described in obese subjects, in parallel with increased activation of reward brain areas in response to palatable food cues. Elevated reward region responsivity may trigger food craving and predict future weight gain. This opens the way to prevention studies using functional and molecular neuroimaging to perform early diagnostics and to phenotype subjects at risk by exploring different neurobehavioral dimensions of the food choices and motivation processes. In the first part of this review, advantages and limitations of neuroimaging techniques, such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), pharmacogenetic fMRI and functional near-infrared spectroscopy (fNIRS) will be discussed in the context of recent work dealing with eating behavior, with a particular focus on obesity. In the second part of the review, non-invasive strategies to modulate food-related brain processes and functions will be presented. At the leading edge of non-invasive brain-based technologies is real-time fMRI (rtfMRI) neurofeedback, which is a powerful tool to better understand the complexity of human brain-behavior relationships. rtfMRI, alone or when combined with other techniques and tools such as EEG and cognitive therapy, could be used to alter neural plasticity and learned behavior to optimize and/or restore healthy cognition and eating behavior. Other promising non-invasive neuromodulation approaches being explored are repetitive transcranial magnetic stimulation (rTMS) and transcranial direct-current stimulation (tDCS). Converging evidence points at the value of these non-invasive neuromodulation strategies to study basic mechanisms underlying eating behavior and to treat its disorders. Both of these approaches will be compared in light of recent work in this field, while addressing technical and practical questions. The third part of this review will be dedicated to invasive neuromodulation strategies, such as vagus nerve stimulation (VNS) and deep brain stimulation (DBS). In combination with neuroimaging approaches, these techniques are promising experimental tools to unravel the intricate relationships between homeostatic and hedonic brain circuits. Their potential as additional therapeutic tools to combat pharmacorefractory morbid obesity or acute eating disorders will be discussed, in terms of technical challenges, applicability and ethics. In a general discussion, we will put the brain at the core of fundamental research, prevention and therapy in the context of obesity and eating disorders. First, we will discuss the possibility to identify new biological markers of brain functions. Second, we will highlight the potential of neuroimaging and neuromodulation in individualized medicine. Third, we will introduce the ethical questions that are concomitant to the emergence of new neuromodulation therapies.


Assuntos
Encéfalo/fisiopatologia , Terapia por Estimulação Elétrica/métodos , Eletroencefalografia/métodos , Comportamento Alimentar/fisiologia , Transtornos da Alimentação e da Ingestão de Alimentos , Neurorretroalimentação/métodos , Neuroimagem/métodos , Obesidade , Estimulação Magnética Transcraniana/métodos , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Transtornos da Alimentação e da Ingestão de Alimentos/prevenção & controle , Transtornos da Alimentação e da Ingestão de Alimentos/terapia , Humanos , Obesidade/fisiopatologia , Obesidade/prevenção & controle , Obesidade/terapia
16.
Soc Neurosci ; 9(4): 326-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24802255

RESUMO

Attachment to one's kin as an in-group emerges from a fundamental human motivation and is vital for human survival. Despite important recent advances in the field of social neuroscience, the neural mechanisms underlying family-related in-group perception remain obscure. To examine the neural basis of perceiving family-related in-group boundaries in response to written kinship scenarios, we used functional magnetic resonance imaging in 27 healthy adults and obtained self-report ratings of family-related entitativity, which measures to what degree participants perceive their family as a coherent and distinct group in society. We expected that activity in the subgenual cingulate cortex and septo-hypothalamic region would track individual differences in entitativity. Perceiving one's family as a distinct and cohesive group (high entitativity) was associated with increased subgenual cortex response to kinship scenarios. The subgenual cingulate cortex may represent a key link between kin-related emotional attachment and group perception, providing a neurobiological basis for group belongingness.


Assuntos
Família/psicologia , Processos Grupais , Giro do Cíngulo/fisiologia , Pensamento/fisiologia , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Percepção/fisiologia , Autorrelato
17.
J Neurosurg ; 121(5): 1219-31, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25170668

RESUMO

Traumatic brain injury (TBI) remains a significant public health problem and is a leading cause of death and disability in many countries. Durable treatments for neurological function deficits following TBI have been elusive, as there are currently no FDA-approved therapeutic modalities for mitigating the consequences of TBI. Neurostimulation strategies using various forms of electrical stimulation have recently been applied to treat functional deficits in animal models and clinical stroke trials. The results from these studies suggest that neurostimulation may augment improvements in both motor and cognitive deficits after brain injury. Several studies have taken this approach in animal models of TBI, showing both behavioral enhancement and biological evidence of recovery. There have been only a few studies using deep brain stimulation (DBS) in human TBI patients, and future studies are warranted to validate the feasibility of this technique in the clinical treatment of TBI. In this review, the authors summarize insights from studies employing neurostimulation techniques in the setting of brain injury. Moreover, they relate these findings to the future prospect of using DBS to ameliorate motor and cognitive deficits following TBI.


Assuntos
Lesões Encefálicas/terapia , Terapia por Estimulação Elétrica/métodos , Animais , Lesões Encefálicas/psicologia , Estimulação Encefálica Profunda , Humanos , Recuperação de Função Fisiológica , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA