Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
Mais filtros

País/Região como assunto
Intervalo de ano de publicação
1.
Psychol Med ; 53(12): 5488-5499, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36043367

RESUMO

BACKGROUND: Repetitive negative thinking (RNT), a cognitive process that encompasses past (rumination) and future (worry) directed thoughts focusing on negative experiences and the self, is a transdiagnostic construct that is especially relevant for major depressive disorder (MDD). Severe RNT often occurs in individuals with severe levels of MDD, which makes it challenging to disambiguate the neural circuitry underlying RNT from depression severity. METHODS: We used a propensity score, i.e., a conditional probability of having high RNT given observed covariates to match high and low RNT individuals who are similar in the severity of depression, anxiety, and demographic characteristics. Of 148 MDD individuals, we matched high and low RNT groups (n = 50/group) and used a data-driven whole-brain voxel-to-voxel connectivity pattern analysis to investigate the resting-state functional connectivity differences between the groups. RESULTS: There was an association between RNT and connectivity in the bilateral superior temporal sulcus (STS), an important region for speech processing including inner speech. High relative to low RNT individuals showed greater connectivity between right STS and bilateral anterior insular cortex (AI), and between bilateral STS and left dorsolateral prefrontal cortex (DLPFC). Greater connectivity in those regions was specifically related to RNT but not to depression severity. CONCLUSIONS: RNT intensity is directly related to connectivity between STS and AI/DLPFC. This might be a mechanism underlying the role of RNT in perceptive, cognitive, speech, and emotional processing. Future investigations will need to determine whether modifying these connectivities could be a treatment target to reduce RNT.


Assuntos
Transtorno Depressivo Maior , Regulação Emocional , Pessimismo , Humanos , Transtorno Depressivo Maior/psicologia , Depressão/psicologia , Pessimismo/psicologia , Semântica , Inquéritos e Questionários , Ansiedade/psicologia
2.
Psychother Psychosom ; 92(2): 87-100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36630946

RESUMO

INTRODUCTION: Repetitive negative thinking (RNT) is a cognitive process focusing on self-relevant and negative experiences, leading to a poor prognosis of major depressive disorder (MDD). We previously identified that connectivity between the precuneus/posterior cingulate cortex (PCC) and right temporoparietal junction (rTPJ) was positively correlated with levels of RNT. OBJECTIVE: In this double-blind, randomized, sham-controlled, proof-of-concept trial, we employed real-time functional magnetic resonance imaging neurofeedback (rtfMRI-nf) to delineate the neural processes that may be causally linked to RNT and could potentially become treatment targets for MDD. METHODS: MDD-affected individuals were assigned to either active (n = 20) or sham feedback group (n = 19). RNT was measured by the Ruminative Response Scale-brooding subscale (RRS-B) before and 1 week after the intervention. RESULTS: Individuals in the active but not in the sham group showed a significant reduction in the RRS-B; however, a greater reduction in the PCC-rTPJ connectivity was unrelated to a greater reduction in the RRS-B. Exploratory analyses revealed that a greater reduction in the retrosplenial cortex (RSC)-rTPJ connectivity yielded a more pronounced reduction in the RRS-B in the active but not in the sham group. CONCLUSIONS: RtfMRI-nf was effective in reducing RNT. Considering the underlying mechanism of rtfMIR-nf, the RSC and rTPJ could be part of a network (i.e., default mode network) that might collectively affect the intensity of RNT. Understanding the relationship between the functional organization of targeted neural changes and clinical metrics, such as RNT, has the potential to guide the development of mechanism-based treatment of MDD.


Assuntos
Transtorno Depressivo Maior , Neurorretroalimentação , Pessimismo , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/terapia , Neurorretroalimentação/métodos , Depressão , Imageamento por Ressonância Magnética/métodos
3.
Dev World Bioeth ; 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37436004

RESUMO

As neuroethics continues to grow as an established discipline, it has been charged with not being sufficiently sensitive to the way in which the identification, conceptualization, and management of the ethical issues raised by neuroscience and its applications are shaped by local systems of knowledge and structures. Recently there have been calls for explicit recognition of the role played by local cultural contexts and for the development of cross-cultural methodologies that can facilitate meaningful cultural engagement. In this article, we attempt to fill this perceived gap by providing a culturally situated analysis of the practice of electroconvulsive therapy (ECT) in Argentina. ECT was introduced as a psychiatric treatment in Argentina in the 1930s but it is largely underutilized. While the use of ECT remains low in several countries, what makes the Argentinian case interesting is that the executive branch of government has taken a stance regarding both the scientific and moral appropriateness of ECT, recommending its prohibition. Here, we begin with a recent controversy over the use of ECT in Argentina and explain the legal recommendation to ban its application. Next, we offer an overview of some of the salient aspect of the international and local discussions on ECT. We argue that the governmental recommendation to ban the procedure should be rethought. While acknowledging the role that contexts and local conditions play in shaping the identification and assessment of the relevant ethical issues, we caution against using contextual and cultural considerations to avoid a necessary ethical debate on controversial issues.

4.
Psychol Med ; 52(11): 2177-2188, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34158132

RESUMO

BACKGROUND: Cognition heavily relies on social determinants and genetic background. Latin America comprises approximately 8% of the global population and faces unique challenges, many derived from specific demographic and socioeconomic variables, such as violence and inequality. While such factors have been described to influence mental health outcomes, no large-scale studies with Latin American population have been carried out. Therefore, we aim to describe the cognitive performance of a representative sample of Latin American individuals with schizophrenia and its relationship to clinical factors. Additionally, we aim to investigate how socioeconomic status (SES) relates to cognitive performance in patients and controls. METHODS: We included 1175 participants from five Latin American countries (Argentina, Brazil, Chile, Colombia, and Mexico): 864 individuals with schizophrenia and 311 unaffected subjects. All participants were part of projects that included cognitive evaluation with MATRICS Consensus Cognitive Battery and clinical assessments. RESULTS: Patients showed worse cognitive performance than controls across all domains. Age and diagnosis were independent predictors, indicating similar trajectories of cognitive aging for both patients and controls. The SES factors of education, parental education, and income were more related to cognition in patients than in controls. Cognition was also influenced by symptomatology. CONCLUSIONS: Patients did not show evidence of accelerated cognitive aging; however, they were most impacted by a lower SES suggestive of deprived environment than controls. These findings highlight the vulnerability of cognitive capacity in individuals with psychosis in face of demographic and socioeconomic factors in low- and middle-income countries.


Assuntos
Esquizofrenia , Humanos , América Latina/epidemiologia , Esquizofrenia/epidemiologia , Esquizofrenia/diagnóstico , Classe Social , Fatores Socioeconômicos , Cognição
5.
Br J Psychiatry ; 218(2): 112-118, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32807243

RESUMO

BACKGROUND: Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear. AIMS: We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed. METHOD: This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model. RESULTS: A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (P = 0.006). Controls showed a positive correlation between total grey matter volume and income (R = 0.14, P = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (R = -0.076, P = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure. CONCLUSIONS: Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.


Assuntos
Esquizofrenia , Encéfalo/diagnóstico por imagem , Cidades , Substância Cinzenta , Humanos , América Latina/epidemiologia , Imageamento por Ressonância Magnética , Pobreza , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/epidemiologia , Violência
6.
Brain Behav Immun ; 93: 214-225, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33508469

RESUMO

BACKGROUND: Major depressive disorder (MDD) is the leading cause of years lived with disability worldwide, and up to 40% of individuals with MDD do not respond to current treatments. Studies suggest that peripheral inflammation plays an important role in the striatal mesolimbic dopamine pathway and corticostriatal reward circuitry in MDD. Although MDD patients show blunted striatal responses to reward, the link between degree of inflammation and attenuation of reward processing is unclear. We investigated whether MDD patients with elevated peripheral inflammation exhibit attenuated reward responses to enhance our understanding of MDD pathophysiology and develop more effective treatments for current non-responders. METHODS: MDD subjects varying on serum C-reactive protein (CRP) concentrations (MDD-High CRP, >3 mg/L, n = 44; MDD-Low CRP, <3 mg/L, n = 44) and healthy comparisons (HC, n = 44) completed a monetary incentive delay (MID) task and provided blood samples to measure inflammation-related markers. MDD-High and MDD-Low were propensity score-matched on age, sex, body mass index (BMI), smoking status, exercise and MID task head motion. Percent change in blood oxygen level-dependent (BOLD) signal during anticipation of wins and losses was extracted from bilateral nucleus accumbens, dorsal caudate and dorsolateral putamen regions of interest (ROIs). A linear mixed-effects model was used to test group (MDD-High, MDD-Low and HC), condition (large-win, small-win and no win), and their interaction for these ROIs as well as whole-brain voxelwise data. Analyses also tested group differences in inflammatory mediators. Correlations were used to explore the relationship between inflammatory mediators and brain regions showing differences between MDD-High and MDD-Low. RESULTS: MDD-High exhibited: (a) lower BOLD signal change in dorsal caudate, thalamus, left insula and left precuneus during anticipation of small wins than MDD-Low; and (b) higher serum soluble intercellular adhesion molecule 1 (sICAM-1) and interleukin 6 (IL-6) concentrations than MDD-Low and HC. MDD as a whole, regardless of CRP-based inflammation, exhibited: (a) lower precuneus BOLD signal change to large wins than HC; and (b) higher Interleukin 1 receptor antagonist (IL-1ra), macrophage-derived chemokine (MDC) and macrophage inflammatory protein-1 alpha (MIP-1α) concentrations than HC. Higher serum sICAM-1 concentrations were associated with lower caudate BOLD signal change to small wins only within the MDD-High group. CONCLUSION: Within MDD patients, high inflammation (CRP, sICAM-1) was linked to reduced striatal activation recruited to discriminate intermediate reward magnitudes. These findings support an association between levels of peripheral inflammation and the degree of reward-related activation in individuals with MDD. REGISTRATION OF CLINICAL TRIALS: The ClinicalTrials.gov identifier for the clinical protocol associated with data published in this current paper is NCT02450240, "Latent Structure of Multi-level Assessments and Predictors of Outcomes in Psychiatric Disorders."


Assuntos
Transtorno Depressivo Maior , Corpo Estriado , Humanos , Inflamação , Imageamento por Ressonância Magnética , Motivação , Recompensa
7.
J Neuropsychiatry Clin Neurosci ; 31(1): 25-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30305005

RESUMO

Failure to recover from proactive semantic interference (frPSI) has been shown to be more sensitive than traditional cognitive measures in different populations with preclinical Alzheimer's disease. The authors sought to characterize the structural and amyloid in vivo correlates of frPSI in cognitively normal offspring of patients with late-onset Alzheimer's disease (O-LOAD), compared with individuals without a family history of neurodegenerative disorders (CS). The authors evaluated the LASSI-L, a test tapping frPSI and other types of semantic interference and delayed recall on the RAVLT, along with 3-T MRI volumetry and positron emission tomography Pittsburgh compound B, in 27 O-LOAD and 18 CS with equivalent age, sex, years of education, ethnicity, premorbid intelligence, and mood symptoms. Recovery from proactive semantic interference (frPSI) and RAVLT delayed recall were lower in O-LOAD cases. Structural correlates of both cognitive dimensions were different in CS and O-LOAD, involving brain regions concerned with autonomic, motor, and motivational control in the former, and regions traditionally implicated in Alzheimer's disease in the latter. Better recovery from retroactive semantic interference was associated with less amyloid load in the left temporal lobe in O-LOAD but not CS. In middle-aged cognitively normal individuals with one parent affected with LOAD, frPSI was impaired compared with persons without a family history of LOAD. The neuroimaging correlates of such cognitive measure in those with one parent with LOAD involve Alzheimer's-relevant brain regions even at a relatively young age.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Encéfalo , Disfunção Cognitiva , Predisposição Genética para Doença , Rememoração Mental/fisiologia , Adulto , Idade de Início , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Compostos de Anilina , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Tiazóis , Adulto Jovem
9.
Vertex ; XXVII(129): 393-396, 2016 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-28282077

RESUMO

We review the concept of endophenotype, and its relationship with related terms in use in the scientific literature, including "biomarker" and "intermediate phenotype". We then explain the importance of the concept in current psychiatry research. Specifically, we focus in the potential importance of endophenotypes in both disentangling the genetic causes, and improving the dimensional and pathophysiologic definition, of psychiatric nosological categories. After delineating which types of variables could constitute valid endophenotypes, we describe efforts in defining neurobiological signatures of social cognitive deficits in schizophrenia as an example with potential heuristic value.


Assuntos
Endofenótipos , Transtornos Mentais/genética , Humanos
10.
J Neuropsychiatry Clin Neurosci ; 27(4): 254-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26067439

RESUMO

Schizophrenia is characterized by profound deficits in social competence and functioning, independent from active psychotic symptoms at different stages of the disease. Social deficits in schizophrenia are clinically well characterized, but their neurobiological underpinnings are undetermined. This article reviews recent evidence supporting heritable deficits in a circuit necessary for appropriate naming of emotions and mental states in others, centered at the temporoparietal junction of the nondominant hemisphere. The clinical implications of this model are discussed, including the potential use of rehabilitation techniques oriented to recognition and naming of emotions and mental states as a necessary step for social rehabilitation.


Assuntos
Córtex Cerebral/fisiopatologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Comportamento Social , Percepção Social , Emoções , Expressão Facial , Humanos , Rede Nervosa/fisiopatologia , Testes Neuropsicológicos
11.
Alzheimers Dement ; 11(7): 850-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26194318

RESUMO

The Alzheimer's Disease Neuroimaging Initiative (ADNI), launched in 2004, has worked to accelerate drug development by validating imaging and blood/cerebrospinal fluid biomarkers for Alzheimer's disease clinical treatment trials. ADNI is a naturalistic (nontreatment) multisite longitudinal study. A true public-private partnership, the initiative has set a new standard for data sharing without embargo and for the use of biomarkers in dementia research. The ADNI effort in North America is not the only such effort in the world. The Alzheimer's Association recognized these global efforts and formed Worldwide ADNI (WW-ADNI). By creating a platform for international collaboration and cooperation, WW-ADNI's goals are to harmonize projects and results across geographical regions and to facilitate data management and availability to investigators around the world. WW-ADNI projects include those based in North America, Europe, Japan, Australia, Korea, and Argentina.


Assuntos
Doença de Alzheimer/diagnóstico , Saúde Global , Neuroimagem , Doença de Alzheimer/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Humanos
12.
bioRxiv ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38746338

RESUMO

Major Depressive Disorder (MDD) poses a significant public health challenge due to its high prevalence and the substantial burden it places on individuals and healthcare systems. Real-time functional magnetic resonance imaging neurofeedback (rtfMRI-NF) shows promise as a treatment for this disorder, although its mechanisms of action remain unclear. This study investigated whole-brain response patterns during rtfMRI-NF training to explain interindividual variability in clinical efficacy in MDD. We analyzed data from 95 participants (67 active, 28 control) with MDD from previous rtfMRI-NF studies designed to increase left amygdala activation through positive autobiographical memory recall. Significant symptom reduction was observed in the active group (t=-4.404, d=-0.704, p<0.001) but not in the control group (t=-1.609, d=-0.430, p=0.111). However, left amygdala activation did not account for the variability in clinical efficacy. To elucidate the brain training process underlying the clinical effect, we examined whole-brain activation patterns during two critical phases of the neurofeedback procedure: activation during the self-regulation period, and transient responses to feedback signal presentations. Using a systematic process involving feature selection, manifold extraction, and clustering with cross-validation, we identified two subtypes of regulation activation and three subtypes of brain responses to feedback signals. These subtypes were significantly associated with the clinical effect (regulation subtype: F=8.735, p=0.005; feedback response subtype: F=5.326, p=0.008; subtypes' interaction: F=3.471, p=0.039). Subtypes associated with significant symptom reduction were characterized by selective increases in control regions, including lateral prefrontal areas, and decreases in regions associated with self-referential thinking, such as default mode areas. These findings suggest that large-scale brain activity during training is more critical for clinical efficacy than the level of activation in the neurofeedback target region itself. Tailoring neurofeedback training to incorporate these patterns could significantly enhance its therapeutic efficacy.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38703822

RESUMO

BACKGROUND: Rumination is associated with greater cognitive dysfunction and treatment resistance in major depressive disorder (MDD), but its underlying neural mechanisms are not well understood. Because rumination is characterized by difficulty in controlling negative thoughts, the current study investigated whether rumination was associated with aberrant cognitive control in the absence of negative emotional information. METHODS: Individuals with MDD (n = 176) and healthy control individuals (n = 52) completed the stop signal task with varied stop signal difficulty during functional magnetic resonance imaging. In the task, a longer stop signal asynchrony made stopping difficult (hard stop), whereas a shorter stop signal asynchrony allowed more time for stopping (easy stop). RESULTS: In participants with MDD, higher rumination intensity was associated with greater neural activity in response to difficult inhibitory control in the frontoparietal regions. Greater activation for difficult inhibitory control associated with rumination was also positively related to state fear. The imaging results provide compelling evidence for the neural basis of inhibitory control difficulties in individuals with MDD with high rumination. CONCLUSIONS: The association between higher rumination intensity and greater neural activity in regions involved in difficult inhibitory control tasks may provide treatment targets for interventions aimed at improving inhibitory control and reducing rumination in this population.


Assuntos
Transtorno Depressivo Maior , Inibição Psicológica , Imageamento por Ressonância Magnética , Ruminação Cognitiva , Humanos , Masculino , Feminino , Adulto , Ruminação Cognitiva/fisiologia , Transtorno Depressivo Maior/fisiopatologia , Pessoa de Meia-Idade , Função Executiva/fisiologia , Adulto Jovem , Cognição/fisiologia , Mapeamento Encefálico
14.
Transl Psychiatry ; 14(1): 354, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39227376

RESUMO

Real-time fMRI neurofeedback (rtfMRI-NF) has emerged as a promising intervention for psychiatric disorders, yet its clinical efficacy remains underexplored due to an incomplete mechanistic understanding. This study aimed to delineate the whole-brain mechanisms underpinning the effects of rtfMRI-NF on repetitive negative thinking in depression. In a double-blind randomized controlled trial, forty-three depressed individuals underwent NF training targeting the functional connectivity (FC) between the posterior cingulate cortex and the right temporoparietal junction, linked to rumination severity. Participants were randomly assigned to active or sham groups, with the sham group receiving synthesized feedback mimicking real NF signal patterns. The active group demonstrated a significant reduction in brooding rumination scores (d = -1.52, p < 0.001), whereas the sham group did not (d = -0.23, p = 0.503). While the target FC did not show discernible training effects or group differences, connectome-based predictive modeling (CPM) analysis revealed that the interaction between brain activity during regulation and brain response to the feedback signal was the critical factor in explaining treatment outcomes. The model incorporating this interaction successfully predicted rumination changes across both groups. The FCs significantly contributing to the prediction were distributed across brain regions, notably the frontal control, salience network, and subcortical reward processing areas. These results underscore the importance of considering the interplay between brain regulation activities and brain response to the feedback signal in understanding the therapeutic mechanisms of rtfMRI-NF. The study affirms rtfMRI-NF's potential as a therapeutic intervention for repetitive negative thinking and highlights the need for a nuanced understanding of the whole-brain mechanisms contributing to its efficacy.


Assuntos
Conectoma , Imageamento por Ressonância Magnética , Neurorretroalimentação , Humanos , Neurorretroalimentação/métodos , Feminino , Masculino , Adulto , Método Duplo-Cego , Ruminação Cognitiva/fisiologia , Giro do Cíngulo/fisiopatologia , Giro do Cíngulo/diagnóstico por imagem , Adulto Jovem , Pessoa de Meia-Idade , Pessimismo , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Transtorno Depressivo Maior/terapia , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Resultado do Tratamento
15.
medRxiv ; 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39484283

RESUMO

Background: Repetitive negative thinking (RNT) in major depressive disorder (MDD) involves persistent focus on negative self-related experiences. Resting-state fMRI shows that the functional connectivity (FC) between the insula and the superior temporal sulcus is critical to RNT intensity. This study examines how insular FC patterns differ between resting-state and RNT-induction in MDD and healthy participants (HC). Methods: Forty-one individuals with MDD and twenty-eight HCs (total n=69) underwent resting-state and RNT-induction fMRI scans. Seed-to-whole brain analysis using insular subregions as seeds was performed. Results: No diagnosis-by-run interaction effects were observed across insular subregions. MDD participants showed greater FC between bilateral anterior, middle, and posterior insular regions and the cerebellum (z = 4.31 to 6.15). During RNT-induction, both MDD and HC participants demonstrated increased FC between bilateral anterior and middle insula and key brain regions, including prefrontal cortices, parietal lobes, posterior cingulate cortex, and medial temporal gyrus, encompassing the STS (z = 4.47 to 8.31). Higher trait-RNT was associated with increased FC between the right dorsal anterior and middle insula and regions in the DMN and salience network in MDD participants (z = 4.31 to 6.15). Greater state-RNT scores were linked to increased FC in similar insular regions, the bilateral angular gyrus and right middle temporal gyrus (z = 4.47 to 8.31). Conclusions: Hyperconnectivity in insula subregions during active rumination, especially involving the DMN and salience network, supports theories of heightened self-focused and negative emotional processing in depression. These findings emphasize the neural basis of RNT when actively elicited in MDD.

16.
J Affect Disord ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39326584

RESUMO

BACKGROUND: Repetitive negative thinking (RNT), particularly its brooding aspect, is a prominent feature in Major Depressive Disorder (MDD) with and without comorbid anxiety. Error processing, an adaptive cognitive operation, seems to be impaired in individuals with exaggerated RNT. This study measured a post-error neural response, error-related negativity (ERN), during an inhibitory task to examine the mechanism underlying the relationship between RNT and faulty error processing. METHODS: We examined current MDD patients with (n = 61) and without comorbid anxiety disorders (COM; n = 38), propensity-matched into High- or Low-RNT groups according to Ruminative Response Scale Brooding subscale scores. Using 32-channel electroencephalography (EEG) during a stop-signal task, we measured baseline-corrected ERN amplitude at FCz 0-100 ms after an incorrect response. A between-subjects ANOVA was conducted with group (High RNT, Low RNT) and comorbidity (MDD, COM) as factors. RESULTS: A significant group-by-comorbidity interaction (η2 = 0.07) was found, with MDD participants exhibiting high RNT revealing smaller (more positive) ERN amplitudes compared to their COM counterparts with high RNT (d = 0.77) and MDD participants with low RNT (d = 0.92). CONCLUSIONS: Non-anxious individuals with MDD and high RNT showed blunted post-error neural responses, potentially indicating a diminished adaptive neural mechanism for recognizing and correcting errors. However, the presence of comorbid anxiety disorders in individuals with high RNT appears to counteract this reduction, potentially through an enhanced neural response to errors, thereby maintaining a higher level of error-processing activity. Further understanding of these relationships is essential for developing targeted interventions for MDD, with particular focus on the detrimental impact of brooding RNT.

17.
J Affect Disord ; 366: 98-105, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39187192

RESUMO

BACKGROUND: Dysregulation of fear processing through altered sensitivity to threat is thought to contribute to the development of anxiety disorders and major depressive disorder (MDD). However, fewer studies have examined fear processing in MDD than in anxiety disorders. The current study used propensity matching to examine the hypothesis that comorbid MDD and anxiety (AnxMDD) shows greater neural correlates of fear processing than MDD, suggesting that the co-occurrence of AnxMDD is exemplified by exaggerated defense related processes. METHODS: 195 individuals with MDD (N = 65) or AnxMDD (N = 130) were recruited from the community and completed multi-level assessments, including a Pavlovian fear learning task during functional imaging. Visual images paired with threat (conditioned stimuli: CS+) were compared to stimuli not paired with threat (CS-). RESULTS: MDD and AnxMDD showed significantly different patterns of activation for CS+ vs CS- in the dorsal anterior insula/inferior frontal gyrus (partial eta squared; ηp2 = 0.02), dorsolateral prefrontal cortex (ηp2 = 0.01) and dorsal anterior/mid cingulate cortex (ηp2 = 0.01). These differences were driven by greater activation to the CS+ in AnxMDD versus MDD. LIMITATIONS: Limitations include the cross-sectional design, a scream US rather than shock and half the number of MDD as AnxMDD participants. CONCLUSIONS: AnxMDD showed a pattern of increased activation in regions identified with fear processing. Effects were consistently driven by threat, further suggesting fear signaling as the emergent target process. Differences emerged in regions associated with salience processing, attentional orienting/conflict, self-relevant processing and executive functioning in comorbid anxiety and depression, thereby highlighting potential treatment targets for this prevalent and treatment resistant group.


Assuntos
Transtornos de Ansiedade , Condicionamento Clássico , Transtorno Depressivo Maior , Medo , Giro do Cíngulo , Imageamento por Ressonância Magnética , Humanos , Masculino , Medo/fisiologia , Feminino , Giro do Cíngulo/fisiopatologia , Giro do Cíngulo/diagnóstico por imagem , Adulto , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Condicionamento Clássico/fisiologia , Transtornos de Ansiedade/fisiopatologia , Transtornos de Ansiedade/epidemiologia , Córtex Insular/fisiopatologia , Córtex Insular/diagnóstico por imagem , Pessoa de Meia-Idade , Comorbidade , Lobo Frontal/fisiopatologia , Lobo Frontal/diagnóstico por imagem , Adulto Jovem , Córtex Cerebral/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Ansiedade/fisiopatologia , Ansiedade/psicologia
18.
Psychiatry Res Neuroimaging ; 340: 111803, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38460393

RESUMO

Adverse childhood experiences (ACEs) negatively affect the function and structure of emotion brain circuits, increasing the risk of various psychiatric disorders. It is unclear if ACEs show disorder specificity with respect to their effects on brain structure. We aimed to investigate whether the structural brain effects of ACEs differ between patients with major depression (MDD) and borderline personality disorder (BPD). These disorders share many symptoms but likely have different etiologies. To achieve our goal, we obtained structural 3T-MRI images from 20 healthy controls (HC), 19 MDD patients, and 18 BPD patients, and measured cortical thickness and subcortical gray matter volumes. We utilized the Adverse Childhood Experiences (ACE) questionnaire to quantify self-reported exposure to childhood trauma. Our findings suggest that individuals with MDD exhibit a smaller cortical thickness when compared to those with BPD. However, ACEs showed a significantly affected relationship with cortical thickness in BPD but not in MDD. ACEs were found to be associated with thinning in cortical regions involved in emotional behavior in BPD, whereas HC showed an opposite association. Our results suggest a potential mechanism of ACE effects on psychopathology involving changes in brain structure. These findings highlight the importance of early detection and intervention strategies.


Assuntos
Experiências Adversas da Infância , Transtorno da Personalidade Borderline , Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/patologia , Depressão , Encéfalo , Personalidade
19.
Vertex ; 24(108): 155-7, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-24251303

RESUMO

The last several years have witnessed the accumulation of evidence suggesting that the Kraepelinian binary system of classification of the psychoses does not capture their true nature, as Kraepelin himself had cautioned in his late years. The long-awaited new edition of the APA's Diagnostic and Statistical Manual will in all probability incorporate symptom dimensions and suppress schizophrenia subtypes. However, the initial Kraepelinian conceptualization of the psychoses is maintained, along with the diagnostic category that epitomizes its obsolescence: schizoaffective disorder. We hereby make a brief critical appraisal of this fact, pointing out how the current classification system might be an obstacle to much-needed advances in this knowledge field.


Assuntos
Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtornos Psicóticos/diagnóstico , Humanos
20.
Artigo em Inglês | MEDLINE | ID: mdl-36969502

RESUMO

Major Depressive Disorder (MDD) and Obsessive-Compulsive Disorder (OCD) are common and potentially incapacitating conditions. Even when recognized and adequately treated, in over a third of patients with these conditions the response to first-line pharmacological and psychotherapeutic measures is not satisfactory. After more assertive measures including pharmacological augmentation (and in the case of depression, transcranial magnetic stimulation, electroconvulsive therapy, or treatment with ketamine or esketamine), a significant number of individuals remain severely symptomatic. In these persons, different ablation and deep-brain stimulation (DBS) psychosurgical techniques have been employed. However, apart from the cost and potential morbidity associated with surgery, on average only about half of patients show adequate response, which limits the widespread application of these potentially life-saving interventions. Possible reasons are considered for the wide variation in outcomes across different series of patients with MDD or OCD exposed to ablative or DBS psychosurgery, including interindividual anatomical and etiological variability. Low-intensity focused ultrasound (LIFU) is an emerging technique that holds promise in its ability to achieve anatomically circumscribed, noninvasive, and reversible neuromodulation of deep brain structures. A possible role for LIFU in the personalized presurgical definition of neuromodulation targets in the individual patient is discussed, including a proposed roadmap for clinical trials addressed at testing whether this technique can help to improve psychosurgical outcomes.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA