Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros

País/Região como assunto
Intervalo de ano de publicação
1.
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.

2.
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
3.
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
4.
bioRxiv ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38562901

RESUMO

This study investigated the relationship between gut microbiota and neuropsychiatric disorders (NPDs), specifically anxiety disorder (ANXD) and/or major depressive disorder (MDD), as defined by DSM-IV or V criteria. The study also examined the influence of medication use, particularly antidepressants and/or anxiolytics, classified through the Anatomical Therapeutic Chemical (ATC) Classification System, on the gut microbiota. Both 16S rRNA gene amplicon sequencing and shallow shotgun sequencing were performed on DNA extracted from 666 fecal samples from the Tulsa-1000 and NeuroMAP CoBRE cohorts. The results highlight the significant influence of medication use; antidepressant use is associated with significant differences in gut microbiota beta diversity and has a larger effect size than NPD diagnosis. Next, specific microbes were associated with ANXD and MDD, highlighting their potential for non-pharmacological intervention. Finally, the study demonstrated the capability of Random Forest classifiers to predict diagnoses of NPD and medication use from microbial profiles, suggesting a promising direction for the use of gut microbiota as biomarkers for NPD. The findings suggest that future research on the gut microbiota's role in NPD and its interactions with pharmacological treatments are needed.

5.
Comput Psychiatr ; 6(1): 117-141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38774781

RESUMO

Computational modelling is a promising approach to parse dysfunctional cognitive processes in substance use disorders (SUDs), but it is unclear how much these processes change during the recovery period. We assessed 1-year follow-up data on a sample of treatment-seeking individuals with one or more SUDs (alcohol, cannabis, sedatives, stimulants, hallucinogens, and/or opioids; N = 83) that were previously assessed at baseline within a prior computational modelling study. Relative to healthy controls (HCs; N = 48), these participants were found at baseline to show altered learning rates and less precise action selection while completing an explore-exploit decision-making task. Here we replicated these analyses when these individuals returned and re-performed the task 1 year later to assess the stability of baseline differences. We also examined whether baseline modelling measures could predict symptoms at follow-up. Bayesian and frequentist analyses indicated that: (a) group differences in learning rates were stable over time (posterior probability = 1); and (b) intra-class correlations (ICCs) between model parameters at baseline and follow-up were significant and ranged from small to moderate (.25 ≤ ICCs ≤ .54). Exploratory analyses also suggested that learning rates and/or information-seeking values at baseline were associated with substance use severity at 1-year follow-up in stimulant and opioid users (.36 ≤ rs ≤ .43). These findings suggest that learning dysfunctions are moderately stable during recovery and could correspond to trait-like vulnerability factors. In addition, computational measures at baseline had some predictive value for changes in substance use severity over time and could be clinically informative.

6.
Arq. neuropsiquiatr ; 76(4): 231-240, Apr. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888379

RESUMO

ABSTRACT The Argentina-Alzheimer's disease neuroimaging initiative (Arg-ADNI) study is a longitudinal prospective cohort of 50 participants at a single institution in Buenos Aires, Argentina. Longitudinal assessments on a neuropsychological test battery were performed on 15 controls, 24 mild cognitive impairment (MCI) patients and 12 Alzheimer's disease (AD) dementia patients. In our study population, there was a high prevalence of positive AD biomarkers in the AD group, 92.3% (12/13); and a low prevalence in the normal controls, 20%; almost half (48%) of the patients diagnosed with MCI had positive amyloid detection. After a one year, the significant differences found at baseline on neuropsychological testing were similar at the follow-up assessment even though the AD group had significantly altered its functional performance (FAQ and CDR). The exception was semantic fluency, which showed greater impairment between the AD group and MCI and normal controls respectively. For these tests, the addition of AD biomarkers as a variable did not significantly alter the variations previously found for the established clinical group's model. Finally, the one-year conversion rate to dementia was 20% in the MCI cohort.


RESUMO El estudio de Argentina-Alzheimer's Disease Neuroimaging Initiative (Arg-ADNI) es una cohorte prospectiva de 50 pacientes seguidos en una misma institución. Fueron evaluados cognitivamente 15 controles normales (CN), 24 sujetos con deterioro cognitivo leve (DCL) y 12 con demencia tipo Alzheimer (DTA) leve. En los DTA, 92,3% tuvieron biomarcadores positivos para Alzheimer y 20% en los CN. Casi la mitad de los DCL presentaron biomarcadores positivos. Después de un año de seguimiento, la diferencias significativas halladas en la visita de inicio en las pruebas cognitivas fueron similares al año aunque los DTA tuvieron empeoramiento funcional medido en el FAQ y CDR. La excepción fue la fluencia semántica, la cual mostró mayor declinación entre DTA y los demás grupos. La incorporación de los biomarcadores como variable no alteró significativamente los hallazgos de grupo. La tasa de conversión a demencia anual fue del 20%.


Assuntos
Humanos , Masculino , Feminino , Idoso , Biomarcadores/líquido cefalorraquidiano , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Argentina , Índice de Gravidade de Doença , Imageamento por Ressonância Magnética , Estudos de Casos e Controles , Seguimentos , Estudos Longitudinais , Tomografia por Emissão de Pósitrons
7.
Vertex rev. argent. psiquiatr ; 24(108): 155-7, 2013 Mar-Apr.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1176888

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
8.
Rev. argent. cardiol ; 66(6): 607-17, nov.-dic. 1998.
Artigo em Espanhol | LILACS | ID: lil-239462

RESUMO

El presente estudio revisa las interacciones entre enfermedad cardiovascular y depresión. En pacientes con enfermedad cardiovascular conocida, la depresión empeora el pronóstico, siendo esto especialmente evidente en sobrevivientes de infarto de miocardio. Los individuos que desarrollan depresión parecen asimismo tener un riesgo aumentado de desarrollo ulterior de enfermedad cardiovascular. Se ofrece una hipótesis que vincula ambos cuadros y se revisan estrategias de manejo de la depresión en pacientes cardiológicos


Assuntos
Humanos , Doenças Cardiovasculares/psicologia , Depressão/complicações , Depressão/etiologia , Depressão/tratamento farmacológico , Antidepressivos/uso terapêutico , Infarto do Miocárdio/mortalidade , Fatores de Risco
9.
Artigo em Inglês | LILACS | ID: lil-134658

RESUMO

In 57 patients with psicovegetative disorders and abnormal MMPI, abnormality in MMPI scales indicating hypochondriasis, hysteria, gender deviant, paranoia, psychastenia, schizophrenia, hypomania or introversion was accompanied by increased plasma catecholamine levels and/or responses to hypoglycemia or by an increased cardiovascular reactivity. A high depression scale was associated with lower plasma catecholamine levels. Blunted plasma growth hormone responses to hypoglycemia were found in abnormal hypomania scale, and augmented responses of plasma cortisol in abnormal hysteria or schizophrenia scales. Paranoia and hypomania traits correlated with absence of morning-evening differences in blood cortisol levels. Electrodermal responses compatible with increased sympathetic activity correlated with high hysteria, gender, paranoia, schizophrenia or hypomania MMPI scales. This study indicates that most psychopathological traits in MMPI are accompanied by humoral and/or electrophysiological signs of abnormality of the autonomic nervous system


Assuntos
Humanos , Masculino , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Doenças do Sistema Nervoso Autônomo/psicologia , MMPI , Adolescente , Adulto , Idoso , Dexametasona , Epinefrina/sangue , Resposta Galvânica da Pele/fisiologia , Hidrocortisona/sangue , Pessoa de Meia-Idade , Sistemas Neurossecretores/fisiopatologia , Norepinefrina/sangue , Hormônio do Crescimento/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA