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1.
Neurosci Biobehav Rev ; 162: 105693, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38697379

RESUMO

Music and ketamine are both known to affect therapeutic outcomes, but few studies have investigated their co-administration. This scoping review describes the existing literature on the joint use of music and ketamine-or esketamine (the S(+) enantiomer of ketamine)-in humans. The review considers that extant studies have explored the intersection of ketamine/esketamine and music in healthy volunteers and in patients of various age groups, at different dosages, through different treatment processes, and have varied the sequence of playing music relative to ketamine/esketamine administration. Studies investigating the use of music during ketamine anesthesia are also included in the review because anesthesia and sedation were the early drivers of ketamine use. Studies pertaining to recreational ketamine use were omitted. The review was limited to articles published in the English language but not restricted by publication year. To the best of our knowledge, this scoping review is the first comprehensive exploration of the interplay between music and ketamine/esketamine and offers valuable insights to researchers interested in designing future studies.


Assuntos
Ketamina , Musicoterapia , Humanos , Anestésicos Dissociativos/administração & dosagem , Anestésicos Dissociativos/uso terapêutico , Ketamina/administração & dosagem , Ketamina/uso terapêutico , Depressão/tratamento farmacológico , Depressão/terapia , Manejo da Dor
2.
Sci Rep ; 14(1): 4538, 2024 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402253

RESUMO

The hippocampus and amygdala have been implicated in the pathophysiology and treatment of major depressive disorder (MDD). Preclinical models suggest that stress-related changes in these regions can be reversed by antidepressants, including ketamine. Clinical studies have identified reduced volumes in MDD that are thought to be potentiated by early life stress and worsened by repeated depressive episodes. This study used 3T and 7T structural magnetic resonance imaging data to examine longitudinal changes in hippocampal and amygdalar subfield volumes associated with ketamine treatment. Data were drawn from a previous double-blind, placebo-controlled, crossover trial of healthy volunteers (HVs) unmedicated individuals with treatment-resistant depression (TRD) (3T: 18 HV, 26 TRD, 7T: 17 HV, 30 TRD) who were scanned at baseline and twice following either a 40 min IV ketamine (0.5 mg/kg) or saline infusion (acute: 1-2 days, interim: 9-10 days post infusion). No baseline differences were noted between the two groups. At 10 days post-infusion, a slight increase was observed between ketamine and placebo scans in whole left amygdalar volume in individuals with TRD. No other differences were found between individuals with TRD and HVs at either field strength. These findings shed light on the timing of ketamine's effects on cortical structures.


Assuntos
Transtorno Depressivo Maior , Transtorno Depressivo Resistente a Tratamento , Ketamina , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/patologia , Voluntários Saudáveis , Hipocampo/patologia , Ketamina/farmacologia , Ketamina/uso terapêutico , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Sci Data ; 9(1): 518, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008415

RESUMO

The NIMH Healthy Research Volunteer Dataset is a collection of phenotypic data characterizing healthy research volunteers using clinical assessments such as assays of blood and urine, mental health assessments, diagnostic and dimensional measures of mental health, cognitive and neuropsychological functioning, structural and functional magnetic resonance imaging (MRI), along with diffusion tensor imaging (DTI), and a comprehensive magnetoencephalography battery (MEG). In addition, blood samples of healthy volunteers are banked for future analyses. All data collected in this protocol are broadly shared in the OpenNeuro repository, in the Brain Imaging Data Structure (BIDS) format. In addition, task paradigms and basic pre-processing scripts are shared on GitHub. There are currently few open access MEG datasets, and multimodal neuroimaging datasets are even more rare. Due to its depth of characterization of a healthy population in terms of brain health, this dataset may contribute to a wide array of secondary investigations of non-clinical and clinical research questions.


Assuntos
Imagem de Tensor de Difusão , Magnetoencefalografia , Encéfalo/diagnóstico por imagem , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , National Institute of Mental Health (U.S.) , Neuroimagem/métodos , Estados Unidos
4.
Neuroimage Rep ; 2(2)2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35692456

RESUMO

Currently, the gold standard for high-resolution mapping of cortical electrophysiological activity is invasive electrocorticography (ECoG), a procedure that carries with it the risk of serious morbidity and mortality. Due to these risks, the use of ECoG is largely limited to pre-surgical mapping in intractable epilepsy. Nevertheless, many seminal studies in neuroscience have utilized ECoG to explore domains such as visual perception, attention, auditory processing, and sensorimotor behavior. Studies such as these, occurring in patients with epilepsy rather than healthy controls, may lack generalizability, and are limited by the placement of the electrode arrays over the presumed seizure focus. This manuscript explores the use of optically pumped magnetometers (OPMs) to create a non-invasive alternative to ECoG, which we refer to as magnetocorticography. Because prior ECoG studies reveal that most cognitive processes are driven by multiple, simultaneous independent neuronal assemblies, we characterize the ability of a theoretical 56-channel dense OPM array to resolve simultaneous independent sources, and compare it to currently available SQUID devices, as well as OPM arrays with inter-sensor spacings more typical of other systems in development. Our evaluation of this theoretical system assesses many potential sources of error, including errors of sensor calibration and position. In addition, we investigate the influence of geometrical and anatomical factors on array performance. Our simulations reveal the potential of high-density, on-scalp OPM MEG devices to localize electrophysiological brain responses at unprecedented resolution for a non-invasive device.

5.
J Affect Disord ; 312: 188-197, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35728680

RESUMO

BACKGROUND: This study examined magnetoencephalographic (MEG) correlates of suicidal ideation (SI) and suicide attempt history in patients with treatment-resistant major depression (TRD) at baseline and following subanesthetic-dose ketamine infusion. METHODS: Twenty-nine drug-free TRD patients (12 suicide attempters/17 non-attempters) participated in a crossover randomized trial of ketamine. MEG data were collected during an attentional dot probe task with emotional face stimuli at baseline and several hours post-ketamine infusion. Synthetic aperture magnetometry was used to project source power in the theta, alpha, beta, and gamma frequencies for angry-neutral, happy-neutral, and neutral-neutral face pairings during a one-second peristimulus period. Mixed models were used to test for clinical, behavioral, and electrophysiological effects of group, emotion, session, and SI score. RESULTS: Ketamine significantly reduced SI and depression across the sample. Post-ketamine, attempters had improved accuracy and non-attempters had reduced accuracy on the task. SI was positively associated with gamma power in regions of the frontal and parietal cortices across groups. In an extended amygdala-hippocampal region, attempters differed significantly in their emotional reactivity to angry versus happy faces as indexed by theta power differences, irrespective of drug. Ketamine significantly reduced the association between alpha power and SI for angry compared with happy faces in a fronto-insular/anterior cingulate region important for regulating sensory attentiveness. LIMITATIONS: Limitations include a small sample size of attempters. CONCLUSIONS: The findings highlight key differences in band-limited power between attempters and non-attempters and reinforce previous findings that ketamine has distinct response properties in patients with a suicide history.


Assuntos
Transtorno Depressivo Maior , Ketamina , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Biomarcadores , Depressão/psicologia , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/psicologia , Humanos , Ketamina/farmacologia , Ketamina/uso terapêutico , Magnetoencefalografia , Ideação Suicida , Tentativa de Suicídio/psicologia
6.
Front Psychiatry ; 12: 673159, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220581

RESUMO

The glutamatergic modulator ketamine rapidly reduces depressive symptoms in individuals with treatment-resistant major depressive disorder (TRD) and bipolar disorder. While its underlying mechanism of antidepressant action is not fully understood, modulating glutamatergically-mediated connectivity appears to be a critical component moderating antidepressant response. This double-blind, crossover, placebo-controlled study analyzed data from 19 drug-free individuals with TRD and 15 healthy volunteers who received a single intravenous infusion of ketamine hydrochloride (0.5 mg/kg) as well as an intravenous infusion of saline placebo. Magnetoencephalographic recordings were collected prior to the first infusion and 6-9 h after both drug and placebo infusions. During scanning, participants completed an attentional dot probe task that included emotional faces. Antidepressant response was measured across time points using the Montgomery-Asberg Depression Rating Scale (MADRS). Dynamic causal modeling (DCM) was used to measure changes in parameter estimates of connectivity via a biophysical model that included realistic local neuronal architecture and receptor channel signaling, modeling connectivity between the early visual cortex, fusiform cortex, amygdala, and inferior frontal gyrus. Clinically, ketamine administration significantly reduced depressive symptoms in TRD participants. Within the model, ketamine administration led to faster gamma aminobutyric acid (GABA) and N-methyl-D-aspartate (NMDA) transmission in the early visual cortex, faster NMDA transmission in the fusiform cortex, and slower NMDA transmission in the amygdala. Ketamine administration also led to direct and indirect changes in local inhibition in the early visual cortex and inferior frontal gyrus and to indirect increases in cortical excitability within the amygdala. Finally, reductions in depressive symptoms in TRD participants post-ketamine were associated with faster α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) transmission and increases in gain control of spiny stellate cells in the early visual cortex. These findings provide additional support for the GABA and NMDA inhibition and disinhibition hypotheses of depression and support the role of AMPA throughput in ketamine's antidepressant effects. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT00088699?term=NCT00088699&draw=2&rank=1, identifier NCT00088699.

7.
Mol Psychiatry ; 26(7): 3292-3301, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32929215

RESUMO

Ketamine improves motivation-related symptoms in depression but simultaneously elicits similar symptoms in healthy individuals, suggesting that it might have different effects in health and disease. This study examined whether ketamine affects the brain's fronto-striatal system, which is known to drive motivational behavior. The study also assessed whether inflammatory mechanisms-which are known to influence neural and behavioral motivational processes-might underlie some of these changes. These questions were explored in the context of a double-blind, placebo-controlled, crossover trial of ketamine in 33 individuals with treatment-resistant major depressive disorder (TRD) and 25 healthy volunteers (HVs). Resting-state functional magnetic resonance imaging (rsfMRI) was acquired 2 days post-ketamine (final sample: TRD n = 27, HV n = 19) and post-placebo (final sample: TRD n = 25, HV n = 18) infusions and was used to probe fronto-striatal circuitry with striatal seed-based functional connectivity. Ketamine increased fronto-striatal functional connectivity in TRD participants toward levels observed in HVs while shifting the connectivity profile in HVs toward a state similar to TRD participants under placebo. Preliminary findings suggest that these effects were largely observed in the absence of inflammatory (C-reactive protein) changes and were associated with both acute and sustained improvements in symptoms in the TRD group. Ketamine thus normalized fronto-striatal connectivity in TRD participants but disrupted it in HVs independently of inflammatory processes. These findings highlight the potential importance of reward circuitry in ketamine's mechanism of action, which may be particularly relevant for understanding ketamine-induced shifts in motivational symptoms.


Assuntos
Transtorno Depressivo Maior , Transtorno Depressivo Resistente a Tratamento , Ketamina , Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Método Duplo-Cego , Humanos , Ketamina/farmacologia , Ketamina/uso terapêutico , Imageamento por Ressonância Magnética
8.
J Affect Disord ; 279: 239-249, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33074143

RESUMO

BACKGROUND: The glutamatergic modulator ketamine rapidly reduces depressive symptoms in individuals with treatment-resistant major depressive disorder (MDD). However, ketamine's effects on emotional processing biases remain largely unknown, and understanding these processes may help elucidate ketamine's mechanism of action. METHODS: Magnetoencephalography (MEG) was used to investigate ketamine's effects on early visual responses to affective stimuli in individuals with MDD (n=31) and healthy volunteers (HVs; n=24). Participants were enrolled in a double-blind, placebo-controlled, crossover clinical trial and were assessed at baseline and after subanesthetic-dose ketamine and placebo-saline infusions. During MEG recording, participants completed an emotional evaluation task in which they indicated the sex or emotional valence (happy-neutral or sad-angry) of facial stimuli. Source-localized event-related field (ERF) M100 and M170 amplitudes and latencies were extracted from regions of interest. Linear fixed effects models examined interactions between diagnosis, stimulus valence, and drug session for behavioral and MEG data. RESULTS: In baseline behavioral analyses, MDD participants exhibited higher accuracy for sad-angry than happy-neutral faces, and HVs responded faster to happy-neutral than sad-angry faces. In the MEG post-infusion analyses, calcarine M100 amplitudes were larger in MDD than HV participants post-placebo but became more similar post-ketamine. Finally, fusiform M170 amplitudes were associated with antidepressant response in MDD participants. LIMITATIONS: The modest sample size and the need to collapse across responses to happy and neutral faces to increase statistical power limit the generalizability of the findings. CONCLUSIONS: Ketamine rapidly altered emotional stimulus processing in MDD, laying the groundwork for future investigations of biomarkers of antidepressant treatment response. CLINICAL TRIAL: Clinicaltrials.gov, NCT#00088699.


Assuntos
Transtorno Depressivo Maior , Transtorno Depressivo Resistente a Tratamento , Ketamina , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Emoções , Expressão Facial , Humanos , Ketamina/farmacologia , Ketamina/uso terapêutico
9.
Front Psychiatry ; 11: 577628, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192714

RESUMO

Limited knowledge exists regarding the neurobiology of suicidal thoughts, given that there are currently no direct probes of the suicidal state. This pilot study used magnetoencephalography (MEG) to evaluate correlates of the implicit association between the self and death compared to the self and life as objective markers of suicide risk. Healthy volunteers (HVs; n=21) completed a modified version of the Suicide Implicit Association Task (S-IAT) during MEG scanning. Gamma power-which is considered a proxy measure of excitation-inhibition balance-was directly compared in the self-death/self-life contrast. As a proof-of-concept, the ability of dynamic causal modeling to categorize HVs versus four individuals with recent suicide crisis (SC) was evaluated. In HVs, enhanced gamma power in both amygdala and anterior insula were found for the self-death compared with self-life contrast. In addition, connectivity estimates between early visual cortex, anterior insula, and amygdala correctly categorized SC participants with 77% to 82% sensitivity and 80% to 85% specificity. These findings, which implicate network-level changes in salience network and amygdala connectivity in mediating suicidal associations, require further replication in larger samples. Direct probing of suicidal thoughts with the S-IAT may provide foundational markers of neural circuits associated with suicide risk.

10.
Neuroimage Clin ; 28: 102378, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32836087

RESUMO

Major depressive disorder (MDD) is highly heterogeneous in its clinical presentation. The present exploratory study used magnetoencephalography (MEG) to investigate electrophysiological intrinsic connectivity differences between healthy volunteers and unmedicated participants with treatment-resistant MDD. The study examined canonical frequency bands from delta through gamma. In addition to group comparisons, correlational studies were conducted to determine whether connectivity was related to five symptom factors: depressed mood, tension, negative cognition, suicidal thoughts, and amotivation. The MDD and healthy volunteer groups did not differ significantly at baseline when corrected across all frequencies and clusters, although evidence of generalized slowing in MDD was observed. Notably, however, electrophysiological connectivity was strongly related to suicidal thoughts, particularly as coupling of low frequency power fluctuations (delta and theta) with alpha and beta power. This analysis revealed hub areas underlying this symptom cluster, including left hippocampus, left anterior insula, and bilateral dorsolateral prefrontal cortex. No other symptom cluster demonstrated a relationship with neurophysiological connectivity, suggesting a specificity to these results as markers of suicidal ideation.


Assuntos
Transtorno Depressivo Maior , Córtex Cerebral , Humanos , Imageamento por Ressonância Magnética , Magnetoencefalografia , Ideação Suicida
11.
Front Psychiatry ; 11: 519, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655423

RESUMO

Major depressive disorder (MDD) is highly prevalent and frequently disabling. Only about 30% of patients respond to a first-line antidepressant treatment, and around 30% of patients are classified as "treatment-resistant" after failing to respond to multiple adequate trials. While most antidepressants target monoaminergic targets, ketamine is an N-methyl-D-aspartate (NMDA) antagonist that has shown rapid antidepressant effects when delivered intravenously or intranasally. While there is evidence that ketamine exerts its effects via enhanced α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) throughput, its mechanism for relieving depressive symptoms is largely unknown. This study acquired resting-state magnetoencephalography (MEG) recordings after both ketamine and placebo infusions and investigated functional connectivity using a multilayer amplitude-amplitude correlation technique spanning the canonical frequency bands. Twenty-four healthy volunteers (HVs) and 27 unmedicated participants with MDD took part in a double-blind, placebo-controlled, crossover trial of 0.5 mg/kg IV ketamine. Order of infusion was randomized, and participants crossed over to receive the second infusion after two weeks. The results indicated widespread ketamine-induced reductions in connectivity in the alpha and beta bands that did not correlate with magnitude of antidepressant response. In contrast, the magnitude of ketamine's antidepressant effects in MDD participants was associated with cross-frequency connectivity for delta-alpha and delta-gamma bands, with HVs and ketamine non-responders showing connectivity decreases post-ketamine and ketamine responders demonstrating small increases in connectivity. These results may indicate functional subtypes of MDD and also suggest that neural responses to ketamine are fundamentally different between responders and non-responders.

13.
Conscious Cogn ; 82: 102936, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32416543

RESUMO

Metacognition refers to awareness of one's own cognitive processes, including examining own biases and decision making. Metacognitive self (MCS), defined as accuracy in perception of own biases, is associated with pro-health behaviors and desire for feedback, including negative information. Two studies investigated MCS in relation to emotion and hedonic capacity. First, in a longitudinal study of college students, MCS measure was stable over time, and correlated with feelings of love and joy. In the second study, MCS, mood, and hedonic capacity ratings were collected prior to evaluating stimuli for pleasure from engagement during an fMRI. Higher MCS was associated with greater hedonic capacity and increased signal in cortical areas involved in self-reflection and decision making. Our findings implicate self-awareness of biases as a cognitive process supporting positive emotional state and hedonic capacity. Future studies should explore how MCS relates to changes in mood and vulnerability to mood disorders.


Assuntos
Conscientização/fisiologia , Córtex Cerebral/fisiologia , Tomada de Decisões/fisiologia , Metacognição/fisiologia , Prazer/fisiologia , Autoimagem , Adulto , Afeto/fisiologia , Córtex Cerebral/diagnóstico por imagem , Feminino , Felicidade , Humanos , Estudos Longitudinais , Amor , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
14.
Neuropsychopharmacology ; 45(8): 1398-1404, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32252062

RESUMO

A single, subanesthetic dose of (R,S)-ketamine (ketamine) exerts rapid and robust antidepressant effects. Several groups previously reported that (2S,6S;2R,6R)-hydroxynorketamine (HNK) had antidepressant effects in rodents, and that (2R,6R)-HNK increased cortical electroencephalographic gamma power. This exploratory study examined the relationship between ketamine metabolites, clinical response, psychotomimetic symptoms, and gamma power changes in 34 individuals (ages 18-65) with treatment-resistant depression (TRD) who received a single ketamine infusion (0.5 mg/kg) over 40 min. Plasma concentrations of ketamine, norketamine, and HNKs were measured at 40, 80, 120, and 230 min and at 1, 2, and 3 days post-infusion. Linear mixed models evaluated ketamine metabolites as mediators of antidepressant and psychotomimetic effects and their relationship to resting-state whole-brain magnetoencephalography (MEG) gamma power 6-9 h post-infusion. Three salient findings emerged. First, ketamine concentration positively predicted distal antidepressant response at Day 11 post-infusion, and an inverse relationship was observed between (2S,6S;2R,6R)-HNK concentration and antidepressant response at 3 and 7 days post-infusion. Norketamine concentration was not associated with antidepressant response. Second, ketamine, norketamine, and (2S,6S;2R,6R)-HNK concentrations at 40 min were positively associated with contemporaneous psychotomimetic symptoms; post-hoc analysis revealed that ketamine was the predominant contributor. Third, increased (2S,6S;2R,6R)-HNK maximum observed concentration (Cmax) was associated with increased MEG gamma power. While contrary to preclinical observations and our a priori hypotheses, these exploratory results replicate those of a recently published study documenting a relationship between higher (2S,6S;2R,6R)-HNK concentrations and weaker antidepressant response in humans and provide further rationale for studying gamma power changes as potential biomarkers of antidepressant response.


Assuntos
Transtorno Depressivo Maior , Ketamina , Antidepressivos/uso terapêutico , Estudos Cross-Over , Depressão , Transtorno Depressivo Maior/tratamento farmacológico , Humanos
15.
Artigo em Inglês | MEDLINE | ID: mdl-31928949

RESUMO

BACKGROUND: Defining the neurobiological underpinnings of suicidal ideation (SI) is crucial to improving our understanding of suicide. This study used magnetoencephalographic gamma power as a surrogate marker for population-level excitation-inhibition balance to explore the underlying neurobiology of SI and depression. In addition, effects of pharmacological intervention with ketamine, which has been shown to rapidly reduce SI and depression, were assessed. METHODS: Data were obtained from 29 drug-free patients with major depressive disorder who participated in an experiment comparing subanesthetic ketamine (0.5 mg/kg) with a placebo saline infusion. Magnetoencephalographic recordings were collected at baseline and after ketamine and placebo infusions. During scanning, patients rested with their eyes closed. SI and depression were assessed, and a linear mixed-effects model was used to identify brain regions where gamma power and both SI and depression were associated. Two regions of the salience network (anterior insula, anterior cingulate) were then probed using dynamic causal modeling to test for ketamine effects. RESULTS: Clinically, patients showed significantly reduced SI and depression after ketamine administration. In addition, distinct regions in the anterior insula were found to be associated with SI compared with depression. In modeling of insula-anterior cingulate connectivity, ketamine lowered the membrane capacitance for superficial pyramidal cells. Finally, connectivity between the insula and anterior cingulate was associated with improvements in depression symptoms. CONCLUSIONS: These findings suggest that the anterior insula plays a key role in SI, perhaps via its role in salience detection. In addition, transient changes in superficial pyramidal cell membrane capacitance and subsequent increases in cortical excitability might be a mechanism through which ketamine improves SI.


Assuntos
Transtorno Depressivo Maior , Antagonistas de Aminoácidos Excitatórios , Ketamina , Magnetoencefalografia , Ideação Suicida , Encéfalo/diagnóstico por imagem , Depressão/tratamento farmacológico , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/fisiopatologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Humanos , Ketamina/farmacologia , Escalas de Graduação Psiquiátrica
16.
Neuropsychopharmacology ; 45(6): 982-989, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31995812

RESUMO

Major depressive disorder (MDD) is associated with altered global brain connectivity (GBC), as assessed via resting-state functional magnetic resonance imaging (rsfMRI). Previous studies found that antidepressant treatment with ketamine normalized aberrant GBC changes in the prefrontal and cingulate cortices, warranting further investigations of GBC as a putative imaging marker. These results were obtained via global signal regression (GSR). This study is an independent replication of that analysis using a separate dataset. GBC was analyzed in 28 individuals with MDD and 22 healthy controls (HCs) at baseline, post-placebo, and post-ketamine. To investigate the effects of preprocessing, three distinct pipelines were used: (1) regression of white matter (WM)/cerebrospinal fluid (CSF) signals only (BASE); (2) WM/CSF + GSR (GSR); and (3) WM/CSF + physiological parameter regression (PHYSIO). Reduced GBC was observed in individuals with MDD only at baseline in the anterior and medial cingulate cortices, as well as in the prefrontal cortex only after regressing the global signal. Ketamine had no effect compared to baseline or placebo in either group in any pipeline. PHYSIO did not resemble GBC preprocessed with GSR. These results concur with several studies that used GSR to study GBC. Further investigations are warranted into disease-specific components of global fMRI signals that may drive these results and of GBCr as a potential imaging marker in MDD.


Assuntos
Transtorno Depressivo Maior , Ketamina , Antidepressivos/uso terapêutico , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Depressão , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Ketamina/uso terapêutico , Imageamento por Ressonância Magnética
17.
Brain Imaging Behav ; 14(2): 640, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31172359

RESUMO

The image of the Figure 2b in Figure 2 in the published article was incorrect and the authors would like to correct them. The original article has been corrected.

18.
BMC Psychiatry ; 19(1): 332, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675949

RESUMO

BACKGROUND: Despite decades of research, the rate of death from suicide is rising in the United States. Suicide is a complex and multifactorial phenomenon and, to date, no validated biomarkers that predict suicidal behavior have been identified. Only one FDA-approved drug to prevent suicide exists, and it is approved only for patients with schizophrenia. Although anti-suicide psychotherapeutic techniques exist, treatment takes time, and only preliminary data exist for rapid-acting therapies. DISCUSSION: While more research into suicidal ideation and acute suicidal behavior is clearly needed, this research is fraught with both practical and ethical concerns. As a result, many investigators and bioethicists have called for restrictions on the types of research that individuals with suicidal behavior can participate in, despite the fact that the available empirical evidence suggests that this research can be done safely. This manuscript presents background information on the phenomenology of suicide, discusses the current state of treatment and prevention strategies, and reviews the practical and ethical issues surrounding suicide research in the context of available empirical data. Currently, the causes of suicide are poorly understood, in part due to the fact that very few studies have investigated the acute suicidal crisis. Although some biomarkers for predicting risk have been developed, none have been sufficiently validated. The most successful current interventions involve means restriction. However, while numerous hurdles face researchers, these are not insurmountable. The available evidence suggests that research into suicide can be conducted both safely and ethically.


Assuntos
Transtornos Mentais/fisiopatologia , Transtornos Mentais/psicologia , Psicoterapia/ética , Prevenção do Suicídio , Suicídio/ética , Biomarcadores/análise , Feminino , Humanos , Masculino , Psicoterapia/métodos , Estados Unidos
19.
Hum Brain Mapp ; 40(13): 3940-3950, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31179620

RESUMO

Major depressive disorder (MDD) is highly prevalent and associated with considerable morbidity, yet its pathophysiology remains only partially understood. While numerous studies have investigated the neurobiological correlates of MDD, most have used only a single neuroimaging modality. In particular, diffusion tensor imaging (DTI) studies have failed to yield uniform results. In this context, examining key tracts and using information from multiple neuroimaging modalities may better characterize potential abnormalities in the MDD brain. This study analyzed data from 30 participants with MDD and 26 healthy participants who underwent DTI, magnetic resonance spectroscopy (MRS), resting-state functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG). Tracts connecting the subgenual anterior cingulate cortex (sgACC) and the left and right amygdala, as well as connections to the left and right hippocampus and thalamus, were examined as target areas. Reduced fractional anisotropy (FA) was observed in the studied tracts. Significant differences in the correlation between medial prefrontal glutamate concentrations and FA were also observed between MDD and healthy participants along tracts connecting the sgACC and right amygdala; healthy participants exhibited a strong correlation but MDD participants showed no such relationship. In the same tract, a correlation was observed between FA and subsequent antidepressant response to ketamine infusion in MDD participants. Exploratory models also suggested group differences in the relationship between DTI, fMRI, and MEG measures. This study is the first to combine MRS, DTI, fMRI, and MEG data to obtain multimodal indices of MDD and antidepressant response and may lay the foundation for similar future analyses.


Assuntos
Cérebro , Transtorno Depressivo Maior , Imagem Multimodal , Neuroimagem , Adulto , Cérebro/diagnóstico por imagem , Cérebro/metabolismo , Cérebro/patologia , Cérebro/fisiopatologia , Conectoma , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/patologia , Transtorno Depressivo Maior/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Brain Imaging Behav ; 13(6): 1624-1634, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31030316

RESUMO

Anhedonia-broadly defined as loss of interest and/or an inability to experience pleasure-is an important feature of several psychiatric disorders. Research into the clinical presentation and neurobiology of this symptom has identified components related to motivation, learning, anticipation, and experience of pleasure as important constructs that inform therapeutic interventions. The experimental study of anhedonia is largely based on incentive processing paradigms, most often with monetary rewards, though studies have also used pleasantness ratings of various stimuli. However, linking an individual's own system of reinforcers and ability to enjoy them with anhedonia and neural activity remains comparatively under-explored. A previous study of participants with major depressive disorder (MDD) and healthy controls found that activity word ratings correlated with measures of anhedonia, depression, and motivation. The present study collected functional magnetic resonance imaging (fMRI) images in healthy controls while they rated activity words and pictures showing activities in order to identify networks differentially responsive to subjective decisions about the appetitive value of activities. The study sought to measure individually-relevant hedonic capacity as demonstrated by correlations between task measures and anticipatory anhedonia ratings. Ratings of potential pleasure were associated with neural activity in areas previously identified as relevant to pleasure and reward processing, such as anterior and posterior cingulate, middle frontal areas, and dorsal and ventral striatum. Although the study included only healthy controls, the results demonstrate a link between anhedonia measures, behavior, and brain responses and also test a paradigm that could be used to study anhedonia in clinical populations.


Assuntos
Anedonia/fisiologia , Mapeamento Encefálico , Aprendizagem , Imageamento por Ressonância Magnética , Recompensa , Adulto , Feminino , Giro do Cíngulo/fisiologia , Humanos , Masculino , Motivação , Tempo de Reação/fisiologia , Inquéritos e Questionários , Estriado Ventral/fisiologia
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