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1.
Neuroimage Clin ; 25: 102187, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31982681

RESUMO

OBJECTIVE: Subclinical or subthreshold depressive symptoms (StD) are frequent in adolescence and are related to suicidality and onset of depression in adulthood, however, their neurobiology is poorly understood. We examined the relationship between StD and subcortical grey matter structures in unmedicated adolescents with no history of axis I diagnosis. METHODS: 277 youths from Chicago aged 14 years participated, undergoing a structural MRI scan and completing the Revised Children's Anxiety and Depression Scale (RCADS). Blood samples provided a composite of five pro-inflammatory cytokines. Regions of interest (ROI) for vertex-based surface analysis were the left and right amygdala, hippocampus, thalamus, caudate, nucleus accumbens, pallidum and putamen. Covariates were age, pubertal status, socioeconomic disadvantage and intracranial volume. Males and females were analysed separately. RESULTS: StD had positive associations (outward shape) with subcortical morphology in the right amygdala and left hippocampus in females, and the bilateral putamen and the left caudate, hippocampus and thalamus in males. However, we also found negative associations with StD (inward contractions) in the hippocampus in females and the caudate in males. Pro-inflammatory cytokines did not mediate the relationship between StD and outward morphology or volume. CONCLUSION: This is one of the first studies to examine subcortical morphology of basal ganglia and thalamic regions related to StD in adolescents, and the first study to report mostly positive associations between StD, volume and outward morphology in youths. These findings could reflect intact neurogenesis or resilience to depression, however longitudinal research is needed to further understand the neurobiology of StD in adolescents.

2.
Hum Brain Mapp ; 41(1): 162-171, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31571360

RESUMO

Low socioeconomic status (SES) is associated with a higher probability of multiple exposures (e.g., neighborhood violence, poor nutrition, housing instability, air pollution, and insensitive caregiving) known to affect structural development of subcortical brain regions that subserve threat and reward processing, however, few studies have examined the relationship between SES and such subcortical structures in adolescents. We examined SES variations in volume and surface morphometry of subcortical regions. The sample comprised 256 youth in eighth grade (mean age = 13.9 years), in whom high dimensional deformation mapping of structural 3T magnetic resonance imaging scans was performed. Vertex-wise linear regression analyses examined associations between income to poverty ratio and surfaces of the hippocampus, amygdala, thalamus, caudate, putamen, nucleus accumbens and pallidum, with the covariates age, pubertal status, and intracranial volume. Given sex differences in pubertal development and subcortical maturation at this age, the analyses were stratified by sex. Among males, who at this age average an earlier pubertal stage than females, the relationship between SES and local shape variation in subcortical regions was almost entirely positive. For females, the relationship between SES and local shape variation was negative. Racial identity was associated with SES in our sample, however supplementary analyses indicated that most of the associations between SES and subcortical structure were independent of it. Although these cross-sectional results are not definitive, they are consistent with a scenario where low SES delays structural maturation of subcortical regions involved with threat and reward processing. Future longitudinal studies are needed to test this hypothesis.

3.
Psychol Med ; : 1-11, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31597581

RESUMO

BACKGROUND: Little is known about the neural substrates of suicide risk in mood disorders. Improving the identification of biomarkers of suicide risk, as indicated by a history of suicide-related behavior (SB), could lead to more targeted treatments to reduce risk. METHODS: Participants were 18 young adults with a mood disorder with a history of SB (as indicated by endorsing a past suicide attempt), 60 with a mood disorder with a history of suicidal ideation (SI) but not SB, 52 with a mood disorder with no history of SI or SB (MD), and 82 healthy comparison participants (HC). Resting-state functional connectivity within and between intrinsic neural networks, including cognitive control network (CCN), salience and emotion network (SEN), and default mode network (DMN), was compared between groups. RESULTS: Several fronto-parietal regions (k > 57, p < 0.005) were identified in which individuals with SB demonstrated distinct patterns of connectivity within (in the CCN) and across networks (CCN-SEN and CCN-DMN). Connectivity with some of these same regions also distinguished the SB group when participants were re-scanned after 1-4 months. Extracted data defined SB group membership with good accuracy, sensitivity, and specificity (79-88%). CONCLUSIONS: These results suggest that individuals with a history of SB in the context of mood disorders may show reliably distinct patterns of intrinsic network connectivity, even when compared to those with mood disorders without SB. Resting-state fMRI is a promising tool for identifying subtypes of patients with mood disorders who may be at risk for suicidal behavior.

4.
Brain Imaging Behav ; 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30937828

RESUMO

Executive dysfunctions are common in individuals with Traumatic Brain Injury (TBI). However, change in functional neural coupling of default and executive networks in the post-acute phase (≥ 1 month after injury) patients over time has yet to be understood. During a 5-week observation period, we examined changes in the goal-oriented executive function networks in 20 TBI participants, using a face/scene matching 1-back fMRI task (Chen et al. 2011). We conducted multivariate pattern analysis to assess working memory and visual selective attention, followed by a repeat-measures ANOVA to examine longitudinal changes, with a cluster FDR at p = .001. Results showed that task accuracy significantly improved after follow-up. Significantly increased activity patterns over time were observed in the right dorsolateral prefrontal cortex and right insula. Decreased activity patterns were seen in the left posterior cingulate cortex (PCC), bilateral precuneus, right inferior occipital gyrus and right temporo-occipital junction. Improvement in task accuracy correlated with decreased activity patterns in the PCC (r = -0.478, p = 0.031) and temporo-occipital junction (r = -0.592, p = 0.006), which were interpreted as neural plastic changes. However, we did not observe the default mode network (DMN)-executive network decoupling during task performance that is found in other studies. These results suggest that fMRI of attentional task performance could serve as a potential biomarker for neural plasticity of selective attention in TBI patients in the post-acute phase.

5.
J Clin Exp Neuropsychol ; 41(5): 512-529, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30913988

RESUMO

INTRODUCTION: Neuropsychological tests are designed to assay brain function via performance measurements. Many tests corresponding to visual and motor cortex function have been validated. Tests probing reward circuitry, including the ventral striatum (VS), could benefit assessment of numerous neurological and psychiatric disorders in which reward or VS function is disturbed. The present study sought to examine convergent and divergent validity of our modified, titrated version of the Monetary Incentive Delay Task, such that it may in the future stand as a validated neuropsychological test for reward function. METHOD: Participants were 132 individuals with a history of mood disturbance (HMD) and 43 healthy comparisons, ages 18-30 years. In addition to a standard neuropsychological battery and symptom measures, participants completed a modified version of the Monetary Incentive Delay Task (T-MIDT) during functional magnetic resonance imaging (fMRI), which involved a multistage titration procedure to incrementally increase or decrease the response window time per each participant's psychomotor speed and optimize individual performance. RESULTS: Across groups after titration, performance on the T-MIDT diverged from measures of processing speed, attention, and spatial working memory, but not inhibitory control. Performance in the HMD group was differentially correlated with executive function measures before and after titration. The reward circuit (e.g., subcortical, insular, medial prefrontal) was activated during reward anticipation. CONCLUSION: The present findings provide preliminary evidence that the T-MIDT measures a construct distinct from many executive functions and that individualized titration of the task parameters is critical in parsing reward from executive function. The T-MIDT correlated with residual mood symptoms in individuals with remitted depression or bipolar disorder, implying that behavioral or brain activation group differences are only to be observed in the active state of illness.

6.
Psychoneuroendocrinology ; 104: 219-227, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30889471

RESUMO

BACKGROUND: We have previously demonstrated that pre-scan salivary cortisol is associated with attentuated frontal-subcortical brain activation during emotion processesing and semantic list-learning paradigms in depressed subjects. Additionally, altered functional connectivity is observed after remission of acute depression symptoms (rMDD). It is unknown whether cortisol also predicts altered functional connectivity during remission. METHODS: Participants were 47 healthy controls (HC) and 73 rMDD, 18-30 years old who provided salivary cortisol samples before and after undergoing resting-state fMRI. We tested whether salivary cortisol by diagnosis interactions were associated with seed-based resting connectivity of the default mode (DMN) and salience and emotion (SN) networks using whole-brain, cluster-level corrected (p < .01) regression in SPM8. RESULTS: Pre-scan cortisol predicted decreased (HC) and increased (rMDD) cross-network connectivity to the dorsal anterior cingulate, dorso-medial and lateral- prefrontal cortex, brain stem and cerebellum (all seeds) and precuneus (DMN seeds). By and large, pre/post-scan cortisol change predicted the same pattern of findings. In network analyses, cortisol predominantly predicted enhanced cross-network connectivity to cognitive control network regions in rMDD. CONCLUSIONS: The association of cortisol with connections of default and salience networks to executive brain networks differs between individuals with and without a history of depression. Further investigation is needed to better understand the role of cortisol and related stress hormones as a potential primary and interactive driver of network coherence in depression.

7.
Neuropsychol Rev ; 29(2): 220-243, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877420

RESUMO

The importance of the amygdala as a salience detector and in emotional learning is now well accepted. The mechanisms that regulate and inhibit the amygdala, however, are less well understood. This review provides evidence from imaging and lesion studies to support the role of the ventromedial prefrontal cortex (vmPFC) as a moderator and inhibitor of the amygdala. The dual inhibition model centres on the broadly defined ventromedial prefrontal cortex (vmPFC) and the distinct role of two of its subcomponents, the rostral anterior cingulate cortex and orbitofrontal cortex. The dual inhibition model posits that these two regions, along with their associated inhibitory pathways, must interact for adequate inhibitory control of the amygdala and emotional regulation. Following a description of the model's experimental support, it is then proposed as a neuropsychological mechanism for post-traumatic stress disorder (PTSD). Flashbacks, as a defining feature of PTSD, are described in terms of a subcortical orienting network. Finally, there is a discussion of how a neuropsychological understanding of post-traumatic stress disorder (PTSD) might inform a clinician's approach to treatment and how the dual inhibition model might have a more general application to understanding emotional dysregulation.

8.
Appl Neuropsychol Adult ; : 1-9, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30811264

RESUMO

Memory difficulties are consistently reported in Major Depressive Disorder (MDD). Nonetheless, it has not been thoroughly investigated as to whether these deficits persist during remission from MDD. A group of 32 healthy young adults with no history of a mood disorder (Mage = 20.8, SD = 2.1) and 62 remitted depressed young adults (Mage = 21.1, SD = 1.9) completed a neuropsychological battery. The test battery included two measures of nonverbal memory, two measures of verbal memory, and a measure of performance validity. The testing session was repeated three to six weeks later to determine performance stability. No differences were found between healthy controls and remitted depressed patients in either memory domain (all ps > .05) and improvement in performance was exhibited over time for both groups (p = 0.004). Potential practice effects are examined. We found a stronger performance for women than men (p = 0.003), particularly for the Semantic List Learning Task (SLLT) (p = .047). Verbal and nonverbal memory and effort may not be impacted in those who are in a remitted state of MDD, early in the course of the illness. Women demonstrated auditory memory superiority over men, similar to prior research.

9.
J Neuropsychol ; 13(1): 136-146, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28419772

RESUMO

OBJECTIVE: Deficits in memory have been suggested as an influential mechanism of anhedonia, because while pleasant experiences may be enjoyed in-the-moment, the cognitive processes involved in reporting anticipated or remembered enjoyable experiences is thought to be impaired. This study will determine whether any aspects of memory, including visual memory, verbal memory or working memory, are significantly predictive of anhedonia in a sample of schizophrenia, psychotic bipolar disorder and healthy controls. METHODS: The study included 38 individuals with schizophrenia, 19 individuals with bipolar disorder with psychosis, and 43 age-matched healthy controls. All participants completed a self-report social and physical anhedonia questionnaire along with a cognitive screening battery, which assessed the domains of attention/vigilance, working memory, verbal learning, visual learning, and reasoning and problem-solving. RESULTS: Anhedonia scores were regressed onto domain scores to determine which areas of cognition uniquely predicted level of anhedonia in each group. For the schizophrenia group, physical anhedonia was significantly predicted by worse visual memory performance. The regression models did not find significant cognitive predictors of physical or social anhedonia in the bipolar disorder or control groups. CONCLUSIONS: This study found a significant relationship between visual memory and physical anhedonia in schizophrenia patients that was not present in a sample of psychotic bipolar patients or healthy controls, adding to an accumulating body of evidence that visual memory is related to anhedonia in schizophrenia. This relationship may be explained by underlying abnormalities in the orbitofrontal cortex in schizophrenia.

10.
Brain Connect ; 8(9): 527-536, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30411975

RESUMO

Attrition is a major problem in longitudinal neuroimaging studies, as it may lead to unreliable estimates of the stability of trait-like processes over time, of the identification of risk factors for clinical outcomes, and of the effects of treatment. Identification of characteristics associated with attrition has implications for participant recruitment and participant retention to achieve representative longitudinal samples. We investigated inhibitory control deficits, head motion, and resting-state functional connectivity within the cognitive control network (CCN) as predictors of attrition. Ninety-seven individuals with remitted major depressive disorder or healthy controls completed a functional magnetic resonance imaging scan, which included a go/no-go task and resting-state functional connectivity. Approximately 2 months later, participants were contacted and invited to return for a second scan. Seventeen individuals were lost to follow-up or declined to participate in the follow-up scan. Worse inhibitory control was correlated with greater movement within the scanner, and each predicted a greater likelihood of attrition, with movement mediating the effects of inhibitory control on attrition. Individuals who dropped out of the study exhibited greater movement than nondropouts across 9 of the 14 runs of the scan, with medium-to-large effect sizes. Finally, exploratory analyses suggested that attenuated resting-state connectivity with the CCN (particularly in bilateral dorsolateral prefrontal cortex) was associated with greater likelihood of attrition after accounting for head motion at several levels of analysis. Inhibitory control and movement within the scanner are associated with attrition, and should be considered for strategic oversampling and participant retention strategies to ensure generalizability of results in longitudinal studies.


Assuntos
Previsões/métodos , Perda de Seguimento , Imagem por Ressonância Magnética/métodos , Adolescente , Biomarcadores , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Cognição/fisiologia , Conectoma/métodos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/psicologia , Feminino , Movimentos da Cabeça/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Vias Neurais/fisiopatologia , Neuroimagem/métodos , Testes Neuropsicológicos , Descanso , Adulto Jovem
11.
Soc Cogn Affect Neurosci ; 13(10): 1081-1090, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30285231

RESUMO

Individuals in a major depressive episode often display impairment in cognitive control, and this impairment exists outside of the acute phase of illness. Impairment in cognitive control also has been associated with exposure to childhood adversity (CA). The current study examined whether exposure to CA can explain variance in a component of cognitive control-inhibitory control-independent of diagnostic status in young adults with and without a history of depression. Healthy control individuals (n = 40) and individuals with remitted major depressive disorder (n = 53) completed a task measuring inhibitory control, reported level of CA and completed a scanning session to assess gray matter volume and resting state connectivity in regions associated with cognitive control. The results demonstrate that higher levels of CA were associated with poorer inhibitory control, reduced right middle frontal gyrus gray matter, decreased connectivity of salience and emotion networks and increased connectivity in cognitive control networks, even after controlling for diagnostic status, residual depression symptoms and current stressors. Together, the results suggest that inhibitory control impairment and intrinsic connectivity changes may be characterized as developmental sequelae of early stress exposure.


Assuntos
Encéfalo/diagnóstico por imagem , Cognição/fisiologia , Transtorno Depressivo Maior/diagnóstico por imagem , Função Executiva/fisiologia , Substância Cinzenta/diagnóstico por imagem , Adolescente , Transtorno Depressivo Maior/psicologia , Emoções , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Adulto Jovem
12.
Neuroimage Clin ; 20: 1001-1009, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30321791

RESUMO

BACKGROUND: Major Depressive Disorder (MDD) is a prevalent, disruptive illness. A majority of those with MDD are at high risk for recurrence and increased risk for morbidity and mortality. This study examined whether multimodal baseline (and retest) Cognitive Control performance and neuroimaging markers (task activation and neural connectivity between key brain nodes) could differentiate between those with and without future recurrence of a major depressive (MD) episode within one year. We hypothesized that performance and neuroimaging measures of Cognitive Control would identify markers that differ between these two groups. METHODS: A prospective cohort study of young adults (ages 18-23) with history (h) of early-onset MDD (N = 60), now remitted, and healthy young adults (N = 49). Baseline Cognitive Control measures of performance, task fMRI and resting state connectivity (and reliability retest 4-12 weeks later) were used to compare those with future recurrence of MDD (N = 21) relative to those without future recurrence of MDD (N = 34 with resilience). The measures tested were (1) Parametric Go/No-Go (PGNG) performance, and task activation for (2) PGNG Correct Rejections, (3) PGNG Commission errors, and (4 & 5), resting state connectivity analyses of Cognitive Control Network to and from subgenual anterior cingulate. RESULTS: Relative to other groups at baseline, the group with MDD Recurrence had less bilateral middle frontal gyrus activation during commission errors. MDD Recurrence exhibited greater connectivity of right middle frontal gyrus to subgenual anterior cingulate (SGAC). SGAC connectivity was also elevated in this group to numerous regions in the Cognitive Control Network. Moderate to strong ICCs were present from test to retest, and highest for rs-fMRI markers. There were modest, significant correlations between task, connectivity and behavioral markers that distinguished between groups. CONCLUSION: Markers of Cognitive Control function could identify those with early course MD who are at risk for depression recurrence. Those at high risk for recurrence would benefit from maintenance or preventative treatments. Future studies could test and validate these markers as potential predictors, accounting for sample selection and bias in feature detection.


Assuntos
Cognição/fisiologia , Depressão/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Neuroimagem , Adolescente , Adulto , Encéfalo/patologia , Encéfalo/fisiopatologia , Mapeamento Encefálico , Feminino , Humanos , Masculino , Vias Neurais/fisiopatologia , Neuroimagem/métodos , Reprodutibilidade dos Testes , Adulto Jovem
13.
J Affect Disord ; 241: 371-380, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30145507

RESUMO

BACKGROUND: Major depressive disorder (MDD) and anxiety disorders are highly comorbid, sharing many similar symptoms, including impairments in cognitive control. Deficits in cognitive control could be a potential mechanism underlying impaired emotion regulation in mood disorders. METHODS: Participants were 44 individuals with no history of mental illness (healthy controls, HC), 31 individuals in the remitted state of MDD (rMDD), and 18 individuals who met lifetime DSM-IV-TR criteria for rMDD and an anxiety disorder in remission (Comorbid). Participants completed a Parametric Go/No-Go (PGNG) test during fMRI. Event-related analyses modeled activity for cognitive control successes (Hits for Targets, Rejections for Lures) and failures (Commissions on Lures) on the PGNG task. RESULTS: The rMDD group showed significantly reduced activity within the cognitive control network (CCN) during Commission errors, including the middle frontal gyrus and inferior parietal lobule (IPL). The Comorbid group showed significantly reduced activity in several clusters within the CCN during correct Rejections, including the left IPL and right inferior frontal gyrus and greater subgenual cingulate. Notably, during correct Rejections, 60% of activation for the Comorbid group was within the Salience and Emotion Network (SEN), with 0% within the CCN. LIMITATIONS: The size of the Comorbid subgroup was modest, preventing subanalysis of the different AD subtypes. CONCLUSIONS: There is evidence that CCN activity declines in rMDD and that there may be compensatory SEN activity in individuals with Comorbid rMDD and anxiety. Our findings support the identification of comorbid anxiety as a meaningful subtype of MDD that may obscure group differences between rMDD and HCs.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Cognição/fisiologia , Transtorno Depressivo Maior/fisiopatologia , Giro do Cíngulo/fisiologia , Adolescente , Mapeamento Encefálico , Comorbidade , Emoções/fisiologia , Função Executiva , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Adulto Jovem
14.
Front Psychiatry ; 9: 244, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29937738

RESUMO

There is substantial variability across studies of default mode network (DMN) connectivity in major depressive disorder, and reliability and time-invariance are not reported. This study evaluates whether DMN dysconnectivity in remitted depression (rMDD) is reliable over time and symptom-independent, and explores convergent relationships with cognitive features of depression. A longitudinal study was conducted with 82 young adults free of psychotropic medications (47 rMDD, 35 healthy controls) who completed clinical structured interviews, neuropsychological assessments, and 2 resting-state fMRI scans across 2 study sites. Functional connectivity analyses from bilateral posterior cingulate and anterior hippocampal formation seeds in DMN were conducted at both time points within a repeated-measures analysis of variance to compare groups and evaluate reliability of group-level connectivity findings. Eleven hyper- (from posterior cingulate) and 6 hypo- (from hippocampal formation) connectivity clusters in rMDD were obtained with moderate to adequate reliability in all but one cluster (ICC's range = 0.50 to 0.76 for 16 of 17). The significant clusters were reduced with a principle component analysis (5 components obtained) to explore these connectivity components, and were then correlated with cognitive features (rumination, cognitive control, learning and memory, and explicit emotion identification). At the exploratory level, for convergent validity, components consisting of posterior cingulate with cognitive control network hyperconnectivity in rMDD were related to cognitive control (inverse) and rumination (positive). Components consisting of anterior hippocampal formation with social emotional network and DMN hypoconnectivity were related to memory (inverse) and happy emotion identification (positive). Thus, time-invariant DMN connectivity differences exist early in the lifespan course of depression and are reliable. The nuanced results suggest a ventral within-network hypoconnectivity associated with poor memory and a dorsal cross-network hyperconnectivity linked to poorer cognitive control and elevated rumination. Study of early course remitted depression with attention to reliability and symptom independence could lead to more readily translatable clinical assessment tools for biomarkers.

15.
Curr Behav Neurosci Rep ; 5(1): 48-60, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29892518

RESUMO

Purpose of review: We set out to review the current state of science in neuroprediction, using biological measures of brain function, with task based fMRI to prospectively predict response to a variety of treatments. Recent findings: Task-based fMRI neuroprediction studies are balanced between whole brain and ROI specific analyses. The predominant tasks are emotion processing, with ROIs based upon amygdala and subgenual anterior cingulate gyrus, both within the salience and emotion network. A rapidly emerging new area of neuroprediction is of disease course and illness recurrence. Concerns include use of open-label and single arm studies, lack of consideration of placebo effects, unbalanced adjustments for multiple comparisons (over focus on type I error), small sample sizes, unreported effect sizes, overreliance on ROI studies. Summary: There is a need to adjust neuroprediction study reporting so that greater coherence can facilitate meta analyses, and increased funding for more multiarm studies in neuroprediction.

16.
Psychiatry Res Neuroimaging ; 275: 21-27, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29555382

RESUMO

We investigated the ability of preferred classical music to activate the nucleus accumbens in patients with Major depressive disorder (MDD). Twelve males with MDD and 10 never mentally ill male healthy controls (HC) completed measures of anhedonia and depression severity, and listened to 90-second segments of preferred classical music during fMRI. Compared to HCs, individuals with MDD showed less activation of the left nucleus accumbens (NAcc). Individuals with MDD showed attenuation of the left NAcc response in later compared to earlier parts of the experiment, supporting theories that MDD involves an inability to sustain reward network activation. Counter intuitively, we found that NAcc activity during early music listening was associated with greater depression severity. In whole-brain analyses, anhedonia scores predicted activity in regions within the default mode network, supporting previous findings. Our results support theories that MDD involves an inability to sustain reward network activation. It also highlights that pleasant classical music can engage critical neural reward circuitry in MDD.


Assuntos
Anedonia/fisiologia , Percepção Auditiva/fisiologia , Transtorno Depressivo Maior/fisiopatologia , Neuroimagem Funcional/métodos , Música , Núcleo Accumbens/fisiopatologia , Adolescente , Adulto , Transtorno Depressivo Maior/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Núcleo Accumbens/diagnóstico por imagem , Adulto Jovem
17.
J Affect Disord ; 227: 183-191, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29100150

RESUMO

BACKGROUND: Major depressive disorder (MDD) is characterized by dysfunction in cognitive and emotional systems. However, the neural network correlates of cognitive control (cold cognition) and emotion processing (hot cognition) during the remitted state of MDD (rMDD) remain unclear and not fully probed, which has important implications for identifying intermediate phenotypes of depression risk. METHODS: 43 young adults with rMDD and 33 healthy controls (HCs) underwent fMRI while completing separate tasks of cold cognition (Parametric Go/No-Go test) and hot cognition (Facial Emotion Processing Test). Two 2 group (rMDD, HC) × 2 event (sad/fearful faces, correct rejections) factorial models of activation were calculated in SPM8. Functional activation was evaluated in the salience and emotional network (SEN) and the cognitive control network (CCN), including hypothesized interaction between group and task within the CCN. RESULTS: Individuals with rMDD demonstrated greater spatial extent of suprathreshold activation within the SEN during sad faces relative to HCs. There were several regions within the CCN in which HCs showed greater activation than rMDD during correct rejections of lures, whereas individuals with rMDD showed greater activation than HCs during sad or fearful faces. LIMITATIONS: Results were not directly compared with active MDD. CONCLUSIONS: These results provide evidence of deficient CCN engagement during cognitive control in rMDD (dysfunctional cold cognition). Elevated SEN activation during sad faces could represent heightened salience of negative emotional faces in rMDD; elevated CCN activation during emotional faces in rMDD could represent compensatory regulatory control. These group differences may represent vulnerability factors, scars of prior depressive episodes, or processes maintaining wellness.


Assuntos
Cognição/fisiologia , Transtorno Depressivo Maior/fisiopatologia , Emoções/fisiologia , Mapeamento Encefálico , Estudos de Casos e Controles , Expressão Facial , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Estimulação Luminosa , Indução de Remissão , Adulto Jovem
18.
Hum Brain Mapp ; 39(1): 232-248, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28990258

RESUMO

Occurring in at least 1 in 3,000 live births, chromosome 22q11.2 deletion syndrome (22q11DS) produces a complex phenotype that includes a constellation of medical complications such as congenital cardiac defects, immune deficiency, velopharyngeal dysfunction, and characteristic facial dysmorphic features. There is also an increased incidence of psychiatric diagnosis, especially intellectual disability and ADHD in childhood, lifelong anxiety, and a strikingly high rate of schizophrenia spectrum disorders, which occur in around 30% of adults with 22q11DS. Using innovative computational connectomics, we studied how 22q11DS affects high-level network signatures of hierarchical modularity and its intrinsic geometry in 55 children with confirmed 22q11DS and 27 Typically Developing (TD) children. Results identified 3 subgroups within our 22q11DS sample using a K-means clustering approach based on several midline structural measures-of-interests. Each subgroup exhibited distinct patterns of connectome abnormalities. Subtype 1, containing individuals with generally healthy-looking brains, exhibited no significant differences in either modularity or intrinsic geometry when compared with TD. By contrast, the more anomalous 22q11DS Subtypes 2 and 3 brains revealed significant modular differences in the right hemisphere, while Subtype 3 (the most anomalous anatomy) further exhibited significantly abnormal connectome intrinsic geometry in the form of left-right temporal disintegration. Taken together, our findings supported an overall picture of (a) anterior-posteriorly differential interlobar frontotemporal/frontoparietal dysconnectivity in Subtypes 2 and 3 and (b) differential intralobar dysconnectivity in Subtype 3. Our ongoing studies are focusing on whether these subtypes and their connnectome signatures might be valid biomarkers for predicting the degree of psychosis-proneness risk found in 22q11DS. Hum Brain Mapp 39:232-248, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Encéfalo/fisiopatologia , Conectoma , Síndrome de DiGeorge/fisiopatologia , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Criança , Análise por Conglomerados , Conectoma/métodos , Síndrome de DiGeorge/diagnóstico por imagem , Feminino , Lateralidade Funcional , Humanos , Estudos Longitudinais , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia
19.
J Clin Exp Neuropsychol ; 40(1): 84-94, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28562181

RESUMO

OBJECTIVE: The recent dramatic increase in research investigating auditory verbal hallucinations (AVHs) has broadened the former narrow focus on schizophrenia to incorporate additional populations that experience these symptoms. However, an understanding of potential shared mechanisms remains elusive. Based on theories suggesting a failure of top-down cognitive control, we aimed to compare the relationship between AVHs and cognition in two categorical diagnoses of psychosis, schizophrenia and psychotic bipolar disorder. METHOD: A total of 124 adults aged 21-60 participated, of whom 76 had present-state psychosis (schizophrenia, n = 53; bipolar disorder with psychosis, n = 23), and 48 were non-clinical controls. Diagnosis and hallucination presence was determined using the Structured Clinical Diagnostic Interview for DSM-IV TR. AVHs severity was assessed using the Positive and Negative Syndrome Scale. Participants also completed the MATRICS cognitive battery. RESULTS: The bipolar disorder with psychosis group performed better than the schizophrenia group for cognitive domains of Processing speed, Attention, Working memory (WM), and Visual memory. Hierarchical binary logistic regression found that WM significantly predicted presence of AVHs in both psychotic groups, but diagnosis did not significantly increase the predictive value of the model. A hierarchical multiple linear regression found that schizophrenia diagnosis was the only significant predictor of hallucination severity. CONCLUSIONS: The findings of this study-the first, to our knowledge, to compare the relationship between AVHs and MATRICS domains across schizophrenia and bipolar disorder with psychosis-support theories that deficits in WM underly the genesis of AVHs. WM potentially represents a shared mechanism of AVHs across diagnoses, supporting dimensional classifications of these psychotic disorders. However, non-cognitive factors predictive of hallucination severity may be specific to schizophrenia.


Assuntos
Transtorno Bipolar/diagnóstico , Alucinações/diagnóstico , Alucinações/psicologia , Memória de Curto Prazo , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto , Atenção , Transtorno Bipolar/psicologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Psicometria
20.
J Neuropsychol ; 12(1): 120-141, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27580877

RESUMO

We aimed to elicit emotion in patients with surgically circumscribed lesions of the prefrontal cortex (PFC) in order to elucidate the precise functional roles in emotion processing of the discrete subregions comprising the ventromedial PFC, including the medial PFC and orbitofrontal cortex (OFC). Three components of emotional reactivity were measured: subjective experience, behaviour, and physiological response. These included measures of self-reported emotion, observer-rated facial expression of emotion and measurements of heart rate and heart rate variability (HRV) during film viewing, and a measure of subjective emotional change since surgery. Patients with lesions to the ventromedial PFC demonstrated significant differences compared with controls in HRV during the film clips, suggesting a shift to greater dominance of sympathetic input. In contrast, patients with lesions restricted to the OFC showed significant differences in HRV suggesting reduced sympathetic input. They also showed less facial expression of emotion during positive film clips, and reported more subjective emotional change since surgery compared with controls. This human lesion study is important for refining theoretical models of emotion processing by the ventromedial PFC, which until now have primarily been based on anatomical connectivity, animal lesion, and human functional neuroimaging research. Such theories have implications for the treatment of a wide variety of emotional disorders.


Assuntos
Mapeamento Encefálico , Emoções/fisiologia , Frequência Cardíaca/fisiologia , Córtex Pré-Frontal/fisiopatologia , Córtex Pré-Frontal/cirurgia , Adulto , Estudos de Casos e Controles , Expressão Facial , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/diagnóstico por imagem , Autorrelato
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