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1.
Hum Brain Mapp ; 40(12): 3415-3430, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31033120

RESUMO

Patients with epilepsy are often able to predict seizure occurrence subsequent to an acute stress experience. However, neuroimaging investigations into the neural basis of this relationship or the potential influence of perceived life stress are limited. The current study assessed the relationship between perceived stress and the neurobehavioral response to stress in patients with left temporal lobe epilepsy (LTLE) and healthy controls (HCs) using heart rate, salivary cortisol level, and functional magnetic resonance imaging and compared these effects between HCs and LTLE. Matched on perceived stress levels, groups of 36 patients with LTLE and 36 HCs completed the Montreal Imaging Stress Task, with control and stress math task conditions. Among LTLEs, 27 reported that prior (acute) stress affected their seizures (LTLES+), while nine did not (LTLES-). The results revealed that increased perceived stress was associated with seizure frequency in LTLE. Further, cortisol secretion was greater in LTLE, but did not vary with perceived stress as observed in HCs. A linear mixed-effects analysis revealed that as perceived stress increased, activation in the hippocampal complex (parahippocampal gyrus and hippocampus) decreased during stressful math in the LTLES+, increased in HCs, but did not vary in the LTLES-. Task-based functional connectivity analyses revealed LTLE differences in hippocampal functional connectivity with sensory cortex specific to stressor modalities. We argue that the current study demonstrates an inhibitory hippocampal mechanism underlying differences in resilience to stress between HCs and LTLE, as well as LTLE patients who report stress as a precipitant of seizures.

2.
Bipolar Disord ; 21(6): 503-513, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31025452

RESUMO

OBJECTIVES: Bipolar disorder is marked by progressive symptomatic changes, which have been linked with episode-related structural findings-particularly in the prefrontal cortex. However, few studies have examined neurofunctional and neurochemical effects of disease burden. In this study, we compared first- and multi-episode bipolar individuals. We hypothesized that the latter would demonstrate evidence of neurophysiological differences consistent with a model of progressive functional degradation of these networks. METHODS: First- and multi-episode manic bipolar subjects participated in functional magnetic resonance imaging (fMRI) including a continuous performance task with emotional distractors, and in single-voxel (1 H) magnetic resonance spectroscopy (MRS). A priori fMRI regions-of-interest (ROI) included structures comprising prefrontal-striatal-amygdala networks; (1 H)MRS voxels were placed within bilateral ventrolateral prefrontal (VLPFC) and anterior cingulate cortex (ACC). Both ROI and voxel-based brain activation in response to emotional stimuli, and neurochemical concentrations derived from (1 H)MRS were compared across bipolar groups. RESULTS: Multi-episode bipolar subjects showed relatively lower regional activation across prefrontal-striatal-amygdala networks, including bilateral VLPFC, orbitofrontal cortex, ACC, putamen, caudate, and amygdala. Exploratory whole-brain, voxel-based analysis suggested additional areas of lower activation extending into Brodmann area 22, posterior parietal regions, and right thalamus. Glutamate and N-acetylaspartate (NAA) concentrations were also relatively lower in the ACC of multi-episode subjects. CONCLUSIONS: Disease burden, exemplified by multiple affective episodes is associated with evidence of widespread decrements in affective network activity. Lower ACC NAA concentration is similarly consistent with a model of progressive functional deficits. These findings support the functional significance of previously observed progressive structural changes throughout these regions.

3.
Psychiatry Res Neuroimaging ; 286: 53-59, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30903953

RESUMO

We examined the effects of lisdexamfetamine (LDX) treatment on ventral prefrontal cortex (VPFC) and striatal brain activation in binge eating disorder (BED). We hypothesized that participants with BED have an abnormal brain response to palatable food cues, and that VPFC and striatal regions would respond to such cues after LDX treatment. Twenty women with moderate to severe BED consented to a 12-week, open-label trial of LDX with fMRI before and after treatment. Twenty obese women without BED served as healthy controls and received one fMRI. LDX was started at 30 mg/d with a target of 70 mg/d at week 12. At baseline, women with BED showed greater activation in ventrolateral prefrontal cortex (VLPFC), striatum, and globus pallidus to food pictures and brain activation to food pictures predicted clinical outcome at 12 weeks. After 12 weeks of LDX treatment, BED women showed significant reductions in globus pallidus activation. Reductions in ventromedial prefrontal cortex (VMPFC) and thalamus activation specifically correlated with binge eating and obsessive-compulsive symptom reductions, respectively. Results suggest that BED is characterized by an abnormally large VPFC-subcortical brain response to palatable foods that LDX treatment helps modify. Moreover, VPFC-subcortical activation at baseline is a potential biomarker of LDX response.

4.
J Affect Disord ; 234: 14-19, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29522938

RESUMO

BACKGROUND: The neurophysiological substrates of cognition and emotion, as seen with fMRI, are generally explained using modular structures. The present study was designed to probe the modular structure of cognitive-emotional processing in bipolar and healthy individuals using factor analysis and compare the results with current conceptions of the neurophysiology of bipolar disorder. METHODS: Exploratory factor analysis was used to assess patterns of covariation among brain regions-of-interest activated during the Continuous Performance Task with Emotional and Neutral Distractors in healthy and bipolar individuals without a priori constraints on the number or composition of latent factors. RESULTS: Results indicated a common cognitive-emotional network consisting of prefrontal, medial temporal, limbic, parietal, anterior cingulate and posterior cingulate modules. However, reduced brain activation to emotional stimuli in the frontal, medial temporal and limbic modules was apparent in the bipolar relative to the healthy group, potentially accounting for emotional dysregulation in bipolar disorder. LIMITATIONS: This study is limited by a relatively small sample size recruited at a single site. The results have yet to be validated on a larger independent sample. CONCLUSIONS: Although the modular structure of cognitive-emotional processing is similar in bipolar and healthy individuals, activation in response to emotional/neutral cues varies. These findings are not only consistent with recent conceptions of mood regulation in bipolar disorder, but also suggest that regional activation can be considered within tighter modular structures without compromising data interpretation. This demonstration may serve as a template for data reduction in future region-of-interest analyses to increase statistical power.


Assuntos
Transtorno Bipolar/fisiopatologia , Encéfalo/fisiopatologia , Cognição/fisiologia , Emoções/fisiologia , Adulto , Afeto , Mapeamento Encefálico , Análise Fatorial , Feminino , Voluntários Saudáveis , Humanos , Imagem por Ressonância Magnética , Masculino , Adulto Jovem
5.
Mov Disord ; 33(1): 136-145, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29124784

RESUMO

OBJECTIVE: We sought to determine whether abnormalities in emotion processing underlie functional (psychogenic) dystonia, one of the most common functional movement disorders. METHODS: Motor and emotion circuits were examined in 12 participants with functional dystonia, 12 with primary organic dystonia, and 25 healthy controls using functional magnetic resonance imaging at 4T and a finger-tapping task (motor task), a basic emotion-recognition task (emotional faces task), and an intense-emotion stimuli task. RESULTS: There were no differences in motor task activation between groups. In the faces task, when compared with the other groups, functional dystonia patients showed areas of decreased activation in the right middle temporal gyrus and bilateral precuneus and increased activation in the right inferior frontal gyrus, bilateral occipital cortex and fusiform gyrus, and bilateral cerebellum. In the intense-emotion task, when compared with the other groups, functional dystonia patients showed decreased activation in the left insular and left motor cortices (compared to organic dystonia, they showed an additional decrease in activation in the right opercular cortex and right motor cortex) and increased activation in the left fusiform gyrus. CONCLUSIONS: Functional dystonia patients exhibited stimulus-dependent altered activation in networks involved in motor preparation and execution, spatial cognition, and attentional control. These results support the presence of network dysfunction in functional dystonia. © 2017 International Parkinson and Movement Disorder Society.

6.
Neuroimage Clin ; 17: 179-187, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29085776

RESUMO

BACKGROUND: Despite its high prevalence and associated disability, the neural correlates of emotion processing in patients with functional (psychogenic) tremor (FT), the most common functional movement disorder, remain poorly understood. METHODS: In this cross sectional functional magnetic resonance imaging (fMRI) study at 4T, 27 subjects with FT, 16 with essential tremor (ET), and 25 healthy controls (HCs) underwent a finger-tapping motor task, a basic-emotion task, and an intense-emotion task to probe motor and emotion circuitries. Anatomical and functional MRI data were processed with FSL (FMRIB Software Library) and AFNI (Analysis of Functional Neuroimages), followed by seed-to-seed connectivity analyses using anatomical regions defined from the Harvard-Oxford subcortical atlas; all analyses were corrected for multiple comparisons. RESULTS: After controlling for depression scores and correcting for multiple comparisons, the FT group showed increased activation in the right cerebellum compared to ET during the motor task; and increased activation in the paracingulate gyrus and left Heschl's gyrus compared with HC with decreased activation in the right precentral gyrus compared with ET during the basic-emotion task. No significant differences were found after adjusting for multiple comparisons during the intense-emotion task but increase in connectivity between the left amygdala and left middle frontal gyrus survived corrections in the FT subjects during this task, compared to HC. CONCLUSIONS: In response to emotional stimuli, functional tremor is associated with alterations in activation and functional connectivity in networks involved in emotion processing and theory of mind. These findings may be relevant to the pathophysiology of functional movement disorders.


Assuntos
Encéfalo/fisiopatologia , Emoções/fisiologia , Tremor/fisiopatologia , Adulto , Idoso , Mapeamento Encefálico , Cerebelo/fisiopatologia , Estudos Transversais , Expressão Facial , Reconhecimento Facial/fisiologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Atividade Motora , Vias Neurais/fisiopatologia
7.
Nutr Neurosci ; 21(4): 297-305, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28221821

RESUMO

OBJECTIVES: Preclinical studies have shown that blueberry supplementation can improve cognitive performance and neural function in aged animals and have identified associations between anthocyanins and such benefits. Preliminary human trials also suggest cognitive improvement in older adults, although direct evidence of enhancement of brain function has not been demonstrated. In this study, we investigated the effect of blueberry supplementation on regional brain activation in older adults at risk for dementia. METHODS: In a randomized, double-blind, placebo-controlled trial we performed pre- and post-intervention functional magnetic resonance imaging during a working memory (WM) task to assess the effect of blueberry supplementation on blood oxygen level-dependent (BOLD) signal in older adults with mild cognitive impairment, a risk condition for dementia. RESULTS: Following daily supplementation for 16 weeks, blueberry-treated participants exhibited increased BOLD activation in the left pre-central gyrus, left middle frontal gyrus, and left inferior parietal lobe during WM load conditions (corrected P < 0.01). There was no clear indication of WM enhancement associated with blueberry supplementation. Diet records indicated no between-group difference in anthocyanin consumption external to the intervention. DISCUSSION: These data demonstrate, for the first time, enhanced neural response during WM challenge in blueberry-treated older adults with cognitive decline and are consistent with prior trials showing neurocognitive benefit with blueberry supplementation in this at-risk population.


Assuntos
Mirtilos Azuis (Planta)/química , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/dietoterapia , Idoso , Idoso de 80 Anos ou mais , Antocianinas/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Disfunção Cognitiva/diagnóstico por imagem , Demência , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/efeitos dos fármacos , Frutas , Humanos , Imagem por Ressonância Magnética , Masculino , Memória de Curto Prazo , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/efeitos dos fármacos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/efeitos dos fármacos
8.
Bipolar Disord ; 19(4): 259-272, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28574156

RESUMO

OBJECTIVES: Individualized treatment for bipolar disorder based on neuroimaging treatment targets remains elusive. To address this shortcoming, we developed a linguistic machine learning system based on a cascading genetic fuzzy tree (GFT) design called the LITHium Intelligent Agent (LITHIA). Using multiple objectively defined functional magnetic resonance imaging (fMRI) and proton magnetic resonance spectroscopy (1 H-MRS) inputs, we tested whether LITHIA could accurately predict the lithium response in participants with first-episode bipolar mania. METHODS: We identified 20 subjects with first-episode bipolar mania who received an adequate trial of lithium over 8 weeks and both fMRI and 1 H-MRS scans at baseline pre-treatment. We trained LITHIA using 18 1 H-MRS and 90 fMRI inputs over four training runs to classify treatment response and predict symptom reductions. Each training run contained a randomly selected 80% of the total sample and was followed by a 20% validation run. Over a different randomly selected distribution of the sample, we then compared LITHIA to eight common classification methods. RESULTS: LITHIA demonstrated nearly perfect classification accuracy and was able to predict post-treatment symptom reductions at 8 weeks with at least 88% accuracy in training and 80% accuracy in validation. Moreover, LITHIA exceeded the predictive capacity of the eight comparator methods and showed little tendency towards overfitting. CONCLUSIONS: The results provided proof-of-concept that a novel GFT is capable of providing control to a multidimensional bioinformatics problem-namely, prediction of the lithium response-in a pilot data set. Future work on this, and similar machine learning systems, could help assign psychiatric treatments more efficiently, thereby optimizing outcomes and limiting unnecessary treatment.


Assuntos
Sintomas Comportamentais , Transtorno Bipolar , Resistência a Medicamentos , Compostos de Lítio , Imagem por Ressonância Magnética/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Adolescente , Adulto , Antimaníacos/administração & dosagem , Antimaníacos/efeitos adversos , Inteligência Artificial , Sintomas Comportamentais/diagnóstico , Sintomas Comportamentais/tratamento farmacológico , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/psicologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Monitoramento de Medicamentos/métodos , Feminino , Lógica Fuzzy , Humanos , Compostos de Lítio/administração & dosagem , Compostos de Lítio/efeitos adversos , Masculino , Imagem Multimodal/métodos , Projetos Piloto , Valor Preditivo dos Testes , Prognóstico
9.
J Affect Disord ; 209: 246-253, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27936454

RESUMO

BACKGROUND: Studying youth at high risk of developing bipolar disorder may clarify neurobiological factors associated with vulnerability to this illness. We present here a baseline characterization of brain structure in youth at-risk for bipolar disorder. METHODS: Magnetic resonance images were obtained from 115 child and adolescent offspring of bipolar disorder type I subjects and 57 healthy child and adolescent offspring of healthy parents (healthy control offspring). Offspring of parents with bipolar disorder were divided into healthy bipolar offspring (n=47) or symptomatic bipolar offspring (n=68), according to presence or absence of childhood-onset psychopathology. All bipolar offspring were free of major mood and psychotic disorders. Gray (GM) and white matter (WM) volumes were compared between groups using voxel-based morphometry. RESULTS: No differences in GM volumes were found across groups. Healthy bipolar offspring presented with decreased WM volumes in areas of the right frontal, temporal and parietal lobes, and in the left temporal and parietal lobes compared to healthy control offspring. Symptomatic bipolar offspring did not present with any differences in WM volumes compared to either healthy bipolar offspring or healthy control offspring. LIMITATIONS: Cross-sectional design and heterogeneous sample of symptomatic bipolar offspring. CONCLUSIONS: WM volume decreases in areas of the frontal, occipital, and parietal lobes are present in bipolar offspring prior to the development of any psychiatric symptoms, and may be a correlate of familial risk to bipolar disorder. In this large cohort, we have not found evidence for regional GM volume abnormalities as an endophenotype for bipolar disorder.


Assuntos
Transtorno Bipolar , Encéfalo/diagnóstico por imagem , Filho de Pais Incapacitados , Pais , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Transtorno Bipolar/diagnóstico , Criança , Estudos Transversais , Endofenótipos , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Tamanho do Órgão/fisiologia
10.
J Am Acad Child Adolesc Psychiatry ; 55(11): 980-989, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27806866

RESUMO

OBJECTIVE: To examine prefrontal and amygdala activation during emotional processing in youth with or at varying risk for developing mania to identify candidate central prodromal risk biomarkers. METHOD: Four groups of medication-free adolescents (10-20 years old) participated: adolescents with first-episode bipolar I disorder (BP-I; n = 32), adolescents with a parent with bipolar disorder and a depressive disorder (at-risk depressed [ARD]; n = 32), healthy adolescents with a parent with bipolar disorder (at-risk healthy [ARH]; n = 32), and healthy adolescents with no personal or family history of psychiatric illness (healthy comparison [HC]; n = 32). Participants underwent functional magnetic resonance imaging while performing a continuous performance task with emotional and neutral distracters. Region-of-interest analyses were performed for the bilateral amygdala and for subregions of the ventrolateral prefrontal cortex and anterior cingulate cortex. RESULTS: Overall, no group differences in bilateral amygdala and ventrolateral prefrontal cortex (Brodmann area [BA] 45/47) activation during emotional or neutral stimuli were observed. The BP-I group exhibited lower right pregenual anterior cingulate cortex activation compared with the HC group, and activation in the left BA 44 was greater in the ARH and ARD groups compared with the HC group. BP-I and ARD groups exhibited blunted activation in the right BA 10 compared with the ARH group. CONCLUSION: During emotional processing, amygdala and ventrolateral prefrontal cortex (BA 45/47) activation does not differ in youth with or at increasing risk for BP-I. However, blunted pregenual anterior cingulate cortex activation in first-episode mania could represent an illness biomarker, and greater prefrontal BA 10 and BA 44 activations in at-risk youth could represent a biomarker of risk or resilience warranting additional investigation in prospective longitudinal studies.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Transtorno Bipolar/fisiopatologia , Filho de Pais Incapacitados , Córtex Pré-Frontal/fisiopatologia , Adolescente , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Transtorno Bipolar/diagnóstico por imagem , Criança , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Risco , Adulto Jovem
11.
Bipolar Disord ; 18(6): 490-501, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27647671

RESUMO

OBJECTIVES: We tested the hypothesis that, with treatment, functional magnetic resonance imaging (fMRI) regional brain activation in first-episode mania would normalize - i.e., that differences from healthy subjects would diminish over time, and would be associated with clinical remission status, potentially identifying neuroanatomic treatment response markers. METHODS: Forty-two participants with bipolar I disorder were recruited during their first manic episode, pseudo-randomized to open-label lithium or quetiapine, and followed for 8 weeks. fMRI scans were obtained at baseline and then after 1 and 8 weeks of treatment, while participants performed a continuous performance task with emotional distracters. Healthy participants received fMRI scans at these same intervals. Specific region-of-interest (ROI) activations within prefrontal emotional networks were assessed as potential measures of treatment response. RESULTS: ROI data were reduced using exploratory factor analysis, which identified five factors that were organizationally consistent with functional anatomic models of human emotion modulation. Half of the participants with bipolar disorder achieved remission by Week 8 and were contrasted with the other half that did not. Analyses demonstrated that, in the bipolar disorder group in general, treatment led to decreases in activation across brain regions toward healthy subject values. However, differences in activation changes were observed between subjects with bipolar disorder who did or did not achieve remission in subcortical and amygdala factors. CONCLUSIONS: These findings provide evidence for potential neuroanatomic treatment response markers in first-episode bipolar disorder.


Assuntos
Tonsila do Cerebelo , Transtorno Bipolar , Lítio/uso terapêutico , Imagem por Ressonância Magnética/métodos , Fumarato de Quetiapina/uso terapêutico , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Antimaníacos/uso terapêutico , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Transtorno Bipolar/terapia , Emoções/fisiologia , Cuidado Periódico , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Análise e Desempenho de Tarefas , Resultado do Tratamento
12.
J Child Adolesc Psychopharmacol ; 26(4): 372-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26783833

RESUMO

OBJECTIVE: We sought to evaluate the neurophysiology of mindfulness-based cognitive therapy for children (MBCT-C) in youth with generalized, social, and/or separation anxiety disorder who were at risk for developing bipolar disorder. METHODS: Nine youth (mean age: 13 ± 2 years) with a generalized, social, and/or separation anxiety disorder and a parent with bipolar disorder completed functional magnetic resonance imaging (fMRI) while performing a continuous processing task with emotional and neutral distractors (CPT-END) prior to and following 12 weeks of MBCT-C. RESULTS: MBCT-C was associated with increases in activation of the bilateral insula, lentiform nucleus, and thalamus, as well as the left anterior cingulate while viewing emotional stimuli during the CPT-END, and decreases in anxiety were correlated with change in activation in the bilateral insula and anterior cingulate during the viewing of emotional stimuli (p < 0.05, uncorrected; p < 0.005 corrected; cluster size, 37 voxels). CONCLUSIONS: MBCT-C treatment in anxious youth with a familial history of bipolar disorder is associated with increased activation of brain structures that subserve interoception and the processing of internal stimuli-functions that are ostensibly improved by this treatment.


Assuntos
Transtornos de Ansiedade/terapia , Transtorno Bipolar/prevenção & controle , Terapia Cognitivo-Comportamental/métodos , Atenção Plena/métodos , Adolescente , Transtornos de Ansiedade/psicologia , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Fatores de Risco , Resultado do Tratamento
13.
J Clin Exp Neuropsychol ; 37(6): 563-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26059389

RESUMO

INTRODUCTION: Previous research has shown that performance on cognitive tasks administered in the scanner can be altered by the scanner environment. There are no previous studies that have investigated the impact of scanner noise using a well-validated measure of affective change. The goal of this study was to determine whether performance on an affective attentional task or emotional response to the task would change in the presence of distracting acoustic noise, such as that encountered in a magnetic resonance imaging (MRI) environment. METHOD: Thirty-four young adults with no self-reported history of neurologic disorder or mental illness completed three blocks of the affective Posner task outside of the scanner. The task was meant to induce frustration through monetary contingencies and rigged feedback. Participants completed a Self-Assessment Manikin at the end of each block to rate their mood, arousal level, and sense of dominance. During the task, half of the participants heard noise (recorded from a 4T MRI system), and half heard no noise. RESULTS: The affective Posner task led to significant reductions in mood and increases in arousal in healthy participants. The presence of scanner noise did not impact task performance; however, individuals in the noise group did report significantly poorer mood throughout the task. CONCLUSIONS: The results of the present study suggest that the acoustic qualities of MRI enhance frustration effects on an affective attentional task and that scanner noise may influence mood during similar functional magnetic resonance imaging (fMRI) tasks.


Assuntos
Afeto/fisiologia , Atenção/fisiologia , Neuroimagem Funcional/normas , Imagem por Ressonância Magnética/efeitos adversos , Ruído/efeitos adversos , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
14.
J Affect Disord ; 175: 251-5, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25658500

RESUMO

OBJECTIVES: To identify abnormalities in high energy phosphate cerebral metabolism in euthymic bipolar disorder. METHODS: Phosphorus-31 magnetic resonance spectroscopic imaging ((31)P MRSI) data were acquired from the entire brain of 9 euthymic adults with bipolar disorder and 13 healthy adults. Estimates of phosphocreatine (PCr) and adenosine triphosphate (ATP) in homogeneous gray and white matter were obtained by tissue regression analysis. RESULTS: Analyses of covariance revealed the effect of age to be significantly different between bipolar and healthy groups for concentrations of PCr (p=0.0018) and ATP (p=0.013) in gray matter. These metabolites were negatively correlated with age in gray matter in bipolar subjects while PCr was positively correlated with age in gray matter of healthy subjects. Additionally, age-corrected concentrations of PCr in gray matter were significantly elevated in bipolar subjects (p=0.0048). LIMITATIONS: Given that this cross-sectional study possessed a small sample and potentially confounding effects of medication status, we recommend a larger, longitudinal study to more robustly study relationships between bioenergetic impairment and duration of disease. CONCLUSIONS: Our results suggest bioenergetic impairment related to mitochondrial function may be progressive in multi-episode bipolar subjects as they age.


Assuntos
Envelhecimento/metabolismo , Transtorno Bipolar/metabolismo , Córtex Cerebral/metabolismo , Substância Cinzenta/metabolismo , Fosfatos/metabolismo , Fósforo/análise , Trifosfato de Adenosina/metabolismo , Adulto , Transtorno Bipolar/tratamento farmacológico , Estudos Transversais , Feminino , Humanos , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fosfocreatina/metabolismo , Substância Branca/metabolismo
15.
Alcohol Clin Exp Res ; 39(2): 272-81, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25684049

RESUMO

BACKGROUND: Alcohol dependence (AD) has global effects on brain structure and function, including frontolimbic regions regulating affective processing. Preliminary evidence suggests alcohol blunts limbic response to negative affective stimuli and increases activation to positive affective stimuli. Subtle gender differences are also evident during affective processing. METHODS: Fourteen abstinent AD individuals (8 F, 6 M) and 14 healthy controls (9 F, 5 M), ages 23 to 60, were included in this facial affective processing functional magnetic resonance imaging pilot study. Whole-brain linear regression analyses were performed, and follow-up analyses examined whether AD status significantly predicted depressive symptoms and/or coping. RESULTS: Fearful Condition-The AD group demonstrated reduced activation in the right medial frontal gyrus, compared with controls. Gender moderated the effects of AD in bilateral inferior frontal gyri. Happy Condition-AD individuals had increased activation in the right thalamus. Gender moderated the effects of AD in the left caudate, right middle frontal gyrus, left paracentral lobule, and right lingual gyrus. Interactive AD and gender effects for fearful and happy faces were such that AD men activated more than control men, but AD women activated less than control women. Enhanced coping was associated with greater activation in right medial frontal gyrus during fearful condition in AD individuals. CONCLUSIONS: Abnormal affective processing in AD may be a marker of alcoholism risk or a consequence of chronic alcoholism. Subtle gender differences were observed, and gender moderated the effects of AD on neural substrates of affective processing. AD individuals with enhanced coping had brain activation patterns more similar to controls. Results help elucidate the effects of alcohol, gender, and their interaction on affective processing.


Assuntos
Alcoolismo/fisiopatologia , Encéfalo/fisiopatologia , Depressão/fisiopatologia , Emoções/fisiologia , Adaptação Psicológica , Adulto , Alcoolismo/psicologia , Estudos de Casos e Controles , Núcleo Caudado/fisiopatologia , Depressão/psicologia , Expressão Facial , Feminino , Neuroimagem Funcional , Humanos , Modelos Lineares , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Occipital/fisiopatologia , Lobo Parietal/fisiopatologia , Projetos Piloto , Córtex Pré-Frontal/fisiopatologia , Fatores Sexuais , Percepção Social , Adulto Jovem
16.
Neurology ; 84(8): 794-802, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25632091

RESUMO

OBJECTIVE: To examine the effect of cost, a traditionally "inactive" trait of intervention, as contributor to the response to therapeutic interventions. METHODS: We conducted a prospective double-blind study in 12 patients with moderate to severe Parkinson disease and motor fluctuations (mean age 62.4 ± 7.9 years; mean disease duration 11 ± 6 years) who were randomized to a "cheap" or "expensive" subcutaneous "novel injectable dopamine agonist" placebo (normal saline). Patients were crossed over to the alternate arm approximately 4 hours later. Blinded motor assessments in the "practically defined off" state, before and after each intervention, included the Unified Parkinson's Disease Rating Scale motor subscale, the Purdue Pegboard Test, and a tapping task. Measurements of brain activity were performed using a feedback-based visual-motor associative learning functional MRI task. Order effect was examined using stratified analysis. RESULTS: Although both placebos improved motor function, benefit was greater when patients were randomized first to expensive placebo, with a magnitude halfway between that of cheap placebo and levodopa. Brain activation was greater upon first-given cheap but not upon first-given expensive placebo or by levodopa. Regardless of order of administration, only cheap placebo increased activation in the left lateral sensorimotor cortex and other regions. CONCLUSION: Expensive placebo significantly improved motor function and decreased brain activation in a direction and magnitude comparable to, albeit less than, levodopa. Perceptions of cost are capable of altering the placebo response in clinical studies. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that perception of cost is capable of influencing motor function and brain activation in Parkinson disease.


Assuntos
Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/economia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/economia , Efeito Placebo , Idoso , Efeitos Psicossociais da Doença , Estudos Cross-Over , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/economia , Método Duplo-Cego , Feminino , Humanos , Injeções Subcutâneas , Levodopa/administração & dosagem , Levodopa/economia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/psicologia , Estudos Prospectivos , Resultado do Tratamento
17.
J Affect Disord ; 171: 54-9, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25285899

RESUMO

BACKGROUND: Depressive and anxiety disorders are among the most frequently occurring psychiatric conditions in children and adolescents and commonly present occur together. Co-occurring depression and anxiety is associated with increased functional impairment and suicidality compared to depression alone. Despite this, little is known regarding the neurostructural differences between anxiety disorders and major depressive disorder (MDD). Moreover, the neurophysiologic impact of the presence of anxiety in adolescents with MDD is unknown. METHODS: Using voxel-based morphometry, gray matter volumes were compared among adolescents with MDD (and no co-morbid anxiety disorders, n=14), adolescents with MDD and co-morbid anxiety ("anxious depression," n=12), and healthy comparison subjects (n=41). RESULTS: Patients with anxious depression exhibited decreased gray matter volumes in the dorsolateral prefrontal cortex (DLPFC) compared to patients with MDD alone. Compared to healthy subjects, adolescents with anxious depression had increased gray matter volumes in the pre- and post-central gyri. LIMITATIONS: The current sample size was small and precluded an analysis of multiple covariates which may influence GMV. CONCLUSIONS: Gray matter deficits in the DLPFC in youth with anxious depression compared to patients with MDD and no co-occurring anxiety may reflect the more severe psychopathology in these patients. Additionally, the distinct gray matter fingerprints of MDD and anxious depression (compared to healthy subjects) suggest differing neurophysiologic substrates for these conditions, though the etiology and longitudinal trajectory of the differences remain to be determined.


Assuntos
Transtornos de Ansiedade/complicações , Transtornos de Ansiedade/patologia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/patologia , Substância Cinzenta/patologia , Imagem por Ressonância Magnética/métodos , Adolescente , Mapeamento Encefálico/métodos , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Tamanho do Órgão , Pediatria/métodos , Córtex Pré-Frontal/patologia
18.
J Anxiety Disord ; 28(7): 717-23, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25155256

RESUMO

BACKGROUND: It is established that pediatric patients with generalized anxiety disorder (GAD) exhibit functional abnormalities and altered gray matter volumes in neural structures that subserve emotional processing, yet there are no data regarding the surface anatomy of the cerebral cortex in youth with GAD. METHODS: Using an automated surface-based approach (FreeSurfer), cortical thickness was assessed node-by-node over the entire cerebral cortex in adolescents with GAD and no co-occurring major depressive disorder (n=13) and healthy subjects (n=19). RESULTS: Compared with healthy adolescents, youth with GAD exhibited increased cortical thickness in the right inferolateral and ventromedial prefrontal cortex (i.e., inferior frontal gyrus), the left inferior and middle temporal cortex as well as the right lateral occipital cortex. No relationships were observed between cortical thickness and the severity of anxiety symptoms in the significant regions that were identified in the vertex-wise analysis. CONCLUSIONS: These findings suggest that, in adolescents with GAD, abnormalities in cortical thickness are present in an ensemble of regions responsible for fear learning, fear extinction, reflective functioning (e.g., mentalization), and regulation of the amygdala.


Assuntos
Transtornos de Ansiedade/patologia , Córtex Cerebral/patologia , Adolescente , Tonsila do Cerebelo/patologia , Transtornos de Ansiedade/fisiopatologia , Transtornos de Ansiedade/psicologia , Emoções/fisiologia , Medo/fisiologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/patologia
19.
Bipolar Disord ; 16(7): 703-12, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24990479

RESUMO

OBJECTIVES: Despite different treatments and courses of illness, depressive symptoms appear similar in major depressive disorder (MDD) and bipolar I disorder (BP-I). This similarity of depressive symptoms suggests significant overlap in brain pathways underlying neurovegetative, mood, and cognitive symptoms of depression. These shared brain regions might be expected to exhibit similar activation in individuals with MDD and BP-I during functional magnetic resonance imaging (fMRI). METHODS: fMRI was used to compare regional brain activation in participants with BP-I (n = 25) and MDD (n = 25) during a depressive episode as well as 25 healthy comparison (HC) participants. During the scans, participants performed an attentional task that incorporated emotional pictures. RESULTS: During the viewing of emotional images, subjects with BP-I showed decreased activation in the middle occipital gyrus, lingual gyrus, and middle temporal gyrus compared to both subjects with MDD and HC participants. During attentional processing, participants with MDD had increased activation in the parahippocampus, parietal lobe, and postcentral gyrus. However, among these regions, only the postcentral gyrus also showed differences between MDD and HC participants. CONCLUSIONS: No differences in cortico-limbic regions were found between participants with BP-I and MDD during depression. Instead, the major differences occurred in primary and secondary visual processing regions, with decreased activation in these regions in BP-I compared to major depression. These differences were driven by abnormal decreases in activation seen in the participants with BP-I. Posterior activation changes are a common finding in studies across mood states in participants with BP-I.


Assuntos
Transtorno Bipolar/complicações , Encéfalo/fisiopatologia , Depressão/etiologia , Depressão/patologia , Transtorno Depressivo Maior/complicações , Adulto , Atenção/fisiologia , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Cognição/fisiologia , Emoções/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Oxigênio/sangue , Adulto Jovem
20.
Addiction ; 109(11): 1901-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24962329

RESUMO

AIMS: To compare regional brain activation among adolescents with bipolar disorder and co-occurring cannabis use disorder. DESIGN: Cross-sectional study. SETTING: Cincinnati, OH, USA. PARTICIPANTS: Adolescents with bipolar disorder (BP, n = 14), adolescents with cannabis use disorder (MJ, n = 13), adolescents with co-occurring cannabis use and bipolar disorders (BPMJ, n = 25) and healthy adolescents (HC, n = 15). MEASUREMENTS: Cannabis craving, substance use, Blood Oxygenation Level Dependent (BOLD) signal assessed by the Marijuana Craving Questionnaire (MCQ), Teen-Addiction Severity Index (T-ASI) and a cannabis cue-reactivity task during a functional magnetic resonance imaging (fMRI) session, respectively. FINDINGS: The BP group exhibited significantly greater brain activation than the BPMJ group in the right amygdala (F = 4.14, P = 0.046), left nucleus accumbens (F = 3.8, P = 0.02), left thalamus (F = 3.8, P < 0.05) and the right thalamus (F = 6.2, P = 0.02). The BP group exhibited significantly greater activation than the HC group in the left nucleus accumbens (F = 11.5, P = 0.0001), right thalamus (F = 4.9, P = 0.03) and the left striatum (F = 3.6, P = 0.04). Left amygdala activation of the BPMJ group trended towards being significantly negatively correlated with the number of joints smoked (R = -0.4, P = 0.06). CONCLUSIONS: Bipolar adolescents with comorbid cannabis use do not exhibit the same over-activation of the regions involved in emotional processing as seen in adolescents with bipolar disorder alone. The absence of these findings in patients with comorbid bipolar and cannabis use disorders suggests that these individuals may have a unique endophenotype of bipolar disorder or that cannabis use may alter brain activation uniquely in bipolar disorder patients who use cannabis.


Assuntos
Transtorno Bipolar/epidemiologia , Transtorno Bipolar/fisiopatologia , Encéfalo/fisiopatologia , Abuso de Maconha/epidemiologia , Abuso de Maconha/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Comorbidade , Estudos Transversais , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Adulto Jovem
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