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1.
Artigo em Inglês | MEDLINE | ID: covidwho-381838

RESUMO

OBJECTIVE: To describe a novel case of coronavirus disease 2019 (COVID-19)-associated acute necrotizing encephalopathy (ANE) in a patient with aplastic anemia where there was early brain stem-predominant involvement. METHODS: Evaluation of cause, clinical symptoms, and treatment response. RESULTS: A 59-year-old woman with a background of transfusion-dependent aplastic anemia presented with seizures and reduced level of consciousness 10 days after the onset of subjective fever, cough, and headache. Nasopharyngeal swab testing for severe acute respiratory syndrome coronavirus (SARS-CoV-2) was positive, and CT during admission demonstrated diffuse swelling of the brain stem. She required intubation and mechanical ventilation for airway protection, given her reduced level of consciousness. The patient's condition deteriorated, and MRI on day 6 demonstrated worsening brain stem swelling with symmetrical hemorrhagic lesions in the brain stem, amygdalae, putamina, and thalamic nuclei. Appearances were consistent with hemorrhagic ANE with early brain stem involvement. The patient showed no response to steroid therapy and died on the eighth day of admission. CONCLUSIONS: COVID-19 may be associated with an acute severe encephalopathy and, in this case, was considered most likely to represent an immune-mediated phenomenon. As the pandemic continues, we anticipate that the spectrum of neurologic presentation will broaden. It will be important to delineate the full clinical range of emergent COVID-19-related neurologic disease.


Assuntos
Anemia Aplástica/complicações , Infecções por Coronavirus/complicações , Leucoencefalite Hemorrágica Aguda/etiologia , Pneumonia Viral/complicações , Tonsila do Cerebelo/diagnóstico por imagem , Anemia Aplástica/terapia , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Edema Encefálico/fisiopatologia , Edema Encefálico/terapia , Tronco Encefálico/diagnóstico por imagem , Infecções por Coronavirus/terapia , Dexametasona/uso terapêutico , Imagem de Difusão por Ressonância Magnética , Evolução Fatal , Feminino , Glucocorticoides/uso terapêutico , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/fisiopatologia , Leucoencefalite Hemorrágica Aguda/diagnóstico por imagem , Leucoencefalite Hemorrágica Aguda/fisiopatologia , Leucoencefalite Hemorrágica Aguda/terapia , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Pandemias , Transfusão de Plaquetas , Pneumonia Viral/terapia , Hemorragia Putaminal/diagnóstico por imagem , Hemorragia Putaminal/etiologia , Hemorragia Putaminal/fisiopatologia , Respiração Artificial , Convulsões/etiologia , Núcleos Talâmicos/diagnóstico por imagem , Tomografia Computadorizada por Raios X
2.
Proc Natl Acad Sci U S A ; 117(21): 11781-11787, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32385158

RESUMO

Benzodiazepines (BZDs) represent the gold standard of anxiolytic pharmacotherapy; however, their clinical benefit is limited by side effects and addictive potential. Consequently, there is an urgent need to develop novel and safe anxiolytics. The peptide hormone oxytocin (OXT) exhibits anxiolytic-like properties in animals and humans, but whether OXT and BZDs share similar effects on the neural circuitry of fear is unclear. Therefore, the rationale of this ultra-high-field functional MRI (fMRI) study was to test OXT against the clinical comparator lorazepam (LZP) with regard to their neuromodulatory effects on local and network responses to fear-related stimuli. One hundred twenty-eight healthy male participants volunteered in this randomized double-blind, placebo-controlled, between-group study. Before scanning using an emotional face-matching paradigm, participants were randomly administered a single dose of OXT (24 IU), LZP (1 mg), or placebo. On the behavioral level, LZP, but not OXT, caused mild sedation, as evidenced by a 19% increase in reaction times. On the neural level, both OXT and LZP inhibited responses to fearful faces vs. neutral faces within the centromedial amygdala (cmA). In contrast, they had different effects on intra-amygdalar connectivity; OXT strengthened the coupling between the cmA and basolateral amygdala, whereas LZP increased the interplay between the cmA and superficial amygdala. Furthermore, OXT, but not LZP, enhanced the coupling between the cmA and the precuneus and dorsomedial prefrontal cortex. These data implicate inhibition of the cmA as a common denominator of anxiolytic action, with only OXT inducing large-scale connectivity changes of potential therapeutic relevance.


Assuntos
Tonsila do Cerebelo , Medo/efeitos dos fármacos , Lorazepam/farmacologia , Ocitocina/farmacologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/fisiologia , Medo/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Neurotransmissores/farmacologia , Adulto Jovem
3.
Artigo em Inglês | MEDLINE | ID: mdl-32457227

RESUMO

OBJECTIVE: To describe a novel case of coronavirus disease 2019 (COVID-19)-associated acute necrotizing encephalopathy (ANE) in a patient with aplastic anemia where there was early brain stem-predominant involvement. METHODS: Evaluation of cause, clinical symptoms, and treatment response. RESULTS: A 59-year-old woman with a background of transfusion-dependent aplastic anemia presented with seizures and reduced level of consciousness 10 days after the onset of subjective fever, cough, and headache. Nasopharyngeal swab testing for severe acute respiratory syndrome coronavirus (SARS-CoV-2) was positive, and CT during admission demonstrated diffuse swelling of the brain stem. She required intubation and mechanical ventilation for airway protection, given her reduced level of consciousness. The patient's condition deteriorated, and MRI on day 6 demonstrated worsening brain stem swelling with symmetrical hemorrhagic lesions in the brain stem, amygdalae, putamina, and thalamic nuclei. Appearances were consistent with hemorrhagic ANE with early brain stem involvement. The patient showed no response to steroid therapy and died on the eighth day of admission. CONCLUSIONS: COVID-19 may be associated with an acute severe encephalopathy and, in this case, was considered most likely to represent an immune-mediated phenomenon. As the pandemic continues, we anticipate that the spectrum of neurologic presentation will broaden. It will be important to delineate the full clinical range of emergent COVID-19-related neurologic disease.


Assuntos
Anemia Aplástica/complicações , Infecções por Coronavirus/complicações , Leucoencefalite Hemorrágica Aguda/etiologia , Pneumonia Viral/complicações , Tonsila do Cerebelo/diagnóstico por imagem , Anemia Aplástica/terapia , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Edema Encefálico/fisiopatologia , Edema Encefálico/terapia , Tronco Encefálico/diagnóstico por imagem , Infecções por Coronavirus/terapia , Dexametasona/uso terapêutico , Imagem de Difusão por Ressonância Magnética , Evolução Fatal , Feminino , Glucocorticoides/uso terapêutico , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/fisiopatologia , Leucoencefalite Hemorrágica Aguda/diagnóstico por imagem , Leucoencefalite Hemorrágica Aguda/fisiopatologia , Leucoencefalite Hemorrágica Aguda/terapia , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Pandemias , Transfusão de Plaquetas , Pneumonia Viral/terapia , Hemorragia Putaminal/diagnóstico por imagem , Hemorragia Putaminal/etiologia , Hemorragia Putaminal/fisiopatologia , Respiração Artificial , Convulsões/etiologia , Núcleos Talâmicos/diagnóstico por imagem , Tomografia Computadorizada por Raios X
4.
Am J Psychiatry ; 177(6): 518-525, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32375538

RESUMO

OBJECTIVE: Sleep patterns in children with autism spectrum disorder (ASD) appear to diverge from typical development in the second or third year of life. Little is known, however, about the occurrence of sleep problems in infants who later develop ASD and possible effects on early brain development. In a longitudinal neuroimaging study of infants at familial high or low risk for ASD, parent-reported sleep onset problems were examined in relation to subcortical brain volumes in the first 2 years of life. METHODS: A total of 432 infants were included across three study groups: infants at high risk who developed ASD (N=71), infants at high risk who did not develop ASD (N=234), and infants at low risk (N=127). Sleep onset problem scores (derived from an infant temperament measure) were evaluated in relation to longitudinal high-resolution T1 and T2 structural imaging data acquired at 6, 12, and 24 months of age. RESULTS: Sleep onset problems were more common at 6-12 months among infants who later developed ASD. Infant sleep onset problems were related to hippocampal volume trajectories from 6 to 24 months only for infants at high risk who developed ASD. Brain-sleep relationships were specific to the hippocampus; no significant relationships were found with volume trajectories of other subcortical structures examined (the amygdala, caudate, globus pallidus, putamen, and thalamus). CONCLUSIONS: These findings provide initial evidence that sleep onset problems in the first year of life precede ASD diagnosis and are associated with altered neurodevelopmental trajectories in infants at high familial risk who go on to develop ASD. If replicated, these findings could provide new insights into a potential role of sleep difficulties in the development of ASD.


Assuntos
Transtorno do Espectro Autista/epidemiologia , Hipotálamo/diagnóstico por imagem , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/patologia , Pré-Escolar , Feminino , Globo Pálido/diagnóstico por imagem , Globo Pálido/patologia , Humanos , Hipotálamo/patologia , Lactente , Imagem por Ressonância Magnética , Masculino , Tamanho do Órgão , Putamen/diagnóstico por imagem , Putamen/patologia , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Latência do Sono , Tálamo/diagnóstico por imagem , Tálamo/patologia
5.
J Neurosci ; 40(18): 3646-3656, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32238480

RESUMO

As an important cognitive bias, the framing effect shows that our decision preferences are sensitive to the verbal description (i.e., frame) of options. This study focuses on the neural underpinnings of the social framing effect, which is based on decision-making regarding other people. A novel paradigm was used in which participants made a trade-off between economic benefits and the feelings of others. This decision was described as either a "harm" to, or "not helping," other persons in two conditions (Harm frame vs Help frame). Both human males and females were recruited. Participants behaved more prosocially for Harm frame compared with Help frame, resulting in a significant social framing effect. Using functional magnetic resonance imaging, Experiment 1 showed that the social framing effect was associated with stronger activation in the temporoparietal junction (TPJ), especially its right part. The functional connectivity between the right TPJ (rTPJ) and medial prefrontal cortex predicted the social framing effect on the group level. In Experiment 2, we used transcranial direct current stimulation to modulate the activity of the rTPJ and found that the social framing effect became more prominent under anodal (excitatory) stimulation, while the nonsocial framing effect elicited by the economic gain/loss gambling frame remained unaffected. The rTPJ results might be associated with moral conflicts modulated by the social consequences of an action or different levels of mentalizing with others under different frame conditions, but alternative interpretations are also worth noting. These findings could help elucidate the psychological mechanisms of the social framing effect.SIGNIFICANCE STATEMENT Previous studies have suggested that the framing effect is generated from an interaction between the amygdala and anterior cingulate cortex. This opinion, however, is based on findings from nonsocial framing tasks. Recent research has highlighted the importance of distinguishing between the social and nonsocial framing effects. The current study focuses on the social framing effect and finds out that the temporoparietal junction and its functional connectivity with the medial prefrontal cortex play a significant role. Additionally, modulating the activity of this region leads to changes in social (but not nonsocial) framing effect. Broadly speaking, these findings help understand the difference in neural mechanisms between social and nonsocial decision-making. Meanwhile, they might be illuminating to promote helping behavior in society.


Assuntos
Tonsila do Cerebelo/fisiologia , Tomada de Decisões/fisiologia , Imagem por Ressonância Magnética/métodos , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Tonsila do Cerebelo/diagnóstico por imagem , Feminino , Humanos , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
6.
J Clin Neurosci ; 75: 199-203, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32334739

RESUMO

In the present paper, we aimed to investigate hippocampus and amygdala volumes in a group of patients with antisocial personality disorder and hypothesized that hippocampus and amygdala volume alterations would be observed. It was measured hippocampus and amygdala volumes of twenty patients with antisocial personality disorder and those of healthy control subjects. We found that both sides of hippocampus and amygdala volumes of patients with antisocial personality disorder were statistically significantly reduced compared to those healthy control subjects, and observed statistically important correlations between the left and right and left hippocampus and left amygdala volumes, and age, some results on scale scores. Consequently, the present study suggest that hippocampus and amygdala volumes of patients with antisocial personality disorder had abnormally smaller than those of healthy control subjects, considering that these abnormalities might be associated with at least some clinical features of antisocial personality disorder. However, longitudinal studies are needed to assess causality of this relationship.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Transtorno da Personalidade Antissocial/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Adolescente , Adulto , Transtorno da Personalidade Antissocial/psicologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Adulto Jovem
7.
Psychopharmacology (Berl) ; 237(6): 1813-1826, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32162103

RESUMO

RATIONALE: Excessive fear and anxiety, coupled with corticolimbic dysfunction, are core features of stress- and trauma-related psychopathology, such as posttraumatic stress disorder (PTSD). Interestingly, low doses of ∆9-tetrahydrocannabinol (THC) can produce anxiolytic effects, reduce threat-related amygdala activation, and enhance functional coupling between the amygdala and medial prefrontal cortex and adjacent rostral cingulate cortex (mPFC/rACC) during threat processing in healthy adults. Together, these findings suggest the cannabinoid system as a potential pharmacological target in the treatment of excess fear and anxiety. However, the effects of THC on corticolimbic functioning in response to threat have not be investigated in adults with trauma-related psychopathology. OBJECTIVE: To address this gap, the present study tests the effects of an acute low dose of THC on corticolimbic responses to threat in three groups of adults: (1) non-trauma-exposed healthy controls (HC; n = 25), (2) trauma-exposed adults without PTSD (TEC; n = 27), and (3) trauma-exposed adults with PTSD (n = 19). METHODS: Using a randomized, double-blind, placebo-controlled, between-subjects design, 71 participants were randomly assigned to receive either THC or placebo (PBO) and subsequently completed a well-established threat processing paradigm during functional magnetic resonance imaging. RESULTS: In adults with PTSD, THC lowered threat-related amygdala reactivity, increased mPFC activation during threat, and increased mPFC-amygdala functional coupling. CONCLUSIONS: These preliminary data suggest that THC modulates threat-related processing in trauma-exposed individuals with PTSD, which may prove advantageous as a pharmacological approach to treating stress- and trauma-related psychopathology.


Assuntos
Tonsila do Cerebelo/efeitos dos fármacos , Dronabinol/farmacologia , Medo/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Canabinoides/farmacologia , Canabinoides/uso terapêutico , Método Duplo-Cego , Dronabinol/uso terapêutico , Medo/psicologia , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia
8.
Proc Natl Acad Sci U S A ; 117(7): 3808-3818, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32015137

RESUMO

The amygdala is central to the pathophysiology of many psychiatric illnesses. An imprecise understanding of how the amygdala fits into the larger network organization of the human brain, however, limits our ability to create models of dysfunction in individual patients to guide personalized treatment. Therefore, we investigated the position of the amygdala and its functional subdivisions within the network organization of the brain in 10 highly sampled individuals (5 h of fMRI data per person). We characterized three functional subdivisions within the amygdala of each individual. We discovered that one subdivision is preferentially correlated with the default mode network; a second is preferentially correlated with the dorsal attention and fronto-parietal networks; and third subdivision does not have any networks to which it is preferentially correlated relative to the other two subdivisions. All three subdivisions are positively correlated with ventral attention and somatomotor networks and negatively correlated with salience and cingulo-opercular networks. These observations were replicated in an independent group dataset of 120 individuals. We also found substantial across-subject variation in the distribution and magnitude of amygdala functional connectivity with the cerebral cortex that related to individual differences in the stereotactic locations both of amygdala subdivisions and of cortical functional brain networks. Finally, using lag analyses, we found consistent temporal ordering of fMRI signals in the cortex relative to amygdala subdivisions. Altogether, this work provides a detailed framework of amygdala-cortical interactions that can be used as a foundation for models relating aberrations in amygdala connectivity to psychiatric symptoms in individual patients.


Assuntos
Tonsila do Cerebelo/fisiologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Atenção , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Feminino , Humanos , Individualidade , Imagem por Ressonância Magnética , Masculino , Psiquiatria , Adulto Jovem
9.
PLoS One ; 15(1): e0226486, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31931515

RESUMO

Treatment-resistant depression (TRD) occurs in many patients and causes high morbidity and mortality. Because TRD subjects are particularly difficult to study especially longitudinally, biological data remain very limited. In a preliminary study to judge feasibility and power, 25 TRD patients were referred from specialty psychiatric practices. All were severely and chronically depressed and mostly had comorbid psychiatric disorders as is typical in TRD. Nine patients were able to complete all required components of the protocol that included diagnostic interview; rating scales; clinical magnetic resonance imaging; medication washout; treatment with maximally tolerated olanzapine-fluoxetine combination for 8 weeks; and pre- and post-treatment fluorodeoxyglucose positron emission tomography. This drug combination is an accepted standard of treatment for TRD. Dropouts arose from worsening depression, insomnia, and anxiety. One patient remitted; three responded. A priori regions of interest included the amygdala and subgenual cingulate cortex (sgACC; Brodmann area BA25). Responders showed decreased metabolism with treatment in the right amygdala that correlated with clinical response; no significant changes in BA25; better response to treatment the higher the baseline BA25 metabolism; and decreased right ventromedial prefrontal metabolism (VMPFC; broader than BA25) with treatment which did not correlate with depression scores. The baseline metabolism of all individuals showed heterogeneous patterns when compared to a normative metabolic database. Although preliminary given the sample size, this study highlights several issues important for future work: marked dropout rate in this study design; need for large sample size for adequate power; baseline metabolic heterogeneity of TRD requiring careful subject characterization for future studies of interventions; relationship of amygdala activity decreases with response; and the relationship between baseline sgACC and VMPFC activity with response. Successful treatment of TRD with olanzapine-fluoxetine combination shows changes in cerebral metabolism like those seen in treatment-responsive major depression.


Assuntos
Benzodiazepinas/uso terapêutico , Encéfalo/metabolismo , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Fluoxetina/uso terapêutico , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/metabolismo , Encéfalo/diagnóstico por imagem , Transtorno Depressivo Resistente a Tratamento/metabolismo , Transtorno Depressivo Resistente a Tratamento/patologia , Combinação de Medicamentos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/metabolismo , Índice de Gravidade de Doença
11.
Zool Res ; 41(2): 199-202, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31945811

RESUMO

Changes in fine structures of the brain over a life span can have robust effects on neural activity and brain function, which both play crucial roles in neurodegenerative diseases. Clinically, however, low-resolution MRI only provides limited information about fine brain structures. Here, using high-resolution 9.4 T MRI, we established a set of structural images and explored the fine structures of the claustrum, hippocampus, amygdala complex, and subregions of the amygdala complex (BLA, including lateral, basal, and accessory basal subnuclei) in rhesus macaque (Macaca mulatta) brains. Based on these high-resolution images, we were able to discriminate the subregional boundaries accurately and, at the same time, obtain the volume of each brain nuclei. Thus, advanced high-resolution 9.4 T MRI not only provides a new strategy for early diagnosis of neurodegenerative diseases, but also provides the ability to observe fine structural changes in the brain across a life span.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Macaca mulatta/anatomia & histologia , Animais , Feminino , Imagem por Ressonância Magnética , Valores de Referência
12.
Brain Connect ; 10(1): 3-17, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31950847

RESUMO

Evolutionary-developmental theories consider the evolved mechanisms underlying adaptive behavioral strategies shaped in response to early environmental cues. Identifying neural mechanisms mediating processes of conditional adaptation in humans is an active area of research. Resting-state functional magnetic resonance imaging (RS-fMRI) captures functional connectivity theorized to represent the underlying functional architecture of the brain. This allows for investigating how underlying functional brain connections are related to early experiences during development, as well as current traits and behaviors. This review explores the potential of RS-fMRI of the amygdala (AMY) for advancing research on the neural mechanisms underlying adaptive strategies developed in early adverse environments. RS-fMRI studies of early life stress (ELS) and AMY functional connectivity within the frame of evolutionary theories are reviewed, specifically regarding the development of self-regulatory strategies. The potential of RS-fMRI for investigating the effects of ELS on developmental trajectories of self-regulation is discussed.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Humanos , Acontecimentos que Mudam a Vida , Imagem por Ressonância Magnética/métodos , Rede Nervosa/fisiologia , Vias Neurais/fisiologia , Córtex Pré-Frontal/fisiologia , Descanso/fisiologia , Estresse Psicológico/diagnóstico por imagem
13.
Nat Hum Behav ; 4(2): 201-214, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31712764

RESUMO

Individuals differ in how they learn from experience. In Pavlovian conditioning models, where cues predict reinforcer delivery at a different goal location, some animals-called sign-trackers-come to approach the cue, whereas others, called goal-trackers, approach the goal. In sign-trackers, model-free phasic dopaminergic reward-prediction errors underlie learning, which renders stimuli 'wanted'. Goal-trackers do not rely on dopamine for learning and are thought to use model-based learning. We demonstrate this double dissociation in 129 male humans using eye-tracking, pupillometry and functional magnetic resonance imaging informed by computational models of sign- and goal-tracking. We show that sign-trackers exhibit a neural reward prediction error signal that is not detectable in goal-trackers. Model-free value only guides gaze and pupil dilation in sign-trackers. Goal-trackers instead exhibit a stronger model-based neural state prediction error signal. This model-based construct determines gaze and pupil dilation more in goal-trackers.


Assuntos
Gânglios da Base/fisiologia , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Condicionamento Clássico/fisiologia , Objetivos , Modelos Biológicos , Recompensa , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiologia , Antecipação Psicológica/fisiologia , Gânglios da Base/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Medições dos Movimentos Oculares , Fixação Ocular/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Núcleo Accumbens/diagnóstico por imagem , Núcleo Accumbens/fisiologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Pupila/fisiologia , Putamen/diagnóstico por imagem , Putamen/fisiologia , Adulto Jovem
14.
Radiol Med ; 125(1): 80-86, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31529401

RESUMO

OBJECTIVE: To observe the structural changes of gray matter nuclei in patients with acute carbon monoxide intoxication by diffusion tensor imaging (DTI), quantify the degree of deep gray matter damage in the brain by adopting imaging technology and research the characteristics of the damage and its pertinence with memory and cognitive impairment. METHODS: Twenty-five patients with acute carbon monoxide intoxication and 25 healthy volunteers matched in sex and age were examined by routine head MRI and diffusion tensor imaging (DTI). Bilateral hippocampus, dater nucleus, thalamus, amygdala, globus pallidus and putamen were taken as regions of interest. The mean diffusion coefficient (MD), anisotropic fraction (FA) and appearance of deep gray matter nucleus in patients with acute carbon monoxide intoxication were analyzed. It found that the change of diffusion coefficient (ADC) and its clinical correlation with cognitive impairment were generated by carbon monoxide intoxication. RESULTS: Compared with the healthy control group, the FA values of bilateral globus pallidus, hippocampus, dater nucleus and putamen decreased, while the FA values of amygdala and thalamus had no statistical significance; the MD values and ADC values of hippocampus, globus pallidus and putamen increased, while the MD and ADC values of dater nucleus, thalamus and amygdala had no statistical significance, either. CONCLUSION: DTI is capable of sensitively reflecting the damage of gray matter nuclei caused by acute carbon monoxide intoxication and quantifying the degree of hypoxic brain damage in a certain extent, and may be related to cognitive impairment.


Assuntos
Lesões Encefálicas Difusas/diagnóstico por imagem , Intoxicação por Monóxido de Carbono/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Substância Cinzenta/diagnóstico por imagem , Doença Aguda , Adulto , Idoso , Tonsila do Cerebelo/diagnóstico por imagem , Anisotropia , Estudos de Casos e Controles , Cognição , Feminino , Globo Pálido/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Giro Para-Hipocampal/diagnóstico por imagem , Putamen/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Vigília , Adulto Jovem
15.
Nat Hum Behav ; 4(1): 100-110, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685950

RESUMO

Are you feeling anxious? Did you sleep poorly last night? Sleep disruption is a recognized feature of all anxiety disorders. Here, we investigate the basic brain mechanisms underlying the anxiogenic impact of sleep loss. Additionally, we explore whether subtle, societally common reductions in sleep trigger elevated next-day anxiety. Finally, we examine what it is about sleep, physiologically, that provides such an overnight anxiety-reduction benefit. We demonstrate that the anxiogenic impact of sleep loss is linked to impaired medial prefrontal cortex activity and associated connectivity with extended limbic regions. In contrast, non-rapid eye movement (NREM) slow-wave oscillations offer an ameliorating, anxiolytic benefit on these brain networks following sleep. Of societal relevance, we establish that even modest night-to-night reductions in sleep across the population predict consequential day-to-day increases in anxiety. These findings help contribute to an emerging framework explaining the intimate link between sleep and anxiety and further highlight the prospect of non-rapid eye movement sleep as a therapeutic target for meaningfully reducing anxiety.


Assuntos
Ansiedade/etiologia , Ansiedade/fisiopatologia , Neuroimagem Funcional , Sistema Límbico/fisiopatologia , Rede Nervosa/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Privação do Sono/complicações , Privação do Sono/fisiopatologia , Fases do Sono/fisiologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Ansiedade/diagnóstico por imagem , Ansiedade/prevenção & controle , Transtornos de Ansiedade/prevenção & controle , Eletroencefalografia , Feminino , Humanos , Sistema Límbico/diagnóstico por imagem , Imagem por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Privação do Sono/diagnóstico por imagem , Adulto Jovem
16.
Neuroimaging Clin N Am ; 30(1): 115-123, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759567

RESUMO

This review summarizes current knowledge obtained from psychoradiological studies of posttraumatic stress disorder (PTSD). We first focus on 3 key anatomic structures (hippocampus, amygdala, and medial prefrontal cortex) and the functional circuits to which they contribute. In addition, we discuss the triple-network model, a widely accepted neurobiological model of PTSD that explains the vast majority of neuroimaging findings, as well as their interactions and relationships to functional disruptions in PTSD.


Assuntos
Tonsila do Cerebelo/patologia , Hipocampo/patologia , Neuroimagem/métodos , Córtex Pré-Frontal/patologia , Transtornos de Estresse Pós-Traumáticos/patologia , Tonsila do Cerebelo/diagnóstico por imagem , Regulação Emocional , Função Executiva , Hipocampo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Fatores de Risco , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem
17.
Neural Plast ; 2019: 8549237, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885536

RESUMO

Affective disorders, such as anxiety and depression, are common comorbidities associated with chronic insomnia disorder (CID). However, the underlying neural mechanisms of these comorbidities are still not clear. The present study is aimed at investigating structural changes in the amygdala of CID patients using surface-based shape analysis. A total of 65 medication-naive patients with CID and 55 healthy controls (HCs) matched for age, sex, and years of education were enrolled in this study and were subjected to structural magnetic resonance imaging (MRI). The Oxford Centre for Functional MRI of the Brain (FMRIB) created an Integrated Registration and Segmentation Tool (FIRST) that was employed in this study to assess the volumetric and surface alterations in patients with CID. Shape correlations between the amygdala and clinical features were also analyzed. Atrophic changes in the amygdala were observed at the local level, not for the entire amygdala volume. The left atrophic changes in the amygdala were in the superficial and basolateral nuclei while right atrophic changes were in the basolateral nuclei in CID patients. Insomnia severity was associated with the centromedial right amygdala while anxiety was linked with the basolateral nuclei. These findings indicate localized amygdala atrophy in CID. Separate amygdala regions are associated with insomnia and anxiety in CID. This evidence helps elucidate the neural mechanisms underlying the bidirectional relationship between insomnia and anxiety.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Ansiedade/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/métodos , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Adulto , Ansiedade/epidemiologia , Ansiedade/psicologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/psicologia
18.
Stereotact Funct Neurosurg ; 97(4): 255-265, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618749

RESUMO

Selective laser amygdalohippocampotomy (SLAH) is a minimally invasive surgical treatment for medial temporal lobe epilepsy. Visual field deficits (VFDs) are a significant potential complication. The objective of this study was to determine the relationship between VFDs and potential mechanisms of injury to the optic radiations and lateral geniculate nucleus. We performed a retrospective cross-sectional analysis of 3 patients (5.2%) who developed persistent VFDs after SLAH within our larger series (n = 58), 15 healthy individuals and 10 SLAH patients without visual complications. Diffusion tractography was used to evaluate laser catheter penetration of the optic radiations. Using a complementary approach, we evaluated evidence for focal microstructural tissue damage within the optic radiations and lateral geniculate nucleus. Overablation and potential heat radiation were assessed by quantifying ablation and choroidal fissure CSF volumes as well as energy deposited during SLAH.SLAH treatment parameters did not distinguish VFD patients. Atypically high overlap between the laser catheter and optic radiations was found in 1/3 VFD patients and was accompanied by focal reductions in fractional anisotropy where the catheter entered the lateral occipital white matter. Surprisingly, lateral geniculate tissue diffusivity was abnormal following, but also preceding, SLAH in patients who subsequently developed a VFD (all p = 0.005).In our series, vision-related complications following SLAH, which appear to occur less frequently than following open temporal lobe -surgery, were not directly explained by SLAH treatment parameters. Instead, our data suggest that variations in lateral geniculate structure may influence susceptibility to indirect heat injury from transoccipital SLAH.


Assuntos
Tonsila do Cerebelo/cirurgia , Hipocampo/cirurgia , Terapia a Laser/efeitos adversos , Complicações Pós-Operatórias/etiologia , Técnicas Estereotáxicas/efeitos adversos , Transtornos da Visão/etiologia , Adolescente , Adulto , Idoso , Tonsila do Cerebelo/diagnóstico por imagem , Estudos Transversais , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Feminino , Seguimentos , Hipocampo/diagnóstico por imagem , Humanos , Terapia a Laser/tendências , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Psicocirurgia/efeitos adversos , Psicocirurgia/tendências , Estudos Retrospectivos , Fatores de Risco , Técnicas Estereotáxicas/tendências , Transtornos da Visão/diagnóstico por imagem , Campos Visuais/fisiologia , Adulto Jovem
19.
Nat Commun ; 10(1): 4835, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645545

RESUMO

Learning the structure of the world can be driven by reinforcement but also occurs incidentally through experience. Reinforcement learning theory has provided insight into how prediction errors drive updates in beliefs but less attention has been paid to the knowledge resulting from such learning. Here we contrast associative structures formed through reinforcement and experience of task statistics. BOLD neuroimaging in human volunteers demonstrates rigid representations of rewarded sequences in temporal pole and posterior orbito-frontal cortex, which are constructed backwards from reward. By contrast, medial prefrontal cortex and a hippocampal-amygdala border region carry reward-related knowledge but also flexible statistical knowledge of the currently relevant task model. Intriguingly, ventral striatum encodes prediction error responses but not the full RL- or statistically derived task knowledge. In summary, representations of task knowledge are derived via multiple learning processes operating at different time scales that are associated with partially overlapping and partially specialized anatomical regions.


Assuntos
Aprendizagem por Associação/fisiologia , Encéfalo/diagnóstico por imagem , Reforço Psicológico , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiologia , Encéfalo/fisiologia , Feminino , Neuroimagem Funcional , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Humanos , Aprendizagem/fisiologia , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/fisiologia , Adulto Jovem
20.
Gac Med Mex ; 155(Suppl 1): S49-S55, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31638610

RESUMO

Background: Neurosurgical treatment, although controversial, is considered a useful resource in the treatment of chronic psychiatric diseases such as refractory aggressiveness. Objective: To evaluate the clinical results and side effects of posteromedial hypothalamotomy associated with amygdalotomy in patients with refractory aggressiveness. Method: A clinical trial was conducted in patients with chronic aggressiveness and refractory to pharmacological treatment. A central amygdalotomy associated with posteromedial hypothalamotomy was performed using thermo-coagulation by radiofrequency. The degree of aggressiveness was quantified by the Yudofsky's global scale of aggression. Postoperative changes in aggressive behavior continued to be evaluated every 6 months for at least 36 months. Results: A statistically significant change in aggressive behavior was observed during 36 months of follow-up. The collateral effects of the association of both procedures are described, the most frequent being drowsiness and some cases of reduction in sexual behavior. Conclusion: Symmetric and simultaneous unilateral lesions of the central nucleus of the amygdala and the posteromedial hypothalamus contralateral to motor dominance give the same clinical effect in the reduction of the pathological aggression that the bilateral lesions.


Assuntos
Agressão , Tonsila do Cerebelo/cirurgia , Hipotálamo/cirurgia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Eletrocoagulação/efeitos adversos , Eletrocoagulação/métodos , Feminino , Humanos , Hipotálamo/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Psicocirurgia/métodos , Ablação por Radiofrequência/efeitos adversos , Ablação por Radiofrequência/métodos , Resultado do Tratamento , Adulto Jovem
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