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1.
Bull World Health Organ ; 98(4): 270-276, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32284651

RESUMO

The application of digital technology to psychiatry research is rapidly leading to new discoveries and capabilities in the field of mobile health. However, the increase in opportunities to passively collect vast amounts of detailed information on study participants coupled with advances in statistical techniques that enable machine learning models to process such information has raised novel ethical dilemmas regarding researchers' duties to: (i) monitor adverse events and intervene accordingly; (ii) obtain fully informed, voluntary consent; (iii) protect the privacy of participants; and (iv) increase the transparency of powerful, machine learning models to ensure they can be applied ethically and fairly in psychiatric care. This review highlights emerging ethical challenges and unresolved ethical questions in mobile health research and provides recommendations on how mobile health researchers can address these issues in practice. Ultimately, the hope is that this review will facilitate continued discussion on how to achieve best practice in mobile health research within psychiatry.


L'application des technologies numériques à la recherche psychiatrique entraîne rapidement de nouvelles découvertes et capacités en matière de santé mobile. Cependant, la multiplication des opportunités de recueillir passivement d'immenses quantités d'informations détaillées sur les participants aux études combinée aux progrès des techniques statistiques permettant aux modèles d'apprentissage automatique de traiter de telles informations a soulevé de nouveaux dilemmes éthiques concernant l'obligation des chercheurs: (i) de surveiller les effets indésirables et d'intervenir en conséquence; (ii) d'obtenir un consentement pleinement éclairé et volontaire; (iii) de protéger la vie privée des participants; et enfin, (iv) d'améliorer la transparence des puissants modèles d'apprentissage automatique afin de garantir une application éthique et impartiale dans le domaine des soins psychiatriques. Ce rapport identifie les défis qui en découlent ainsi que les questions éthiques non résolues en matière de santé mobile. Il formule également des recommandations sur la façon dont les chercheurs en santé mobile peuvent résoudre ces problèmes dans la pratique. À terme, nous espérons que ce rapport favorisera la poursuite des discussions portant sur les moyens de définir des méthodes de recherche adéquates pour la santé mobile en psychiatrie.


La aplicación de la tecnología digital a la investigación en psiquiatría está conduciendo rápidamente a descubrimientos y capacidades nuevas en el ámbito de la salud móvil. No obstante, el incremento de las oportunidades para recopilar pasivamente grandes volúmenes de información detallada sobre los participantes en los estudios, junto con los avances en las técnicas de estadística que permiten a los modelos de aprendizaje automático procesar tal información, ha planteado nuevos dilemas éticos relativos a los deberes de los investigadores: (i) hacer un seguimiento de los eventos adversos e intervenir en consecuencia; (ii) obtener un consentimiento voluntario plenamente informado; (iii) proteger la privacidad de los participantes; y (iv) aumentar la transparencia de los modelos potentes de aprendizaje automático para asegurar que puedan aplicarse de manera ética y justa en la atención psiquiátrica. En este análisis se destacan tanto los desafíos éticos nuevos como las cuestiones éticas aún sin resolver en la investigación sobre la salud móvil y se formulan recomendaciones sobre cómo los investigadores de la salud móvil pueden abordar dichas cuestiones en la práctica. En última instancia, se espera que este análisis facilite un debate continuo sobre cómo lograr las mejores prácticas en la investigación de la salud móvil dentro de la psiquiatría.


Assuntos
Ética em Pesquisa , Aprendizado de Máquina/ética , Psiquiatria , Telemedicina/ética , Consentimento Livre e Esclarecido , Privacidade
2.
Psychol Med ; 50(2): 273-283, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30744715

RESUMO

BACKGROUND: Subclinical delusional ideas, including persecutory beliefs, in otherwise healthy individuals are heritable symptoms associated with increased risk for psychotic illness, possibly representing an expression of one end of a continuum of psychosis severity. The identification of variation in brain function associated with these symptoms may provide insights about the neurobiology of delusions in clinical psychosis. METHODS: A resting-state functional magnetic resonance imaging scan was collected from 131 young adults with a wide range of severity of subclinical delusional beliefs, including persecutory ideas. Because of evidence for a key role of the amygdala in fear and paranoia, resting-state functional connectivity of the amygdala was measured. RESULTS: Connectivity between the amygdala and early visual cortical areas, including striate cortex (V1), was found to be significantly greater in participants with high (n = 43) v. low (n = 44) numbers of delusional beliefs, particularly in those who showed persistence of those beliefs. Similarly, across the full sample, the number of and distress associated with delusional beliefs were positively correlated with the strength of amygdala-visual cortex connectivity. Moreover, further analyses revealed that these effects were driven by those who endorsed persecutory beliefs. CONCLUSIONS: These findings are consistent with the hypothesis that aberrant assignments of threat to sensory stimuli may lead to the downstream development of delusional ideas. Taken together with prior findings of disrupted sensory-limbic coupling in psychosis, these results suggest that altered amygdala-visual cortex connectivity could represent a marker of psychosis-related pathophysiology across a continuum of symptom severity.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Delusões/psicologia , Medo/fisiologia , Córtex Visual/fisiopatologia , Adolescente , Delusões/diagnóstico , Medo/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Análise de Regressão , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Adulto Jovem
3.
J Neurosci ; 34(12): 4123-34, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24647934

RESUMO

A parietal-frontal network in primates is thought to support many behaviors occurring in the space around the body, including interpersonal interactions and maintenance of a particular "comfort zone" or distance from other people ("personal space"). To better understand this network in humans, we used functional MRI to measure the responses to moving objects (faces, cars, simple spheres) and the functional connectivity of two regions in this network, the dorsal intraparietal sulcus (DIPS) and the ventral premotor cortex (PMv). We found that both areas responded more strongly to faces that were moving toward (vs away from) subjects, but did not show this bias in response to comparable motion in control stimuli (cars or spheres). Moreover, these two regions were functionally interconnected. Tests of activity-behavior associations revealed that the strength of DIPS-PMv connectivity was correlated with the preferred distance that subjects chose to stand from an unfamiliar person (personal space size). In addition, the magnitude of DIPS and PMv responses was correlated with the preferred level of social activity. Together, these findings suggest that this parietal-frontal network plays a role in everyday interactions with others.


Assuntos
Encéfalo/fisiologia , Relações Interpessoais , Rede Nervosa/fisiologia , Espaço Pessoal , Comportamento Social , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Percepção de Movimento/fisiologia , Vias Neurais/fisiologia
4.
Sci Rep ; 12(1): 1932, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35121741

RESUMO

College students commonly experience psychological distress when faced with intensified academic demands and changes in the social environment. Examining the nature and dynamics of students' affective and behavioral experiences can help us better characterize the correlates of psychological distress. Here, we leveraged wearables and smartphones to study 49 first-year college students continuously throughout the academic year. Affect and sleep, academic, and social behavior showed substantial changes from school semesters to school breaks and from weekdays to weekends. Three student clusters were identified with behavioral and affective dissociations and varying levels of distress throughout the year. While academics were a common stressor for all, the cluster with highest distress stood out by frequent report of social stress. Moreover, the frequency of reporting social, but not academic, stress predicted subsequent clinical symptoms. Two years later, during the COVID-19 pandemic, the first-year cluster with highest distress again stood out by frequent social stress and elevated clinical symptoms. Focus on sustained interpersonal stress, relative to academic stress, might be especially helpful to identify students at heightened risk for psychopathology.


Assuntos
COVID-19/psicologia , Sono , Comportamento Social , Estresse Psicológico , Estudantes/psicologia , Desempenho Acadêmico , Actigrafia , Adolescente , Afeto , Análise por Conglomerados , Feminino , Humanos , Masculino , Adulto Jovem
5.
Sci Rep ; 11(1): 15408, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326370

RESUMO

The ubiquity of smartphones, with their increasingly sophisticated array of sensors, presents an unprecedented opportunity for researchers to collect longitudinal, diverse, temporally-dense data about human behavior while minimizing participant burden. Researchers increasingly make use of smartphones for "digital phenotyping," the collection and analysis of raw phone sensor and log data to study the lived experiences of subjects in their natural environments using their own devices. While digital phenotyping has shown promise in fields such as psychiatry and neuroscience, there are fundamental gaps in our knowledge about data collection and non-collection (i.e., missing data) in smartphone-based digital phenotyping. In this meta-study using individual-level data from six different studies, we examined accelerometer and GPS sensor data of 211 participants, amounting to 29,500 person-days of observation, using Bayesian hierarchical negative binomial regression with study- and user-level random intercepts. Sensitivity analyses including alternative model specification and stratified models were conducted. We found that iOS users had lower GPS non-collection than Android users. For GPS data, rates of non-collection did not differ by race/ethnicity, education, age, or gender. For accelerometer data, Black participants had higher rates of non-collection, but rates did not differ by sex, education, or age. For both sensors, non-collection increased by 0.5% to 0.9% per week. These results demonstrate the feasibility of using smartphone-based digital phenotyping across diverse populations, for extended periods of time, and within diverse cohorts. As smartphones become increasingly embedded in everyday life, the insights of this study will help guide the design, planning, and analysis of digital phenotyping studies.


Assuntos
Acelerometria/métodos , Coleta de Dados/métodos , Sistemas de Informação Geográfica , Smartphone/instrumentação , Fatores Sociológicos , Adolescente , Adulto , Teorema de Bayes , População Negra , Criança , Cognição , Meio Ambiente , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Social , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-31948836

RESUMO

BACKGROUND: Amygdala overactivity has been frequently observed in patients with depression, as well as in nondepressed relatives of patients with depression. A remaining unanswered question is whether elevated amygdala activity in those with familial risk for depression is related to the presence of subthreshold symptoms or to a trait-level vulnerability for illness. METHODS: To examine this question, functional magnetic resonance imaging data were collected in nondepressed young adults with (family history [FH+]) (n = 27) or without (FH-) (n = 45) a first-degree relative with a history of depression while they viewed images of "looming" or withdrawing stimuli (faces and cars) that varied in salience by virtue of their apparent proximity to the subject. Activation of the amygdala and 2 other regions known to exhibit responses to looming stimuli, the dorsal intraparietal sulcus (DIPS) and ventral premotor cortex (PMv), were measured, as well as levels of resilience, anxiety, and psychotic and depressive symptoms. RESULTS: Compared with the FH- group, the FH+ group exhibited significantly greater responses of the amygdala, but not the dorsal intraparietal sulcus or ventral premotor cortex, to looming face stimuli. Moreover, amygdala responses in the FH+ group were negatively correlated with levels of resilience and unrelated to levels of subthreshold symptoms of psychopathology. CONCLUSIONS: These findings indicate that elevated amygdala activity in nondepressed young adults with a familial history of depression is more closely linked to poor resilience than to current symptom state.


Assuntos
Tonsila do Cerebelo , Depressão , Predisposição Genética para Doença , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Depressão/genética , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Fatores de Risco , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-29529413

RESUMO

BACKGROUND: Delusions are a defining and common symptom of psychotic disorders. Recent evidence suggests that subclinical and clinical delusions may represent distinct stages on a phenomenological and biological continuum. However, few studies have tested whether subclinical psychotic experiences are associated with neural changes that are similar to those observed in clinical psychosis. For example, it is unclear if overactivity of the hippocampus, a replicated finding of neuroimaging studies of schizophrenia, is also present in individuals with subclinical psychotic symptoms. METHODS: To investigate this question, structural and pulsed arterial spin labeling scans were collected in 77 adult participants with no psychiatric history. An anatomical region of interest approach was used to extract resting perfusion of the hippocampus, and 15 other regions, from each individual. A self-report measure of delusional ideation was collected on the day of scanning. RESULTS: The level of delusional thinking (number of beliefs [r = .27, p = .02]), as well as the associated level of distress (r = .29, p = .02), was significantly correlated with hippocampal perfusion (averaged over right and left hemispheres). The correlations remained significant after controlling for age, hippocampal volume, symptoms of depression and anxiety, and image signal-to-noise ratio, and they were confirmed in a voxelwise regression analysis. The same association was observed in the thalamus and parahippocampal, lateral temporal, and cingulate cortices. CONCLUSIONS: Similar to patients with schizophrenia, non-help-seeking individuals show elevated perfusion of a network of limbic regions in association with delusional beliefs.


Assuntos
Delusões/fisiopatologia , Hipocampo/fisiopatologia , Rede Nervosa/fisiopatologia , Transtornos Psicóticos/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/diagnóstico , Esquizofrenia/fisiopatologia , Lobo Temporal/fisiopatologia , Pensamento/fisiologia
10.
Neuroimage Clin ; 9: 233-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26484048

RESUMO

Schizophrenia is associated with subtle abnormalities in day-to-day social behaviors, including a tendency in some patients to "keep their distance" from others in physical space. The neural basis of this abnormality, and related changes in social functioning, is unknown. Here we examined, in schizophrenic patients and healthy control subjects, the functioning of a parietal-frontal network involved in monitoring the space immediately surrounding the body ("personal space"). Using fMRI, we found that one region of this network, the dorsal intraparietal sulcus (DIPS), was hyper-responsive in schizophrenic patients to face stimuli appearing to move towards the subjects, intruding into personal space. This hyper-responsivity was predicted both by the size of personal space (which was abnormally elevated in the schizophrenia group) and the severity of negative symptoms. In contrast, in a second study, the activity of two lower-level visual areas that send information to DIPS (the fusiform face area and middle temporal area) was normal in schizophrenia. Together, these findings suggest that changes in parietal-frontal networks that support the sensory-guided initiation of behavior, including actions occurring in the space surrounding the body, contribute to social dysfunction and negative symptoms in schizophrenia.


Assuntos
Lobo Frontal/patologia , Lobo Parietal/patologia , Espaço Pessoal , Esquizofrenia/patologia , Comportamento Social , Adulto , Atenção/fisiologia , Mapeamento Encefálico , Feminino , Lobo Frontal/irrigação sanguínea , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/patologia , Testes Neuropsicológicos , Lobo Parietal/irrigação sanguínea , Estimulação Luminosa , Adulto Jovem
11.
PLoS One ; 9(5): e97466, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24816735

RESUMO

BACKGROUND: Previous studies have shown that the activity of the amygdala is elevated in people experiencing clinical and subclinical levels of anxiety and depression (negative affect). It has been proposed that a reduction in inhibitory input to the amygdala from the prefrontal cortex and resultant over-activity of the amygdala underlies this association. Prior studies have found relationships between negative affect and 1) amygdala over-activity and 2) reduced amygdala-prefrontal connectivity. However, it is not known whether elevated amygdala activity is associated with decreased amygdala-prefrontal connectivity during negative affect states. METHODS: Here we used resting-state arterial spin labeling (ASL) and blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) in combination to test this model, measuring the activity (regional cerebral blood flow, rCBF) and functional connectivity (correlated fluctuations in the BOLD signal) of one subregion of the amygdala with strong connections with the prefrontal cortex, the basolateral nucleus (BLA), and subsyndromal anxiety levels in 38 healthy subjects. RESULTS: BLA rCBF was strongly correlated with anxiety levels. Moreover, both BLA rCBF and anxiety were inversely correlated with the strength of the functional coupling of the BLA with the caudal ventromedial prefrontal cortex. Lastly, BLA perfusion was found to be a mediator of the relationship between BLA-prefrontal connectivity and anxiety. CONCLUSIONS: These results show that both perfusion of the BLA and a measure of its functional coupling with the prefrontal cortex directly index anxiety levels in healthy subjects, and that low BLA-prefrontal connectivity may lead to increased BLA activity and resulting anxiety. Thus, these data provide key evidence for an often-cited circuitry model of negative affect, using a novel, multi-modal imaging approach.


Assuntos
Afeto/fisiologia , Tonsila do Cerebelo/fisiologia , Conectoma , Depressão/fisiopatologia , Modelos Biológicos , Córtex Pré-Frontal/fisiologia , Humanos , Imageamento por Ressonância Magnética , Oxigênio/sangue , Marcadores de Spin
12.
Soc Cogn Affect Neurosci ; 9(3): 273-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23160817

RESUMO

Neuroimaging studies have demonstrated associations between delusions in psychotic disorders and abnormalities of brain areas involved in social cognition, including medial prefrontal cortex (MPFC), posterior cingulate cortex, and lateral temporal cortex (LTC). General population studies have linked subclinical delusional thinking to impaired social cognition, raising the question of whether a specific pattern of brain activity during social perception is associated with delusional beliefs. Here, we tested the hypothesis that subclinical delusional thinking is associated with changes in neural function, while subjects made judgments about themselves or others ['social reflection' (SR)]. Neural responses during SR and non-social tasks, as well as resting-state activity, were measured using functional magnetic resonance imaging in 22 healthy subjects. Delusional thinking was measured using the Peters et al. Delusions Inventory. Delusional thinking was negatively correlated with responses of the left LTC during SR (r = -0.61, P = 0.02, Bonferroni corrected), and connectivity between the left LTC and left ventral MPFC, and was positively correlated with connectivity between the left LTC and the right middle frontal and inferior temporal cortices. Thus, delusional thinking in the general population may be associated with reduced activity and aberrant functional connectivity of cortical areas involved in SR.


Assuntos
Mapeamento Encefálico , Vias Neurais/fisiologia , Comportamento Social , Lobo Temporal/fisiologia , Adulto , Idoso , Transtornos Cognitivos/fisiopatologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
13.
Schizophr Res ; 157(1-3): 292-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24951401

RESUMO

BACKGROUND: Deficits in the capacity to reflect about the self and others ("social reflection" [SR]) have been identified in schizophrenia, as well as in people with a genetic or clinical risk for the disorder. However, the neural underpinnings of these abnormalities are incompletely understood. METHODS: Responses of a network of brain regions known to be involved in self and other processing (e.g., medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC), and superior temporal gyrus (STG)) were measured during SR in 16 first-degree, non-psychotic relatives (RELS) of schizophrenia patients and 16 healthy controls (CONS). Because of prior evidence linking dysfunction in this network and delusions, associations between SR-related responses of this network and subclinical delusions (measured using the Peters et al. Delusions Inventory) were also examined. RESULTS: Compared with CONS, RELS showed significantly less SR-related activity of the right and left PCC and STG. Moreover, response magnitudes were negatively correlated with levels of delusional thinking across both groups. CONCLUSIONS: These findings suggest that aberrant function of the neural circuitry underpinning SR is associated with the genetic liability to schizophrenia and confers vulnerability to delusional beliefs.


Assuntos
Encéfalo/fisiopatologia , Delusões/fisiopatologia , Família , Esquizofrenia , Percepção Social , Pensamento/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Testes Neuropsicológicos , Tempo de Reação , Esquizofrenia/genética , Esquizofrenia/fisiopatologia
14.
Schizophr Res ; 143(1): 150-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23201307

RESUMO

Patients with schizophrenia may have altered pain perception, as suggested by clinical reports of pain insensitivity, and recent neuroimaging findings. Here, we examined neural responses to an aversive electrical stimulus and the immediate anticipation of such a stimulus using fMRI and a classical conditioning paradigm, which involved pairing an electrical shock with a neutral photograph. Fifteen men with schizophrenia and 13 healthy men, matched for demographic characteristics, electrical stimulation level and scan movement, were studied. The shock induced robust responses in midbrain, thalamus, cingulate gyrus, insula and somatosensory cortex in both groups. However, compared to controls, the schizophrenic patients displayed significantly lower activation of the middle insula (p(FWE)=0.002, T=5.72, cluster size=24 voxels). Moreover, the lack of insula reactivity in the schizophrenia group was predicted by the magnitude of positive symptoms (r=-0.46, p=0.04). In contrast, there were no significant differences between the two groups in the magnitude of neural responses during anticipation of the shock. These findings provide support for the existence of a basic deficit in interoceptive perception in schizophrenia, which could play a role in the generation and/or maintenance of psychotic states.


Assuntos
Córtex Cerebral/fisiopatologia , Medo/psicologia , Percepção da Dor/fisiologia , Esquizofrenia/patologia , Psicologia do Esquizofrênico , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Córtex Cerebral/irrigação sanguínea , Condicionamento Clássico , Estimulação Elétrica/efeitos adversos , Resposta Galvânica da Pele/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Esquizofrenia/fisiopatologia , Adulto Jovem
15.
Arch Gen Psychiatry ; 69(9): 893-903, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22945619

RESUMO

CONTEXT Abnormalities in associative memory processes, such as Pavlovian fear conditioning and extinction, have been observed in schizophrenia. The retrieval of fear extinction memories (safety signals) may be particularly affected; although schizophrenic patients can extinguish conditioned fear, they show a deficit in retrieving fear extinction memories after a delay. The neurobiological basis of this abnormality is unknown, but clues have emerged from studies in rodents and humans demonstrating that the ventromedial prefrontal cortex (vmPFC) is a key mediator of extinction memory retrieval. OBJECTIVE To measure autonomic and neural responses during the acquisition and extinction of conditioned fear and the delayed recall of fear and extinction memories in patients with schizophrenia and healthy control participants. DESIGN Cross-sectional case control, functional magnetic resonance imaging study. SETTING Academic medical center. PARTICIPANTS Twenty schizophrenic patients and 17 healthy control participants demographically matched to the patient group. MAIN OUTCOME MEASURES Skin conductance and blood oxygen level-dependent responses. RESULTS During fear conditioning, schizophrenic patients showed blunted autonomic responses and abnormal blood oxygen level-dependent responses, relative to control participants, within the posterior cingulate gyrus, hippocampus, and other regions. Several of these abnormalities were linked to negative symptoms. During extinction learning, patients with schizophrenia and control participants showed comparable autonomic and neural responses. Twenty-four hours after the learning phases, the control subjects exhibited decreased fear and increased vmPFC responses in the extinction (safe) context as expected, indicating successful retention of the extinction memory. In contrast, the schizophrenic patients showed inappropriately elevated fear and poor vmPFC responses in the safe context. CONCLUSION Failure of extinction memory retrieval in schizophrenia is associated with vmPFC dysfunction. In future studies, abnormalities in fear learning and extinction recall may serve as quantitative phenotypes that can be linked to genetic, symptom, or outcome profiles in schizophrenia and those at risk for the disorder.


Assuntos
Encéfalo/fisiopatologia , Condicionamento Clássico/fisiologia , Sinais (Psicologia) , Extinção Psicológica/fisiologia , Medo/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Rememoração Mental/fisiologia , Segurança , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Tonsila do Cerebelo/fisiopatologia , Nível de Alerta/fisiologia , Sistema Nervoso Autônomo/fisiopatologia , Mapeamento Encefálico , Estudos de Casos e Controles , Estudos Transversais , Dominância Cerebral/fisiologia , Resposta Galvânica da Pele/fisiologia , Giro do Cíngulo/fisiopatologia , Humanos , Oxigênio/sangue , Córtex Pré-Frontal/fisiopatologia , Retenção Psicológica/fisiologia , Esquizofrenia/diagnóstico
17.
Biol Psychiatry ; 69(5): 415-23, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21144498

RESUMO

BACKGROUND: Deficits in social cognition, including impairments in self-awareness, contribute to the overall functional disability associated with schizophrenia. Studies in healthy subjects have shown that social cognitive functions, including self-reflection, rely on the medial prefrontal cortex (mPFC) and posterior cingulate gyrus, and these regions exhibit highly correlated activity during "resting" states. In this study, we tested the hypothesis that patients with schizophrenia show dysfunction of this network during self-reflection and that this abnormal activity is associated with changes in the strength of resting-state correlations between these regions. METHODS: Activation during self-reflection and control tasks was measured with functional magnetic resonance imaging in 19 patients with schizophrenia and 20 demographically matched control subjects. In addition, the resting-state functional connectivity of midline cortical areas showing abnormal self-reflection-related activation in schizophrenia was measured. RESULTS: Compared with control subjects, the schizophrenia patients demonstrated lower activation of the right ventral mPFC and greater activation of the mid/posterior cingulate gyri bilaterally during self-reflection, relative to a control task. A similar pattern was seen during overall social reflection. In addition, functional connectivity between the portion of the left mid/posterior cingulate gyrus showing abnormally elevated activity during self-reflection in schizophrenia, and the dorsal anterior cingulate gyrus was lower in the schizophrenia patients compared with control subjects. CONCLUSIONS: Schizophrenia is associated with an anterior-to-posterior shift in introspection-related activation, as well as changes in functional connectivity, of the midline cortex. These findings provide support for the hypothesis that aberrant midline cortical function contributes to social cognitive impairment in schizophrenia.


Assuntos
Córtex Cerebral/fisiopatologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Afeto/fisiologia , Córtex Cerebral/patologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Ego , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Processos Mentais/fisiologia , Vias Neurais/fisiologia , Oxigênio/sangue , Estimulação Luminosa , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia , Tempo de Reação/fisiologia , Leitura , Esquizofrenia/patologia , Autoimagem , Percepção Social
18.
Pers Soc Psychol Bull ; 36(8): 1101-14, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20693387

RESUMO

Seventy-seven undergraduates, primed for autonomous or controlled motivation, were videotaped and physiologically monitored during a stressful interview and subsequent speech. Interview videotapes were coded for behavioral measures of threat response; speech videotapes were coded for performance. It was hypothesized that relative to controlled motivation, autonomous motivation would decrease interview threat response and enhance speech performance, and that threat response would mediate the effect of motivation on performance. Results support the prediction across measures of verbal, paralinguistic, smiling, vocal fundamental frequency, and cardiovascular response. Autonomously primed participants continued to show less cardiovascular threat throughout the later speech and gave better speeches. Finally, speech performance was mediated by interview threat response. Results demonstrate that relative to controlled motivation, autonomous motivation lowers threat response, which enhances performance.


Assuntos
Mecanismos de Defesa , Motivação/fisiologia , Autonomia Pessoal , Estresse Psicológico/psicologia , Adolescente , Análise de Variância , Débito Cardíaco , Sinais (Psicologia) , Feminino , Humanos , Entrevistas como Assunto , Masculino , Teoria Psicológica , Sorriso/psicologia , Estudantes/psicologia , Análise e Desempenho de Tarefas , Comportamento Verbal
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