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1.
Front Psychiatry ; 11: 467, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32528330

RESUMEN

Pranayama refers to a set of yoga breathing exercises. Recent evidence suggests that the practice of pranayama has positive effects on measures of clinical stress and anxiety. This study explored the impact of a Bhastrika pranayama training program on emotion processing, anxiety, and affect. We used a randomized controlled trial design with thirty healthy young adults assessed at baseline and after 4 weeks of pranayama practices. Two functional magnetic resonance imaging (MRI) protocols were used both at baseline and post-intervention: an emotion task as well as a resting-state acquisition. Our results suggest that pranayama significantly decreased states of anxiety and negative affect. The practice of pranayama also modulated the activity of brain regions involved in emotional processing, particularly the amygdala, anterior cingulate, anterior insula, and prefrontal cortex. Resting-state functional MRI (fMRI) showed significantly reduced functional connectivity involving the anterior insula and lateral portions of the prefrontal cortex. Correlation analysis revealed that changes in connectivity between the ventrolateral prefrontal cortex and the right anterior insula were associated with changes in anxiety. Although it should be noted that these analyses were preliminary and exploratory, it provides the first evidence that 4 weeks of B. pranayama significantly reduce the levels of anxiety and negative affect, and that these changes are associated with the modulation of activity and connectivity in brain areas involved in emotion processing, attention, and awareness. The study was registered at https://www.ensaiosclinicos.gov.br/rg/RBR-2gv5c2/(RBR-2gv5c2).

2.
Psychol Med ; 49(4): 655-663, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29903051

RESUMEN

BACKGROUND: Recent open-label trials show that psychedelics, such as ayahuasca, hold promise as fast-onset antidepressants in treatment-resistant depression. METHODS: To test the antidepressant effects of ayahuasca, we conducted a parallel-arm, double-blind randomized placebo-controlled trial in 29 patients with treatment-resistant depression. Patients received a single dose of either ayahuasca or placebo. We assessed changes in depression severity with the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Hamilton Depression Rating scale at baseline, and at 1 (D1), 2 (D2), and 7 (D7) days after dosing. RESULTS: We observed significant antidepressant effects of ayahuasca when compared with placebo at all-time points. MADRS scores were significantly lower in the ayahuasca group compared with placebo at D1 and D2 (p = 0.04), and at D7 (p < 0.0001). Between-group effect sizes increased from D1 to D7 (D1: Cohen's d = 0.84; D2: Cohen's d = 0.84; D7: Cohen's d = 1.49). Response rates were high for both groups at D1 and D2, and significantly higher in the ayahuasca group at D7 (64% v. 27%; p = 0.04). Remission rate showed a trend toward significance at D7 (36% v. 7%, p = 0.054). CONCLUSIONS: To our knowledge, this is the first controlled trial to test a psychedelic substance in treatment-resistant depression. Overall, this study brings new evidence supporting the safety and therapeutic value of ayahuasca, dosed within an appropriate setting, to help treat depression. This study is registered at http://clinicaltrials.gov (NCT02914769).


Asunto(s)
Antidepresivos/uso terapéutico , Banisteriopsis , Trastorno Depresivo Resistente al Tratamiento/tratamiento farmacológico , Alucinógenos/uso terapéutico , Fitoterapia/métodos , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Escalas de Valoración Psiquiátrica , Factores de Tiempo , Resultado del Tratamiento
3.
Int J Neurosci ; 128(10): 966-974, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29490535

RESUMEN

BACKGROUND: Mirror therapy (MT) is becoming an alternative rehabilitation strategy for various conditions, including stroke. Although recent studies suggest the positive benefit of MT in chronic stroke motor recovery, little is known about its neural mechanisms. PURPOSE: To identify functional brain changes induced by a single MT intervention in ischemic stroke survivors, assessed by both transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI). MATERIALS AND METHODS: TMS and fMRI were used to investigate 15 stroke survivors immediately before and after a single 30-min MT session. RESULTS: We found statistically significant increase in post-MT motor evoked potential (MEP) amplitude (increased excitability) from the affected primary motor cortex (M1), when compared to pre-MT MEP. Post-MT fMRI maps were associated with a more organized and constrained pattern, with a more focal M1 activity within the affected hemisphere after MT, limited to the cortical area of hand representation. Furthermore, we find a change in the balance of M1 activity toward the affected hemisphere. In addition, significant correlation was found between decreased fMRI ß-values and increased MEP amplitude post-MT, in the affected hemisphere. CONCLUSION: Our study suggests that a single MT intervention in stroke survivors is related to increased MEP of the affected limb, and a more constrained activity of the affected M1, as if activity had become more constrained and limited to the affected hemisphere.


Asunto(s)
Isquemia Encefálica/rehabilitación , Potenciales Evocados Motores/fisiología , Corteza Motora/fisiopatología , Evaluación de Resultado en la Atención de Salud , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/terapia , Extremidad Superior/fisiopatología , Anciano , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/fisiopatología , Enfermedad Crónica/rehabilitación , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Motora/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/fisiopatología , Estimulación Magnética Transcraneal
4.
PLoS One ; 10(2): e0118143, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25693169

RESUMEN

The experiences induced by psychedelics share a wide variety of subjective features, related to the complex changes in perception and cognition induced by this class of drugs. A remarkable increase in introspection is at the core of these altered states of consciousness. Self-oriented mental activity has been consistently linked to the Default Mode Network (DMN), a set of brain regions more active during rest than during the execution of a goal-directed task. Here we used fMRI technique to inspect the DMN during the psychedelic state induced by Ayahuasca in ten experienced subjects. Ayahuasca is a potion traditionally used by Amazonian Amerindians composed by a mixture of compounds that increase monoaminergic transmission. In particular, we examined whether Ayahuasca changes the activity and connectivity of the DMN and the connection between the DMN and the task-positive network (TPN). Ayahuasca caused a significant decrease in activity through most parts of the DMN, including its most consistent hubs: the Posterior Cingulate Cortex (PCC)/Precuneus and the medial Prefrontal Cortex (mPFC). Functional connectivity within the PCC/Precuneus decreased after Ayahuasca intake. No significant change was observed in the DMN-TPN orthogonality. Altogether, our results support the notion that the altered state of consciousness induced by Ayahuasca, like those induced by psilocybin (another serotonergic psychedelic), meditation and sleep, is linked to the modulation of the activity and the connectivity of the DMN.


Asunto(s)
Banisteriopsis/química , Conectoma/métodos , Trastornos de la Conciencia/inducido químicamente , Giro del Cíngulo/fisiopatología , Alucinógenos/administración & dosificación , Corteza Prefrontal/fisiopatología , Adulto , Trastornos de la Conciencia/fisiopatología , Femenino , Alucinógenos/efectos adversos , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Prefrontal/efectos de los fármacos , Psilocibina/farmacología , Adulto Joven
5.
Epilepsy Behav ; 38: 71-80, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24374054

RESUMEN

Functional magnetic resonance imaging (fMRI) has just completed 20 years of existence. It currently serves as a research tool in a broad range of human brain studies in normal and pathological conditions, as is the case of epilepsy. To date, most fMRI studies aimed at characterizing brain activity in response to various active paradigms. More recently, a number of strategies have been used to characterize the low-frequency oscillations of the ongoing fMRI signals when individuals are at rest. These datasets have been largely analyzed in the context of functional connectivity, which inspects the covariance of fMRI signals from different areas of the brain. In addition, resting state fMRI is progressively being used to evaluate complex network features of the brain. These strategies have been applied to a number of different problems in neuroscience, which include diseases such as Alzheimer's, schizophrenia, and epilepsy. Hence, we herein aimed at introducing the subject of complex network and how to use it for the analysis of fMRI data. This appears to be a promising strategy to be used in clinical epilepsy. Therefore, we also review the recent literature that has applied these ideas to the analysis of fMRI data in patients with epilepsy.


Asunto(s)
Mapeo Encefálico/métodos , Epilepsia/fisiopatología , Imagen por Resonancia Magnética/métodos , Modelos Neurológicos , Red Nerviosa/fisiopatología , Humanos
6.
Rev. bras. crescimento desenvolv. hum ; 17(2): 37-44, ago. 2007. tab
Artículo en Portugués | Index Psicología - Revistas | ID: psi-54922

RESUMEN

Este artigo tem como objetivo identificar, através da percepção materna, o desenvolvimento de crianças atendidas no primeiro ano de vida em serviços públicos de saúde do Brasil. Em entrevista com as mães, foram levantados sinais de desenvolvimento: firmar a cabeça, sentar, engatinhar, andar com ajuda ou sozinha, falar e dentição de 5655 crianças. As respostas categóricas (sim/não) foram avaliadas segundo associação com: idade e escolaridade maternas, idade gestacional no parto, peso ao nascer, estado nutricional e anemia da criança, aleitamento materno e uso de chupeta. Os resultados revelaram que a maior proporção de crianças apresenta-se atrasada em relação aos padrões estabelecidos pelo Ministério da Saúde para o desenvolvimento neuromotor e dentição. A prematuridade foi o fator mais freqüentemente associado a sinais de desenvolvimento não atingidos e a dentição foi o sinal mais sensível às mesmas variáveis. Verificou-se que parte dos resultados negativos talvez sejam conseqüência da dificuldade materna em identificar os sinais subjetivos de desenvolvimento. Sugere-se que um levantamento dos sinais de desenvolvimento seja realizado por profissionais treinados permitindo verificar critérios e/ou intervenções adequadas para modificar a situação encontrada(AU)


This article aims to estimate, through maternal perception, the prevalence of development signs, and determine associated risk factors among infants receiving routine health care in public clinics. The cross-sectional study included 5655 infants in the first year of life. The information regarding the child was obtained from the mother/caregiver by means of an interview. The development signs studied were: sustaining the head, seating, crawling, walking with some help or by itself, speaking, and also teething. The categorical answers (yes/no) were evaluated according to: maternal age and schooling, gestational age at childbirth, birth weight, child's nutritional status and anemia, breast-feeding, and use of pacifier. Results showed that most of the children are delayed according to the standards of neuromotor development and teething established by the Ministry of Health. Prematurity was the factor most often associated with non-reached development signs, and teething was the sign most frequently associated with the selected variables. It was verified that part of the negative results may be a consequence of the maternal difficulty in identifying subjective development signs. It is suggested that a survey to identify development signs is conducted by trained professionals to check criteria and/or adequate interventions to change the observed results.(AU)

7.
Rev. bras. crescimento desenvolv. hum ; 17(2): 37-44, abr.-jun. 2007. tab
Artículo en Portugués | LILACS | ID: lil-481792

RESUMEN

Este artigo tem como objetivo identificar, através da percepção materna, o desenvolvimento de crianças atendidas no primeiro ano de vida em serviços públicos de saúde do Brasil. Em entrevista com as mães, foram levantados sinais de desenvolvimentos: firmar a cabeça, sentar, engatinhar, andar com ajuda ou sozinha, falar e dentição 5655 crianças. As respostas categóricas (sim/não) foram avaliadas segundo associação com: idade e escolaridades maternas, idade gestacional no parto, peso ao nascer, estado nutricional e anemia da criança, aleitamento materno e uso de chupeta. Os resultados revelaram que a maior proporção de crianças apresenta-se atrasada em relação aos padrões estabelecidos pelo Ministério da Saúde para o desenvolvimento neuromotor e dentição. A prematuridade foi o fator mais freqüentemente associado a sinais de desenvolvimentos não atingidos e a dentição foi o sinal mais sensível às mesmas variáveis. Verificou-se que parte dos resultados negativos talvez sejam conseqüência da dificuldade materna em identificar os sinais subjetivos de desenvolvimento. Sugere-se que um levantamento dos sinais de desenvolvimento seja realizado por profissionais treinados permitindo verificar critérios e/ou intervenções adequadas para modificar a situação encontrada.


This article aims to estimate, through maternal perception, the prevalence of development signs, and determine associated risk factors among infants receiving routine health care in public clinics. The cross-sectional study included 5655 infants in the first year of life. The information regarding the child was obtained from the mother/caregiver by means of an interview. The development signs studied were: sustaining the head, seating, crawling, walking with some help or by itself, speaking, and also teething. The categorical answers (yes/no) were evaluated according to: maternal age and schooling, gestational age at childbirth, birth weight, child's nutritional status and anemia, breast-feeding, and use of pacifier. Results showed that most of the children are delayed according to the standards of neuromotor development and teething established by the Ministry of Health. Prematurity was the factor most often associated with non-reached development signs, and teething was the sign most frequently associated with the selected variables. It was verified that part of the negative results may be a consequence of the maternal difficulty in identifying subjective development signs. It is suggested that a survey to identify development signs is conducted by trained professionals to check criteria and/or adequate interventions to change the observed results.


Asunto(s)
Desarrollo Infantil , Dentición , Servicios de Salud
8.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;64(4): 895-898, dez. 2006. ilus
Artículo en Inglés, Portugués | LILACS | ID: lil-439738

RESUMEN

The increase of relative cerebral blood flow (rCBF) may contribute for a change in blood oxygenation level dependent signal (BOLD). The main purpose of this study is to investigate some aspects of perfusional alterations in the human brain in response to a uniform stimulation: hypercapnia induced by breath holding. It was observed that the BOLD signal increased globally during hypercapnia and that it is correlated with the time of breath holding. This signal increase shows a clear distinction between gray and white matter, being greater in the grey matter.


O aumento relativo do fluxo cerebral sangüíneo (relative Cerebral Blood Flow - rCBF) pode contribuir para uma mudança no sinal dependente da oxigenação do sangue (Blood Oxygenation Level Dependent - BOLD). O objetivo principal deste trabalho foi estudar alguns aspectos da alteração perfusional no cérebro humano em resposta a um estímulo uniforme: hipercapnia, causada por um estado de apnéia induzida. Foi observado um aumento global no sinal BOLD durante a hipercapnia. Este aumento é correlacionado com a duração da apnéia e mostra uma clara distinção entre a substância branca e cinzenta, sendo maior na substância cinzenta.


Asunto(s)
Femenino , Humanos , Masculino , Encéfalo/irrigación sanguínea , Hipercapnia/fisiopatología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Oxígeno/sangre , Mapeo Encefálico , Velocidad del Flujo Sanguíneo/fisiología , Encéfalo/fisiopatología , Respiración , Flujo Sanguíneo Regional/fisiología
9.
Arq Neuropsiquiatr ; 64(4): 895-8, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17220991

RESUMEN

The increase of relative cerebral blood flow (rCBF) may contribute for a change in blood oxygenation level dependent signal (BOLD). The main purpose of this study is to investigate some aspects of perfusional alterations in the human brain in response to a uniform stimulation: hypercapnia induced by breath holding. It was observed that the BOLD signal increased globally during hypercapnia and that it is correlated with the time of breath holding. This signal increase shows a clear distinction between gray and white matter, being greater in the grey matter.


Asunto(s)
Encéfalo/irrigación sanguínea , Hipercapnia/fisiopatología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Oxígeno/sangre , Velocidad del Flujo Sanguíneo/fisiología , Encéfalo/fisiopatología , Mapeo Encefálico , Femenino , Humanos , Masculino , Flujo Sanguíneo Regional/fisiología , Respiración
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