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1.
Psychon Bull Rev ; 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302789

RESUMEN

Mindfulness has been linked to a range of positive social-emotional and cognitive outcomes, but the underlying mechanisms are unclear. As one of the few traits or dispositions that are associated with both affective and cognitive benefits, we asked whether mindfulness is associated with affective and cognitive outcomes through a shared, unitary process or through two dissociable processes. We examined this in adolescents using behavioral measures and also reanalyzed previously reported neuroimaging findings relating mindfulness training to either affect (negative emotion, stress) or cognition (sustained attention). Using multivariate regression analyses, our findings suggest that the relationships between dispositional mindfulness and affective and cognitive processes are behaviorally dissociable and converge with neuroimaging data indicating that mindfulness modulates affect and cognition through separate neural pathways. These findings support the benefits of trait mindfulness on both affective and cognitive processes, and reveal that those benefits are at least partly dissociable in the mind and brain.

2.
World J Biol Psychiatry ; 25(2): 95-105, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37786280

RESUMEN

OBJECTIVE: During hypnosis, significant changes in the BOLD signal associated with the anterior default mode network (DMN) and prefrontal attentional systems have been reported as evidence of dissociation defined since Charcot. However, it remains uncertain whether these changes are mainly attributable to the hypnotic state per se or to the target suggestions used to verify subject's state during neuroimaging studies. The aim of the present study is to evidence the brain in hypnosis, contrasting the common resting state versus neutral hypnosis (hypnosis in the absence of target suggestions). METHODS: Twenty-four healthy right-handed volunteers (age 28.3 y.o., 12 females) rated moderate hypnotic responsiveness underwent resting state fMRI at 3.0 T in two sessions, once in neutral hypnosis and the other in the common resting state. Each subject's functional data were analyzed for low-frequency BOLD signal correlations seed-to-voxel for the whole brain in the first-level analysis, and seed-to-voxel in a second-level analysis to estimate group results using seeds for five resting state networks: the default mode (DMN), the central executive (CEN), the salience (SaN), the dorso-lateral attention (DAN), and the sensorimotor (SMN) networks. RESULTS: In general, all network maps of the hypnotic condition presented higher connectivity than those of the resting condition. However, only contrasts for the DAN, SaN, and SMN were statistically significant, including correlated out-of-the-network regions. CONCLUSION: Parietal and occipital regions displayed increased connectivity across networks, implying dissociation from the frontal cortices. This is the first fMRI intrinsic study of hypnosis without target suggestion.


Asunto(s)
Hipnosis , Imagen por Resonancia Magnética , Femenino , Humanos , Adulto , Imagen por Resonancia Magnética/métodos , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Hipnóticos y Sedantes
3.
BMC Psychiatry ; 23(1): 757, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37848857

RESUMEN

BACKGROUND: Adolescence is characterized by a heightened vulnerability for Major Depressive Disorder (MDD) onset, and currently, treatments are only effective for roughly half of adolescents with MDD. Accordingly, novel interventions are urgently needed. This study aims to establish mindfulness-based real-time fMRI neurofeedback (mbNF) as a non-invasive approach to downregulate the default mode network (DMN) in order to decrease ruminatory processes and depressive symptoms. METHODS: Adolescents (N = 90) with a current diagnosis of MDD ages 13-18-years-old will be randomized in a parallel group, two-arm, superiority trial to receive either 15 or 30 min of mbNF with a 1:1 allocation ratio. Real-time neurofeedback based on activation of the frontoparietal network (FPN) relative to the DMN will be displayed to participants via the movement of a ball on a computer screen while participants practice mindfulness in the scanner. We hypothesize that within-DMN (medial prefrontal cortex [mPFC] with posterior cingulate cortex [PCC]) functional connectivity will be reduced following mbNF (Aim 1: Target Engagement). Additionally, we hypothesize that participants in the 30-min mbNF condition will show greater reductions in within-DMN functional connectivity (Aim 2: Dosing Impact on Target Engagement). Aim 1 will analyze data from all participants as a single-group, and Aim 2 will leverage the randomized assignment to analyze data as a parallel-group trial. Secondary analyses will probe changes in depressive symptoms and rumination. DISCUSSION: Results of this study will determine whether mbNF reduces functional connectivity within the DMN among adolescents with MDD, and critically, will identify the optimal dosing with respect to DMN modulation as well as reduction in depressive symptoms and rumination. TRIAL REGISTRATION: This study has been registered with clinicaltrials.gov, most recently updated on July 6, 2023 (trial identifier: NCT05617495).


Asunto(s)
Trastorno Depresivo Mayor , Atención Plena , Neurorretroalimentación , Humanos , Adolescente , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/terapia , Imagen por Resonancia Magnética/métodos , Neurorretroalimentación/métodos , Giro del Cíngulo/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos
4.
Mol Psychiatry ; 28(6): 2540-2548, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36991135

RESUMEN

Adolescents experience alarmingly high rates of major depressive disorder (MDD), however, gold-standard treatments are only effective for ~50% of youth. Accordingly, there is a critical need to develop novel interventions, particularly ones that target neural mechanisms believed to potentiate depressive symptoms. Directly addressing this gap, we developed mindfulness-based fMRI neurofeedback (mbNF) for adolescents that aims to reduce default mode network (DMN) hyperconnectivity, which has been implicated in the onset and maintenance of MDD. In this proof-of-concept study, adolescents (n = 9) with a lifetime history of depression and/or anxiety were administered clinical interviews and self-report questionnaires, and each participant's DMN and central executive network (CEN) were personalized using a resting state fMRI localizer. After the localizer scan, adolescents completed a brief mindfulness training followed by a mbNF session in the scanner wherein they were instructed to volitionally reduce DMN relative to CEN activation by practicing mindfulness meditation. Several promising findings emerged. First, mbNF successfully engaged the target brain state during neurofeedback; participants spent more time in the target state with DMN activation lower than CEN activation. Second, in each of the nine adolescents, mbNF led to significantly reduced within-DMN connectivity, which correlated with post-mbNF increases in state mindfulness. Last, a reduction of within-DMN connectivity mediated the association between better mbNF performance and increased state mindfulness. These findings demonstrate that personalized mbNF can effectively and non-invasively modulate the intrinsic networks associated with the emergence and persistence of depressive symptoms during adolescence.


Asunto(s)
Trastorno Depresivo Mayor , Atención Plena , Neurorretroalimentación , Humanos , Adolescente , Trastorno Depresivo Mayor/terapia , Proyectos Piloto , Imagen por Resonancia Magnética , Red en Modo Predeterminado , Encéfalo/fisiología , Mapeo Encefálico , Vías Nerviosas/fisiología
5.
Hum Brain Mapp ; 41(18): 5356-5369, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-32969562

RESUMEN

Mindfulness training can enhance cognitive control, but the neural mechanisms underlying such enhancement in children are unknown. Here, we conducted a randomized controlled trial (RCT) with sixth graders (mean age 11.76 years) to examine the impact of 8 weeks of school-based mindfulness training, relative to coding training as an active control, on sustained attention and associated resting-state functional brain connectivity. At baseline, better performance on a sustained-attention task correlated with greater anticorrelation between the default mode network (DMN) and right dorsolateral prefrontal cortex (DLPFC), a key node of the central executive network. Following the interventions, children in the mindfulness group preserved their sustained-attention performance (i.e., fewer lapses of attention) and preserved DMN-DLPFC anticorrelation compared to children in the active control group, who exhibited declines in both sustained attention and DMN-DLPFC anticorrelation. Further, change in sustained-attention performance correlated with change in DMN-DLPFC anticorrelation only within the mindfulness group. These findings provide the first causal link between mindfulness training and both sustained attention and associated neural plasticity. Administered as a part of sixth graders' school schedule, this RCT supports the beneficial effects of school-based mindfulness training on cognitive control.


Asunto(s)
Atención/fisiología , Conectoma , Red en Modo Predeterminado/fisiología , Corteza Prefontal Dorsolateral/fisiología , Función Ejecutiva/fisiología , Atención Plena , Red Nerviosa/fisiología , Plasticidad Neuronal/fisiología , Niño , Red en Modo Predeterminado/diagnóstico por imagen , Corteza Prefontal Dorsolateral/diagnóstico por imagen , Femenino , Humanos , Masculino , Red Nerviosa/diagnóstico por imagen , Desempeño Psicomotor/fisiología
6.
Psychiatry Res ; 284: 112770, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32004893

RESUMEN

Auditory hallucinations (AHs) are one of the most distressing symptoms of schizophrenia (SZ) and are often resistant to medication. Imaging studies of individuals with SZ show hyperactivation of the default mode network (DMN) and the superior temporal gyrus (STG). Studies in SZ show DMN hyperconnectivity and reduced anticorrelation between DMN and the central executive network (CEN). DMN hyperconnectivity has been associated with positive symptoms such as AHs while reduced DMN anticorrelations with cognitive impairment. Using real-time fMRI neurofeedback (rt-fMRI-NFB) we trained SZ patients to modulate DMN and CEN networks. Meditation is effective in reducing AHs in SZ and to modulate brain network integration and increase DMN anticorrelations. Consequently, patients were provided with meditation strategies to enhance their abilities to modulate DMN/CEN. Results show a reduction of DMN hyperconnectivity and increase in DMNCEN anticorrelation. Furthermore, the change in individual DMN connectivity significantly correlated with reductions in AHs. This is the first time that meditation enhanced through rt-fMRI-NFB is used to reduce AHs in SZ. Moreover, it provides the first empirical evidence for a direct causal relation between meditation enhanced rt-fMRI-NFB modulation of DMNCEN activity and post-intervention modulation of resting state networks ensuing in reductions in frequency and severity of AHs.


Asunto(s)
Encéfalo/diagnóstico por imagen , Alucinaciones/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Red Nerviosa/diagnóstico por imagen , Neurorretroalimentación/métodos , Esquizofrenia/diagnóstico por imagen , Adulto , Mapeo Encefálico/métodos , Femenino , Alucinaciones/terapia , Humanos , Masculino , Meditación/métodos , Meditación/psicología , Persona de Mediana Edad , Prueba de Estudio Conceptual , Descanso , Esquizofrenia/terapia
7.
Behav Neurosci ; 133(6): 569-585, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31448928

RESUMEN

The impact of mindfulness training on stress and associated brain plasticity has been shown in adults, whereas the impact of such training in the developing brain remains unknown. To address this open question, 40 middle-school children were randomized to either mindfulness or coding training (active control) interventions during the school day for eight weeks. Outcome measures were ratings of self-perceived stress and right amygdala activation while viewing fearful, happy, and neutral facial expressions during functional MRI. Prior to intervention, greater stress correlated with greater right amygdala activation in response to fearful versus neutral facial expressions across all children. After intervention, children who received mindfulness training reported lower stress associated with reduced right amygdala activation to fearful faces relative to children in the control condition. Amygdala responses to happy faces were unrelated to either initial stress or mindfulness reduction of stress. Moreover, mindfulness training led to relatively stronger functional connectivity between the right amygdala and ventromedial prefrontal cortex during the viewing of fearful facial expressions. Changes in perceived stress and neuroplasticity occurred in nonmeditative states, indicating that the benefits of mindfulness training generalized beyond the active meditative state. This study provides initial evidence that mindfulness training in children reduces stress and promotes functional brain changes and that such training can be integrated into the school curriculum for entire classes. This study also reveals first evidence that a neurocognitive mechanism for both stress and its reduction by mindfulness training is related specifically to reduced amygdala responses to negative stimuli. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Amígdala del Cerebelo/fisiología , Atención Plena/métodos , Estrés Psicológico/terapia , Adolescente , Encéfalo/fisiología , Mapeo Encefálico , Niño , Emociones/fisiología , Expresión Facial , Reconocimiento Facial/fisiología , Miedo/fisiología , Miedo/psicología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Corteza Prefrontal/fisiología
8.
Neuroimage ; 151: 117-127, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-26921712

RESUMEN

BACKGROUND: Meditation is increasingly showing beneficial effects for psychiatric disorders. However, learning to meditate is not straightforward as there are no easily discernible outward signs of performance and thus no direct feedback is possible. As meditation has been found to correlate with posterior cingulate cortex (PCC) activity, we tested whether source-space EEG neurofeedback from the PCC followed the subjective experience of effortless awareness (a major component of meditation), and whether participants could volitionally control the signal. METHODS: Sixteen novice meditators and sixteen experienced meditators participated in the study. Novice meditators were briefly trained to perform a basic meditation practice to induce the subjective experience of effortless awareness in a progressively more challenging neurofeedback test-battery. Experienced meditators performed a self-selected meditation practice to induce this state in the same test-battery. Neurofeedback was provided based on gamma-band (40-57Hz) PCC activity extracted using a beamformer algorithm. Associations between PCC activity and the subjective experience of effortless awareness were assessed by verbal probes. RESULTS: Both groups reported that decreased PCC activity corresponded with effortless awareness (P<0.0025 for each group), with high median confidence ratings (novices: 8 on a 0-10 Likert scale; experienced: 9). Both groups showed high moment-to-moment median correspondence ratings between PCC activity and subjective experience of effortless awareness (novices: 8, experienced: 9). Both groups were able to volitionally control the PCC signal in the direction associated with effortless awareness by practicing effortless awareness meditation (novices: median % of time=77.97, P=0.001; experienced: 89.83, P<0.0005). CONCLUSIONS: These findings support the feasibility of using EEG neurofeedback to link an objective measure of brain activity with the subjective experience of effortless awareness, and suggest potential utility of this paradigm as a tool for meditation training.


Asunto(s)
Concienciación/fisiología , Electroencefalografía , Giro del Cíngulo/fisiología , Meditación/métodos , Neurorretroalimentación , Femenino , Ritmo Gamma , Humanos , Masculino , Persona de Mediana Edad , Atención Plena , Volición
9.
Neuroimage ; 146: 157-170, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27836708

RESUMEN

This data descriptor describes a repository of openly shared data from an experiment to assess inter-individual differences in default mode network (DMN) activity. This repository includes cross-sectional functional magnetic resonance imaging (fMRI) data from the Multi Source Interference Task, to assess DMN deactivation, the Moral Dilemma Task, to assess DMN activation, a resting state fMRI scan, and a DMN neurofeedback paradigm, to assess DMN modulation, along with accompanying behavioral and cognitive measures. We report technical validation from n=125 participants of the final targeted sample of 180 participants. Each session includes acquisition of one whole-brain anatomical scan and whole-brain echo-planar imaging (EPI) scans, acquired during the aforementioned tasks and resting state. The data includes several self-report measures related to perseverative thinking, emotion regulation, and imaginative processes, along with a behavioral measure of rapid visual information processing. Technical validation of the data confirms that the tasks deactivate and activate the DMN as expected. Group level analysis of the neurofeedback data indicates that the participants are able to modulate their DMN with considerable inter-subject variability. Preliminary analysis of behavioral responses and specifically self-reported sleep indicate that as many as 73 participants may need to be excluded from an analysis depending on the hypothesis being tested. The present data are linked to the enhanced Nathan Kline Institute, Rockland Sample and builds on the comprehensive neuroimaging and deep phenotyping available therein. As limited information is presently available about individual differences in the capacity to directly modulate the default mode network, these data provide a unique opportunity to examine DMN modulation ability in relation to numerous phenotypic characteristics.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiopatología , Bases de Datos Factuales , Imagen por Resonancia Magnética , Trastornos Mentales/fisiopatología , Neurorretroalimentación , Adulto , Imagen Eco-Planar , Femenino , Humanos , Individualidad , Difusión de la Información , Almacenamiento y Recuperación de la Información , Masculino , Persona de Mediana Edad , Vías Nerviosas , Neuroimagen , Fenotipo , Adulto Joven
10.
Menopause ; 19(4): 426-32, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22240636

RESUMEN

OBJECTIVE: The aim of this study was to investigate the potential effects of pomegranate seed oil (PGS) on menopausal symptoms. METHODS: The prospective randomized, placebo-controlled, double-blinded trial was completed by 81 postmenopausal women, who received two daily doses of either 30 mg PGS containing 127 µg of steroidal phytoestrogens per dose or a placebo for 12 weeks. The participants reported their number of hot flashes and completed the Menopause Rating Scale II at baseline and at weeks 4, 8, 12, and 24. At baseline and after 12 weeks, hormonal status was determined. RESULTS: After 12 weeks of treatment, PGS reduced the number of hot flashes per day by 4.3 (38.7%), whereas placebo reduced it by 2.5 (25.6%). Both groups were significant compared with baseline, but the treated group was not significant compared with the placebo group (P = 0.17). After 24 weeks, the treated group showed a mean of 7.1 (interquartile range, 4.0) hot flashes per day compared with the placebo group with a mean of 8.8 (interquartile range, 5.0; P = 0.02). Although the overall sum score of the Menopause Rating Scale II parameters at week 12 decreased in the treated group from 16.0 to 9.0 at week 12 and in the placebo group from 18.0 to 14.5 (P = 0.08), the sum score of the vegetative somatic symptoms subgroup decreased strongly versus placebo (P < 0.03), attributable mainly to an improvement in sleeping disorders. PGS did not affect the hormone status, and no adverse effects were reported. CONCLUSIONS: In postmenopausal women, PGS does not significantly reduce hot flashes within a 12-week observation period, but further studies are needed to investigate the long-term effect.


Asunto(s)
Sofocos/tratamiento farmacológico , Lythraceae , Menopausia/efectos de los fármacos , Aceites de Plantas/administración & dosificación , Semillas , Adulto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Resultado del Tratamiento , Salud de la Mujer
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