RESUMO
Resting-state functional magnetic resonance imaging has been used to investigate intrinsic brain connectivity in healthy subjects and patients with chronic pain. Sex-related differences in the frequency power distribution within the human insula (INS), a brain region involved in the integration of interoceptive, affective, and cognitive influences, have been reported. Here we aimed to test sex and disease-related alterations in the intrinsic functional connectivity of the dorsal anterior INS. The anterior INS is engaged during goal-directed tasks and modulates the default mode and executive control networks. By comparing functional connectivity of the dorsal anterior INS in age-matched female and male healthy subjects and patients with irritable bowel syndrome (IBS), a common chronic abdominal pain condition, we show evidence for sex and disease-related alterations in the functional connectivity of this region: (1) male patients compared with female patients had increased positive connectivity of the dorsal anterior INS bilaterally with the medial prefrontal cortex (PFC) and dorsal posterior INS; (2) female patients compared with male patients had greater negative connectivity of the left dorsal anterior INS with the left precuneus; (3) disease-related differences in the connectivity between the bilateral dorsal anterior INS and the dorsal medial PFC were observed in female subjects; and (4) clinical characteristics were significantly correlated to the insular connectivity with the dorsal medial PFC in male IBS subjects and with the precuneus in female IBS subjects. These findings are consistent with the INS playing an important role in modulating the intrinsic functional connectivity of major networks in the resting brain and show that this role is influenced by sex and diagnosis.
Assuntos
Dor Abdominal/fisiopatologia , Córtex Cerebral/fisiopatologia , Dor Crônica/fisiopatologia , Rede Nervosa/fisiopatologia , Caracteres Sexuais , Dor Abdominal/diagnóstico , Adulto , Dor Crônica/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto JovemRESUMO
The beneficial effects of mindful awareness and mindfulness meditation training on physical and psychological health are thought to be mediated in part through changes in underlying brain processes. Functional connectivity MRI (fcMRI) allows identification of functional networks in the brain. It has been used to examine state-dependent activity and is well suited for studying states such as meditation. We applied fcMRI to determine if Mindfulness-Based Stress Reduction (MBSR) training is effective in altering intrinsic connectivity networks (ICNs). Healthy women were randomly assigned to participate in an 8-week Mindfulness-Based Stress Reduction (MBSR) training course or an 8-week waiting period. After 8 weeks, fMRI data (1.5T) was acquired while subjects rested with eyes closed, with the instruction to pay attention to the sounds of the scanner environment. Group independent component analysis was performed to investigate training-related changes in functional connectivity. Significant MBSR-related differences in functional connectivity were found mainly in auditory/salience and medial visual networks. Relative to findings in the control group, MBSR subjects showed (1) increased functional connectivity within auditory and visual networks, (2) increased functional connectivity between auditory cortex and areas associated with attentional and self-referential processes, (3) stronger anticorrelation between auditory and visual cortex, and (4) stronger anticorrelation between visual cortex and areas associated with attentional and self-referential processes. These findings suggest that 8 weeks of mindfulness meditation training alters intrinsic functional connectivity in ways that may reflect a more consistent attentional focus, enhanced sensory processing, and reflective awareness of sensory experience.
Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Meditação/psicologia , Vias Neurais/fisiologia , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estresse Psicológico/prevenção & controle , Estresse Psicológico/psicologia , Adulto JovemRESUMO
BACKGROUND: Irritable bowel syndrome (IBS) is a common and often debilitating chronic gastrointestinal disorder characterized by abdominal pain and altered bowel habits. Pharmacological treatments are often ineffective, leading to the development of a variety of behavioral interventions. Mindfulness-based stress reduction (MBSR) is one such program that has shown efficacy in reducing gastrointestinal (GI) symptoms and improving quality of life (QOL). This single-arm intervention study examines the association of clinical outcomes with changes in specific aspects of mindfulness. METHODS: Adults with IBS (53 women, 15 men) participated in an 8-week MBSR class. Primary outcomes of GI symptom severity, quality of life, and GI-specific anxiety, as well as specific aspects of mindfulness using the Five Factor Mindfulness Questionnaire (FFMQ), were assessed at baseline, post-treatment, and 6-month follow-up. KEY RESULTS: Gastrointestinal symptom responder rate was 71%, and there was a significant pre-post treatment change for three of the five FFMQ scales. Regression analysis indicated that change in the Act with Awareness (P = .02) facet of mindfulness was the strongest predictor of GI symptom and QOL improvement. CONCLUSIONS & INFERENCES: Mindfulness-based stress reduction training was associated with robust improvements in GI symptoms and associated problems in participants with IBS. Although significant increases in 3 of the 5 measured facets of mindfulness were found, regression analyses suggest that increases in the ability to retain present moment focus and act with awareness may be particularly important for improving outcomes in individuals with IBS. These results may inform the refinement of mindfulness-based protocols specifically for treatment of IBS.
Assuntos
Terapia Comportamental/métodos , Síndrome do Intestino Irritável/terapia , Atenção Plena/métodos , Qualidade de Vida/psicologia , Estresse Psicológico/terapia , Adulto , Feminino , Humanos , Síndrome do Intestino Irritável/diagnóstico , Síndrome do Intestino Irritável/psicologia , Masculino , Índice de Gravidade de Doença , Estresse Psicológico/psicologiaRESUMO
U.S. university students hold generally medicalized views on childbirth, which contrast with evidence indicating that low-intervention birth is safest for most. Therefore, intentional efforts are needed to educate childbearing populations on perinatal care evidence. Toward that aim, this study involved teaching university students in an introductory class (N = 50) about evidence-based perinatal care. Students completed a "future birth plan" and an essay on how their learning affected care preferences. Analyses revealed that students selected evidence-based care components up to 100 times more frequently than what the national data indicate they are used. Students based care selections on evidence, costs, and personal views. Their interest in physiologic birth has important implications for advancing education on perinatal care, practice, and policy.
RESUMO
Placebo analgesia is measured by self-report, yet current, expected, and recalled efficacy may be differentially related to brain function. Here we used a human thermal pain model to compare self-reports of expected, concurrent, and recalled efficacy of a topical placebo analgesic, and tested associations of the three measures of efficacy with changes in dopamine D2/D3 receptor availability in brain using [(18)F]fallypride with positron emission tomography (PET). Participants (15 healthy women) were assessed on three test days. The first test day included a laboratory visit, during which the temperature needed to evoke consistent pain was determined, placebo analgesia was induced via verbal and experience-based expectation, and the placebo response was measured. On two subsequent test days, PET scans were performed in Control and Placebo conditions, respectively, in counterbalanced order. During Visit 1, concurrent and recalled placebo efficacy were unrelated; during the Placebo PET visit, expected and recalled efficacy were highly correlated (ρ = 0.68, p = 0.005), but concurrent efficacy was unrelated to expected or recalled efficacy. Region of interest analysis revealed dopamine D2/D3 receptor availability was lower in left ventrolateral prefrontal cortex in the Placebo condition (p < 0.001, uncorrected), and greater change in this measure was associated with higher levels of recalled analgesic efficacy (ρ = 0.58, p = 0.02). These preliminary findings underscore the need to consider how self-reported symptom improvement is assessed in clinical trials of analgesics and suggest that dopaminergic activity in the ventrolateral prefrontal cortex may promote recalled efficacy of placebo.
Assuntos
Analgesia/psicologia , Encéfalo/fisiologia , Dopamina/metabolismo , Percepção da Dor/fisiologia , Efeito Placebo , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/metabolismo , Adulto , Benzamidas/metabolismo , Encéfalo/metabolismo , Feminino , Fluordesoxiglucose F18 , Temperatura Alta , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Autorrelato , Adulto JovemRESUMO
Regional cortical thickness alterations have been reported in many chronic inflammatory and painful conditions, including inflammatory bowel diseases (IBD) and irritable bowel syndrome (IBS), even though the mechanisms underlying such neuroplastic changes remain poorly understood. In order to better understand the mechanisms contributing to grey matter changes, the current study sought to identify the differences in regional alterations in cortical thickness between healthy controls and two chronic visceral pain syndromes, with and without chronic gut inflammation. 41 healthy controls, 11 IBS subjects with diarrhea, and 16 subjects with ulcerative colitis (UC) underwent high-resolution T1-weighted magnetization-prepared rapid acquisition gradient echo scans. Structural image preprocessing and cortical thickness analysis within the region of interests were performed by using the Laboratory of Neuroimaging Pipeline. Group differences were determined using the general linear model and linear contrast analysis. The two disease groups differed significantly in several cortical regions. UC subjects showed greater cortical thickness in anterior cingulate cortical subregions, and in primary somatosensory cortex compared with both IBS and healthy subjects. Compared with healthy subjects, UC subjects showed lower cortical thickness in orbitofrontal cortex and in mid and posterior insula, while IBS subjects showed lower cortical thickness in the anterior insula. Large effects of correlations between symptom duration and thickness in the orbitofrontal cortex and postcentral gyrus were only observed in UC subjects. The findings suggest that the mechanisms underlying the observed gray matter changes in UC subjects represent a consequence of peripheral inflammation, while in IBS subjects central mechanisms may play a primary role.