Influence of sucrose ingestion on brainstem and hypothalamic intrinsic oscillations in lean and obese women.

Background & Aims: The study of intrinsic fluctuations in the blood oxygen level-dependent signal of functional magnetic resonance imaging can provide insight into the effect of physiologic states on brain processes. In an effort to better understand the brain-gut communication induced by the absorption and metabolism of nutrients in healthy lean and obese individuals, we investigated whether ingestion of nutritive and non-nutritive sweetened beverages differentially engages the hypothalamus and brainstem vagal pathways in lean and obese women.

Methods: In a 2-day, double-blind crossover study, 11 lean and 11 obese healthy women underwent functional magnetic resonance imaging scans after ingestion of 2 beverages of different sucrose content, but identical sweetness.

Impact of Mindfulness-Based Stress Reduction training on intrinsic brain connectivity.

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.

Effect of abuse history on pain reports and brain responses to aversive visceral stimulation: an FMRI study.

Background & Aims: Abuse history is common in irritable bowel syndrome (IBS) and is associated with greater pain reporting, psychologic distress, and poorer health outcome. These effects may be mediated by enhanced responses to aversive visceral stimuli. We investigated the effects of IBS and abuse history on pain reporting and brain activation in response to rectal distentions.

The neural correlates of placebo effects: a disruption account.

The neurocognitive pathways by which placebo effects operate are poorly understood. Positron emission tomography (PET) imaging was used to assess the brain response of patients with chronic abdominal pain (irritable bowel syndrome; IBS) to induced intestinal discomfort both before and after a 3-week placebo regimen. A daily symptom diary was used to measure symptom improvement.