Neuroimaging studies show that the functional connectivity of the brain changes with age. Resting state functional connectivity (rsFC) in the brain appears to decrease with aging in key networks associated with higher order thinking and effective emotional regulation. Interventions that potentially preserversFC in the brain include 1) physical activity and 2) contemplative practice commonly...
Human neuroimaging studies report that psychedelics induce serotonin-2A receptor-dependent changes in functional brain reorganization, presumably reflecting neuromodulation. However, these studies often overlook the potent vasoactive effects of serotonin. Here we identified psilocybin-induced alterations in hemodynamic response functions during human functional magnetic resonance imaging,...
Psilocybin (PSIL) is a psychedelic drug and a promising experimental therapeutic for many psychiatric conditions. Precision functional mapping (PFM) combines densely repeated resting state fMRI sampling and individual-specific network mapping to improve signal-to-noise ratio (SNR) and effect size in brain imaging research. We present a randomized cross-over study in which PFM was used to...
A single dose of psilocybin, a psychedelic that acutely causes distortions of space-time perception and ego dissolution, produces rapid and persistent therapeutic effects in human clinical trials1-4. In animal models, psilocybin induces neuroplasticity in cortex and hippocampus5-8. It remains unclear how human brain network changes relate to subjective and lasting effects of psychedelics. Here...
JAMADecember 13, 2022Eric J Lenze, Michelle Voegtle, J Philip Miller et al.
Episodic memory and executive function are essential aspects of cognitive functioning that decline with aging. This decline may be ameliorable with lifestyle interventions. To determine whether mindfulness-based stress reduction (MBSR), exercise, or a combination of both improve cognitive function in older adults. This 2 × 2 factorial randomized clinical trial was conducted at 2 US sites...
Ketamine produces a rapid antidepressant response in over 50% of adults with treatment-resistant depression. A long infusion of ketamine may provide durable remission of depressive symptoms, but the safety, efficacy, and neurobiological correlates are unknown. In this open-label, proof-of-principle study, adults with treatment-resistant depression (N = 23) underwent a 96-h infusion of...
Age-related cognitive decline is a pervasive problem in our aging population. To date, no pharmacological treatments to halt or reverse cognitive decline are available. Behavioral interventions, such as physical exercise and Mindfulness-Based Stress Reduction, may reduce or reverse cognitive decline, but rigorously designed randomized controlled trials are needed to test the efficacy of such...
Functional MRI (fMRI) studies have shown that low-frequency (<0.1 Hz) spontaneous fluctuations of the blood oxygenation level dependent (BOLD) signal during restful wakefulness are coherent within distributed large-scale cortical and subcortical networks (resting state networks, RSNs). The neuronal mechanisms underlying RSNs remain poorly understood. Here, we describe magnetoencephalographic...
BackgroundImportant functional connections within the default mode network (DMN) are disrupted in Alzheimer's disease (AD), likely from amyloid-beta (Abeta) plaque-associated neuronal toxicity. Here, we sought to determine if pathological effects of Abeta amyloid plaques could be seen, even in the absence of a task, by examining functional connectivity in cognitively normal participants with...
A baseline or control state is fundamental to the understanding of most complex systems. Defining a baseline state in the human brain, arguably our most complex system, poses a particular challenge. Many suspect that left unconstrained, its activity will vary unpredictably. Despite this prediction we identify a baseline state of the normal adult human brain in terms of the brain oxygen...