Effects of external stimulation on psychedelic state neurodynamics

Recent findings have shown that psychedelics reliably enhance brain entropy (understood as neural signal diversity), and this effect has been associated with both acute and long-term psychological outcomes, such as personality changes. These findings are particularly intriguing, given that a decrease of brain entropy is a robust indicator of loss of consciousness (e.g., from wakefulness to sleep). However, little is known about how context impacts the entropy-enhancing effect of psychedelics, which carries important implications for how it can be exploited in, for example, psychedelic psychotherapy. This article investigates how brain entropy is modulated by stimulus manipulation during a psychedelic experience by studying participants under the effects of lysergic acid diethylamide (LSD) or placebo, either with gross state changes (eyes closed vs open) or different stimuli (no stimulus vs music vs video). Results show that while brain entropy increases with LSD under all of the experimental conditions, it exhibits the largest changes when subjects have their eyes closed. Furthermore, brain entropy changes are consistently associated with subjective ratings of the psychedelic experience, but this relationship is disrupted when participants are viewing a video─potentially due to a “competition” between external stimuli and endogenous LSD-induced imagery. Taken together, our findings provide strong quantitative evidence of the role of context in modulating neural dynamics during a psychedelic experience, underlining the importance of performing psychedelic psychotherapy in a suitable environment.</p

Additional file 1 of An open-label pilot trial assessing tolerability and feasibility of LSD microdosing in patients with major depressive disorder (LSDDEP1)

Additional file 1. Participant information sheet and informed consent form

NATIONAL STATEMENT OF SCIENCE INVESTMENT DRAFT: Response from Rutherford Discovery Fellowship recipients (2010-2013)

<p>This is a joint response written and co-signed by 97.5% of New Zealand’s Rutherford Discovery Fellows. We are a group of internationally recognised early- to mid-career researchers who have been selected for our innovative approaches to research across the sciences and the humanities. We work in diverse fields, spanning physical, engineering, information and communications technology, medical, molecular and environmental research through to social sciences, law and the humanities. We are based across a wide cross-section of New Zealand’s Universities and Crown Research Institutes (CRIs), and are engaged in basic, applied and near-to-market research. All of us have directly benefitted from the investments and changes that the Government has been making to the Science sector. As a result of the Rutherford Discovery Fellowship, we have chosen to return to, or to stay in, New Zealand.</p> <p> </p