Gut Influences on Brain and Mind

Objective

A “gut feeling” is an intuition arising without conscious reasoning. This idiom reflects a profound biological truth: the gut is directly connected to subcortical systems that regulate arousal, mood, and behavior. However, brain-body theories often overlook these connections and their influence on arousal, a key mechanism through which the gut affects cognition. Moreover, we lack a detailed understanding of how different time scales of gut activity -from rapid contractions (seconds to minutes) to slower hormonal fluctuations (minutes to hours)- interact with brain dynamics, mood, and cognition. Critically, this gap also extends to mental health, where gut signals are increasingly recognized for their crucial role, yet a comprehensive mechanistic framework linking specific symptoms to altered brain-gut interactions remains absent. GUT-FEEL will address these challenges by systematically investigating gut-brain interactions across the vigilance, affective, and physiological dimensions of arousal, using pharmacological manipulations of the gut and brain. By combining non-invasive measurements of stomach activity with a dense, hourly sampling of gut hormones, I will probe how fast and slow gut signals interact with brain activity, captured simultaneously through electroencephalography and functional magnetic resonance imaging. This novel approach will allow me to untangle the complex web of interactions between the gut and the brain, both in healthy individuals and in those with depression. By positioning the gut as a critical modulator of brain function, GUT-FEEL will reshape our understanding of the intricate links between the brain, body, and mind. This groundbreaking approach will push the boundaries of cognitive neuroscience and pave the way for gut-focused therapeutic interventions, revolutionizing how we understand and treat mental health conditions such as depression. In doing so, GUT-FEEL is set to redefine the future of brain-body research.