The way that external stimuli are encoded in brain activity is increasingly well understood. In contrast, we sorely lack a mechanistic understanding of interoception—the processes by which the brain receives, attends to, and acts upon visceral signals arising from inside the body (e.g., heartbeat, stomach stretch, pain). This is surprising given the urgent clinical mandate for understanding body-brain communication and its disruptions (e.g., in eating disorders, anxiety disorders, addiction, autism, pain, and cardiovascular, gastrointestinal and respiratory disorders). Our research aims to establish a cognitive neuroscience of interoception at cellular resolution. Specifically, we are defining the cellular and circuit mechanisms by which predictions, sensations, awareness, attention, and memory of body signals help restore and maintain homeostasis. Our recent findings suggest that insular cortex integrates bodily signals of energy/water deficits with cues conveying food or water availability to correct the deficits. By imaging hundreds of neurons in insular cortex of behaving mice, we identified distinct patterns of active neurons during states of energy deficit or dehydration. During detection and consumption of small amounts of food or water, insular cortex activity transiently shifts to a pattern associated with a future satiety state. We argue that the cerebral cortex and its connections with the brainstem, midbrain, and hypothalamus are central to active cognitive control of homeostasis.
As an Innovation Fund investigator, Andermann is collaborating with the lab of Viviana Gradinaru, Ph.D., to investigate how the brain’s insular cortex perceives bodily signals from internal organs. Sensation and awareness of one’s condition (e.g., pain, itch, or heartbeat) are important for the brain to coordinate the right responses to ensure well-being and survival. Combining their expertise in neuroscience, imaging, and molecular methodologies, the team aims to map the responses of the insular cortex to signals (e.g., those that vary with hunger versus fullness) from various parts of the gastrointestinal tract in mice. This work could aid in better understanding how this sensory system relays information from the body to the brain, and how the insular cortex helps to promote survival.