Neuronal circuits for sensory-body state integration

Thermal homeostasis is essential to survival.

But how our brain processes thermosensory information and triggers behaviors that help maintain our physiological, body state remains a mystery.

The neural circuits responsible for perception of sensory stimulation and those for regulation of body state have been studied independently, yet body state has a profound impact on sensory perception.

What is more, animals constantly adapt their behavior to maintain homeostasis with moment-by-moment sensing of the environment.

Current models suggest that the insular cortex plays a key role in integrating internal information about body state with external sensory information about the environment to generate signals that represent the difference between internal and external inputs. Such, ‘sensory-state difference’ signals allow us to navigate and adapt to a dynamic environment.

To test this model, our aim is to leverage distinct features of the thermal system and examine species with and without the ability to thermoregulate.

My team has recently located the primary cortical representation of temperature (a ‘thermal cortex’) in a posterior region of the insular cortex.

We will examine its activity as we monitor and manipulate the internal, core body temperature and external thermal input during robust and sensitive thermal behavior. We will compare human and mouse, which are warm-blooded, to naked mole-rats, which are nearly cold-blooded.

To identify the cellular mechanisms of sensory-state integration, we will use a combination of cutting-edge techniques including neural recordings, anatomical tracing and activity manipulations during a thermal perceptual task and thermoregulatory behavior.

Our holistic and comparative approach will provide insight into a fundamental question regarding cortical function and may help tackle disorders of body state associated with insular cortex dysfunction.