Glia and circuit regulation / Astrocytes and the computation of neural circuits
Neural circuits are often described from the perspective of neurons. Neurons generate electrical signals, form networks, store information, and change with experience. Yet this framework only captures part of the complexity. Every neuron operates within a dense cellular environment that is populated by astrocytes, glial cells that closely associate with synapses, monitor neural activity, and influence synaptic plasticity.
For decades, astrocytes were viewed primarily as support cells, the “glue” that keeps the brain together. They provide metabolic resources and maintain the conditions that allow neurons to function. These roles are indispensable, but they are only part of what astrocytes do.
Astrocytes are active participants in neural circuit function.
They detect neurotransmitter release, respond to neural activity, regulate synaptic signaling, and communicate with surrounding circuits. Astrocytes interface with thousands of synapses, which uniquely situates them in a position to influence information flow through neural circuits and impact how those circuits adapt to experience.
Our lab seeks to understand: how do astrocytes contribute to neural computation and plasticity?
One major focus on or work is the brain’s reward circuitry, particularly the nucleus accumbens, a region that integrates information and guides motivated behaviors. Our studies have shown that astrocytes within this circuit influence how animals respond to rewarding experiences. When astrocyte function is selectively altered, an animal’s valuation of reward is completely changed: animals work harder to obtain rewards and consume more of both natural and drug rewards. These findings suggest that astrocytes are not simply supporting neural circuitry. They are helping determine how the circuit functions.
This raises a broader set of questions: What information do astrocytes extract from neural activity? How do they integrate signals across networks and actively shape circuit output? How does astrocyte activity influence nearby synapses and neurons? And how do these cellular interactions ultimately affect the choices an animal makes?
Answering these questions requires studying neurons and astrocytes as components of a single integrated system. We combine viral cell type-specific manipulations, optogenetics, chemogenetics, patch clamp electrophysiology, and ex vivo and in vivo calcium signaling with machine learning-driven behavioral analysis to follow the consequences of astrocyte activity across multiple levels of organization.
This approach allows us to move beyond asking whether astrocytes matter and instead investigate how they matter.
By uncovering how astrocytes regulate neuronal activity, synaptic plasticity, and circuit dynamics, we aim to develop a more complete understanding of how the brain processes information and generates behavior.