Our research
Cognitive models are built from many different types of learnt associations that are stored in different neuronal populations throughout the brain. Which type of memory that is encoded or recalled is dependent on a complex interplay of factors driven by interactions at the circuit level. Disruptions in this process can contribute to a broad range of psychological disorders including schizophrenia, addiction, anxiety, and post-traumatic stress disorder (PTSD).
We study the nature of these cognitive deficits and how a disruption of particular neural circuits may produce them. Our hope is that if we can understand how learning is disrupted in these disorders, it will provide the impetus to develop novel therapeutic compounds targeting the neural circuits we know are important for these aspects of learning, to reduce symptoms and improve quality of life in patients.
Our current projects
The lab is interested in how different neuronal circuits integrate information to regulate the development of cognitive models. In particular,
- How is the teaching signal from dopamine neurons utilized in different neural circuits to regulate different types of learnt associations?
- How does the lateral hypothalamus contribute to learning?
- How do the orbitofrontal and prelimbic cortices contribute to state-dependent learning via control over striatal regions?
- How might a disruption in building these cognitive models contribute to schizophrenia and addiction?
We primarily use complex behavioural tasks designed within Med Associates systems. We combine these sophisticated behavioural designs afforded by these systems with a modern suite of neuroscience tools including:
- in-vivo imaging of neuronal activity using fiber photometry of genetically-encoded calcium and dopamine sensors,
- manipulation of specific neuronal populations using optogenetics and chemogenetics in transgenic rodent strains, and
- a variety of techniques to facilitate circuit tracing through light and fluorescence microscopy, and immunohistochemistry.
This affords recording and manipulation of neural circuits during behavioral tasks with a temporal precision that allows us to ask very specific questions about how the brain learns.
See our recent publications on Dr Melissa Sharpe's academic profile.
Image on this page courtesy of Thijs Dhollander