This PhD project will investigate the brain circuits that bridge sensory processing, motor planning and action execution, focusing on interactions between the motor cortex, thalamus and superior colliculus (SC). Of particular interest are genetically defined Pitx2 neurons in the SC, which receive cortical motor signals, communicate with thalamic and downstream motor regions, and are organised into spatial modules capable of generating specific orienting movements. Their unique connectivity suggests that they may provide a crucial link between where an animal intends to go and the actions required to get there.
To investigate this, we have developed a freely moving spatial GO-NOGO task in which mice use sensory cues to navigate towards goals in a three-dimensional environment. Unlike traditional head-fixed tasks involving simple left/right choices, this approach allows us to study decision-making and motor planning during naturalistic, whole-body behaviour.
The student will combine this behavioural paradigm with state-of-the-art approaches including high density neural recordings and multiphoton imaging, optogenetic manipulation, viral circuit tracing and quantitative behavioural analysis. By following and manipulating neural activity as animals progress from sensing a cue to planning and executing an action, the project aims to uncover fundamental principles by which the brain transforms perception and intention into purposeful movement.
Other PhD projects may also be available. Please visit the project page on our website to explore the lab’s broader research programme.
Funding Notes
References
Gonzalez-Rueda, A., Jensen, K., Noormandipour, M., de Malmazet, D., Wilson, J., Ciabatti, E., Kim, J., Williams, E., Poort, J., Hennequin, G., and Tripodi, M. (2024). Kinetic features dictate sensorimotor alignment in the superior colliculus. Nature 631, 378-385. 10.1038/s41586-024-07619-2.
Lee, H., Ciabatti, E., Gonzalez-Rueda, A., Williams, E., Nugent, F., Mookerjee, S., Morgese, F., and Tripodi, M. (2023). Combining long-term circuit mapping and network transcriptomics with SiR-N2c. Nat Methods, 580-589. 10.1038/s41592-023-01787-1.
Ciabatti, E., Gonzalez-Rueda, A., Mariotti, L., Morgese, F., and Tripodi, M. (2017). Life-Long Genetic and Functional Access to Neural Circuits Using Self-Inactivating Rabies Virus. Cell 170, 382-392 e314. 10.1016/j.cell.2017.06.014
Masullo, L., Mariotti, L., Alexandre, N., Freire-Pritchett, P., Boulanger, J., and Tripodi, M. (2019). Genetically Defined Functional Modules for Spatial Orienting in the Mouse Superior Colliculus. Curr Biol. 29, 2892-2904 e2898. 10.1016/j.cub.2019.07.083.
Wilson, J.J., Alexandre, N., Trentin, C., and Tripodi, M. (2018). Three-Dimensional Representation of Motor Space in the Mouse Superior Colliculus. Curr Biol. 10.1016/j.cub.2018.04.021.
