Learning how movements displace an animal in space is vital for survival. The relationship between locomotor commands in the brain and their consequences are subject to frequent changes both in bodily properties such as during injury or muscle fatigue, and environmental properties like terrain firmness.
As animals move through space, they create optic flow (OF) fields and have sophisticated neural systems to detect them. It is thought that to estimate the casual relationship between movements and their consequences all animals, including humans, have internal movement representations and compare them to outcome. How these movement representations are updated to sensory stimuli, such as optic flow, is not understood for any animal species. Understanding how animals adapt their movements to sensory feedback is essential for any complete theory of how behavior is generated.
The fly’s visual system has neurons (HS cells) that respond both to optic flow and to the movements that a fly does when walking. Also, serotonergic neurons located in the posterior medial protocerebral (PMPV) cluster were shown to reduce walking in flies.
The aim of this project is to test the hypothesis that the visual-motor signals generated by HS cells are used to calibrate movements to visual flow and that this calibration is performed by the action of serotonergic neurons in the PMPV cluster.
Linking HS neural activity to motor learning would provide an explanation why these self-movement representations exist in the brain and inspire new motor learning theories, that could be of great use in robotics. Also, serotonin is the most important pharmacological target for anxiety and depression. Therefore, any understanding on its function may help to design more effective therapies for these diseases. Furthermore, implicating serotonin in motor learning may uncover new uses for serotonin-based drugs in people with learning disabilities. Finally, this project involves creating a computational framework to track the movements that an animal does, that could be adapted to other animal species and to tackle other scientific questions.
