Project Summary How does the brain support a repertoire of complex, natural movements? Motor systems neuroscience stud- ies how neural dynamics in the motor system perform motor computations ranging from basic motor planning and execution to more complex ones such as motor error correction or visuomotor adaptation that allow us to reach our goals in a rich, changing world around us. To see how neural dynamics relate to these various mo- tor computations, studies traditionally employ a constrained experimental environment where restrained subjects perform virtual tasks through a computer screen and produce isolated arm reaches. This creates a generaliz- ability question: how do neural dynamics studied in the lab relate to those of performing movements in the real world? Underlying this question, there lies a more basic knowledge gap on how neural dynamics generalize for performing the same computation but in different tasks or environments, such as in freely-moving environments. This work aims to understand what is truly fundamental about motor cortical activity patterns for performing a motor computation, regardless of task or environmental context. Aim 1 will obtain a grounded understanding of how neural dynamics generalize for performing the same motor computation in different virtual tasks within the traditionally constrained environment. Aim 2 then tackles the question of how neural dynamics generalize for performing the same motor computation in a virtual task within the constrained environment to an analogous naturalistic task within the freely-moving environment. This work leverages a freely-moving experimental platform that acquires rich, synchronized behavioral data and neural data, combined with modeling of neural dynamics to understand how neurons coordinate similarly when performing similar computations in different tasks and en- vironments. Understanding how neural dynamics generalize from supporting artificially constrained behavior to freely-moving, naturalistic behavior will be a key achievement in neuroscience with applications towards under- standing how cortical control of natural motor functions go awry in people with stroke or brain injury and improving assistive neurotechnologies, such as neural prosthetics, for those with motor disabilities. This work provides the ideal opportunity to grow a diverse set of scientific, technical, and quantitative skills for career advancement as an independent scientist, under the guidance of Dr. Nuyujukian who has multi-disciplinary expertise at the intersection of neuroscience, medicine, and engineering. With the support from this fellowship, combined with unparalleled access to cutting-edge techniques and well-furnished facilities with a thriving scientific community at Stanford, this project is poised to succeed and make an impact in basic science and medicine.