Completed notes of the course

Pagina 1

Part 1- Introduction to Motor Control and Learning Motor control and learning deal with how the brain plans, executes, and adapts movements to achieve desired goals. It involves understanding how neural, muscular, and sensory systems interact to produce coordinated and flexible motion. The main issues associated with movement are delays and noise, which are present both in the sensory data and in the motor commands (referred to as resolution limit and control limit, respectively). Usually, we work under the hypothesis of time invariance or stationarity. However, when we consider actual movement, it is highly time-varying: prediction and learning are therefore essential features of our motor system. Is the system linear? No, our motor system is strongly non-linear . A clear example is saturation, such as in the range of motion or in the neural signals required to perform counter-gravity movements. Considering that the human body has about 600 muscles, this implies at least 600 potential outputs, leading to around 10² ⁰ possible output combinations. In this context, synergy plays a key role: the nervous system can efficiently coordinate groups of muscles to produce precise and adaptive movements. Sensorimotor integration Sensorimotor integration refers to the continuous process by which sensory information is combined with motor commands to guide and adjust movement. It allows the brain to update motor plans in real time based on feedback from the body and the environment. In order to study this problem, we need to split it into two main phases: kinematics and dynamics transformation. In fact, movements occur through a transformation cascade . Movements can be both voluntary or involuntary (reflexes); here we’ll focus on the first category. There can be many different…