Seminar Details
2020-05-12 (14:00) : Prediction and uncertainty in the control of visual tracking
At MS Teams
Organized by Mathematical Engineering
Speaker :
Lefèvre, Philippe
Abstract :
Vision plays a key role in behaviour. In humans, visual acuity is non-homogeneous across the visual field and is characterized by a foveal zone of very high resolution. Therefore, for human observers, the quality of visual inputs is heavily influenced by their ability to detect and fixate parts of the visual scene that are of particular interest. When everything is stationary if the environment, this is performed with saccades that are fast orienting eye movements allowing to scan the visual scene. However, in a dynamic environments, objects can move with respect to the observer, requiring to track moving objects with smooth pursuit eye movements.
Saccades and smooth pursuit eye movements are two different modes of oculomotor control. However, behavioural and neurophysiological data demonstrated that both types of eye movements work in synergy for visual tracking. This suggests that saccades and pursuit are two outcomes of a single sensorimotor process that aims at orienting the visual axis. More recently, it has been hypothesized that oculomotor behaviors integrate sensory (visual) and prior information to overcome sensory-motor delays and noise. After much debate about this process, reliability-based integration has recently been proposed and several models of smooth pursuit now include recurrent Bayesian integration or Kalman filtering.
In this talk, I will present some recent experimental and modeling work demonstrating the key role played by prediction and uncertainty in the synergy between saccades and smooth pursuit in the control of visual tracking.