LPP seminar: Casimir Ludwig, School of Experimental Psychology, University of Bristol
Monday, February 20 2017, 11h
Salle de réunion du LPP, H432, 4ème étage, Centre Biomédical des Saints Pères 45 rue des Sts Pères, 75006 Paris
Gaze control in information foraging for perceptual decisions
Many perceptual judgements involve actively sampling visual information from the environment with gaze. We pick up visual information by fixating different locations in the scene and, typically, we put this information together in order to decide on a course of action (e.g. where to place your foot on a rocky path). Most models and studies of perceptual decision making typically involve just a single source of information that has to be mapped onto a small number of discrete decision categories. I will present work on the control of eye movements in decision problems that involve actively gathering and combining visual information from several locations.
I will focus on two key questions: (i) How is time allocated to different sources of information that may vary in the quality of evidence they provide? (ii) What decision variable is being computed to govern the active sampling strategy? Our work shows that time is allocated adaptively in that more noisy information sources are sampled for longer, particularly when prior knowledge about the information quality of different sources is available. In addition, participants are able to track some measure of their own uncertainty around the task relevant variable (visual motion in this case), which may be used to govern their sampling strategy online.
Invited by the Vision team