Uncovering the underlying sophistication of human perception

27 Jul 2016

Uncovering the underlying sophistication of human perception

Uncovering the underlying sophistication of human perception
Dr Neeraj Kumar, Early Career Fellow and Dr Pratik K. Mutha
IIT Gandhinagar

How does a football player estimate where a ball kicked by him is going? One source of information for generating such an estimate is feedback about the ball’s motion provided by the player’s visual system. The player may also predict the trajectory that the ball is going to take based on his kicking action. We show in our recently published study in the Journal of Neurophysiology that such predictions about the sensory effects of actions can be a rich source of information, which, when combined with actual sensory feedback yields better perception of the world around us. In case of the football player, this implies that his/her judgment about the ball’s trajectory is enhanced by combining their predictions with information provided by their visual system. In our study, we blended a motor learning paradigm that imposes new sensory predictions with a dynamic visual search task to first show that perceptual judgments are poorer when they are based on sensory feedback that is misaligned with those predictions. We then show, perhaps for the first time, that perception is strongly influenced by the most stable sensory predictions available. We induced instability in the motor-learning induced predictions, and observed that people transitioned to using other stable predictions available for their perceptual judgments rather than relying on visual feedback alone as is conventionally thought. Finally, we show that when sensory predictions are not modified at all, these judgments are sharper when subjects combine their natural sensory predictions with actual sensory information. Collectively, these new and exciting findings uncover the tremendous operational flexibility and sophistication within the human perceptual system, and have substantial implications for theoretical and computational models of perception.

Adaptive reliance on the most stable sensory predictions enhances perceptual feature extraction of moving stimuli.
Neeraj Kumar, Pratik K. Mutha. Journal of Neurophysiology

 Image credit : Spike Walker, Wellcome Images  Cerebellum - the region of the brain involved in sensory perception Light microscopy