First published July 1 2016
Listening to a world transformed: Perception in an inverted acoustic field.
Fernando Bermejo, Ezequiel Di Paolo, and Claudia Arias
Research into perceptual and behavioural adaptations to radical disruptions of the agent-environment coupling has long been an interest of dynamical and embodied agent-based modeling. While existing artificial life models draw inspiration from Kohlers experiments on visual disruptions, their sensorimotor instantiation is rather minimal, typically involving two point photoreceptors and a point source of light and so arguably a better match for sensorimotor engagements in the auditory modality. However, studies into human adaptation to inversion of the auditory space are scarce. Here we report on the development and a series of preliminary studies regarding the role of activity and passivity in human adaptation to wearing a left-right auditory inversion device, or pseudophone, in different sound localization tasks. The de-stabilization of sensorimotor contingencies produced by this device allows us to analyze different kinds of sensory activity involved in the auditory system in non-obvious ways. Participants report that their movements induce surprising perceptual changes as if aspects of the auditory scene expected to remain static moved without correspondence to the action. Previous evolutionary robotics work on minimal categorization under ambiguous sensory fields suggests that training with the pseudophone under random presentation of the auditory inversion should result in the development of a single sensorimotor strategy able to actively disambiguate the different modes.