The unusually active auditory system: Psychophysics and imaging of human echolocation
* Presenting author
For blind humans there is one perceptual strategy to assess far space, beyond the region of touch, namely to produce sounds and listen to how the environment alters the sounds on their way from the source to the receiver: Echolocation or biosonar is the hallmark of bats and toothed whales, but quite some time ago, it became clear that also humans can orient and navigate surprisingly well based on the auditory analysis of the echoes of self-generated sounds. Our work focuses on using virtual-space techniques to formally explore what humans can do with echolocation and what are the underlying perceptual and vocal-motor strategies that facilitate effective human echolocation. We will report on how human echolocation counteracts the precedence effect, i.e., our default auditory processes that explicitly suppress echoes, how humans assess the size of a room through echolocation, and what parts of the brain are involved in echolocation. Moreover, we report on how subject motion facilitates echo-acoustic orientation in virtual rooms and outline ways towards an echo-acoustic VR that would allow blind humans to train their orientation and navigation through echolocation in a save and controllable environment.