People can learn to distinguish rotating objects by the way they echo sounds

Sensing system. (A) denotes the configuration of the sensing system for target geometry identification. Once the participants tap Android devices A and B, the synthetic echolocation signal is emitted from the loudspeaker (red lines). The emitted signal and its echoes from the target are recorded using the 1/7-scaled MDH (blue lines). The recorded binaural sounds, whose pitch is converted to 1/8 of the original by lowering the sampling frequency, are presented to the participants through headphon Credit: Sumiya et al, 2021, PLOS ONE (CC-BY 4.0, https://creativecommons.org/licenses/by/4.0/)