Comparison of Echolocation Abilities of Blind and Normally Sighted Humans using Different Source Sounds

The ability of some humans to echolocate has become widely known primarily due to a small number of famous expert echolocators who are capable of extraordinary feats. However, a lesser-known fact is that all humans exhibit this skill unconsciously and can learn it relatively quickly and implicitly through repeated practice. In our experiments we tested groups of 12 blind and 14 sighted untrained participants in a simple echolocation test – localizing a 1m x 2m vertical wall at distances between 1 and 3 meters using 10 different types of sounds as the source signals for the echolocation attempts. There were significant differences between the participant groups and between some of the tested sounds. Although the groups were small, a clear difference was also observed between the experienced totally blind participants and the legally blind visually impaired participants that had residual light sensitivity. From the compared sounds 3 kHz and 4 kHz synthetic percussion sounds, pink and blue noise were among the sources that led to the highest chances of correctly guessing the obstacle’s direction and distance.