<p>Both blind and sighted persons may use echoes for detecting objects.</p><p>The effect of object size on echolocation was tested in a listening</p><p>experiment with 15 sighted participants. Noise burst of 500-ms were</p><p>generated and recorded in an ordinary room, with and without a</p><p>reflecting object. The diameter of the reflecting object was 0.25 or</p><p>0.50 m, and it was located at a distance of 0.5, 1, 2, 3 m from the</p><p>microphones. Pairs of sounds, one with and one without the object,</p><p>were presented to the listeners. Their task was to decide which of the</p><p>two sounds that were recorded with the reflecting object. The results</p><p>showed that it was harder to detect the 0.25 than the 0.5 m object, and</p><p>that performance generally decreased with distance. The auditory</p><p>angle, which is a function of the size to distance ratio, was found to</p><p>predict detection performance fairly well.</p><p>Sighted</p>

Both blind and sighted persons may use echoes for detecting objects. The effect of object size on echolocation was tested in a listening experiment with 15 sighted participants. Noise burst of 500-ms were generated and recorded in an ordinary room, with and without a reflecting object. The diameter of the reflecting object was 0.25 or 0.50 m, and it was located at a distance of 0.5, 1, 2, 3 m from the microphones. Pairs of sounds, one with and one without the object, were presented to the listeners. Their task was to decide which of the two sounds that were recorded with the reflecting object. The results showed that it was harder to detect the 0.25 than the 0.5 m object, and that performance generally decreased with distance. The auditory angle, which is a function of the size to distance ratio, was found to predict detection performance fairly well. Sighted