Much like bats and dolphins, some people have developed the ability to analyze bouncing sound waves to generate a picture of their environment. Advanced echolocators have shown increased mental activity in parts of the brain usually devoted for vision. | How Human Echolocation Allows People to See Without Using Their Eyes
Daniel Kish has been blind since he was a baby but that hasn't stopped him living an incredibly active life that includes hiking and mountain-biking. To do this, he has perfected a form of human echolocation, using reflected sound waves to build a mental picture of his surroundings.