Structured Reflected Sound

Structure reflected sound is used by our brain to perceive properties of silent objects. It is the use of obstructed sound which has been reflected away from our ears. An acoustic hole is left where the obstruction is positioned. The book states, "while you may not have ever actively echolocated until today, your brain is likely using reflected sound all the time, mostly without your conscience awareness." It doesn't necessarily determine the size or shape of objects through reflected sound but it informs you of major structures in your immediate surroundings.