Auscultation is the examination of internal organs by listening. Usually this involves using a tool to magnify the sound - such as a stethoscope, but internal sounds can be detected by placing the ear over the region of body closest to the organ under examination. The examiner will detect abnormalities such as increased or decreased loudness, abnormal timing of sounds, or unusual sounds. The procedure is most often used when examining the heart, lungs and gastrointestinal tract.