Final answer:
Monaural cues are the changes in sound frequency that relate to how sound waves bounce off the pinnae. They help us locate sounds that occur above or below, and in front or behind us.
Step-by-step explanation:
Changes in sound frequency that relate to how those waves bounce off the pinnae are known as monaural cues. The pinna (outer ear) interacts differently with incoming sound waves depending on the sound's source relative to our bodies. Monaural cues help us locate sounds that occur above or below, and in front or behind us. For example, if a sound is directly above you, the sound waves received by both ears would be identical. If the sound is below you, the sound waves would have a different interaction with your pinnae, resulting in a change in sound frequency. This change in frequency provides a cue that helps us determine the direction of the sound.