Interaural level differences (ILD) refer to the variations in sound intensity that reach each ear when a sound source is located to one side of a listener. When a sound originates from one side, the ear closer to the source receives a louder sound compared to the ear on the opposite side. This difference in loudness helps the brain determine the direction of the sound. The brain processes these differences in intensity to localize sounds in the environment. ILD is particularly effective for high-frequency sounds, as they are more easily blocked by the head, creating a more pronounced difference in volume between the ears.