Final answer:
Sound localization is determined by interaural time difference and interaural intensity difference, which the brain stem's auditory nuclei calculate to determine the source of a sound.
Step-by-step explanation:
Understanding Sound Localization
Sound localization is a vital auditory process that allows an organism to determine the source of a sound. This process involves the auditory nuclei performing central processing in the brain stem to calculate two critical binaural cues: the interaural time difference and the interaural intensity difference.
When a sound is located off-center, it will arrive at the closer ear slightly before the other, producing a time difference known as the interaural time difference cue, key in sound localization on the horizontal plane. Moreover, the sound will be perceived as louder in the ear closer to the source, due to some sound waves being blocked by the head. This phenomenon is termed the interaural intensity difference cue, which also aids in horizontal sound localization by comparing relative loudness at both ears.
These auditory mechanisms are crucial for everyday activities that require spatial hearing, such as determining the position of a moving vehicle or locating a person talking in a crowded room.