Auditory System Structure and Processing (6A) Practice Test

A localization experiment tested sound direction processing using low-frequency (200 Hz) tones presented from left or right. When the researchers introduced a small, fixed delay to the right-ear headphone channel (without changing intensity), participants increasingly reported the sound as coming from the left. Which statement best explains the auditory phenomenon described?

In a study of cochlear frequency selectivity, investigators presented a 3000 Hz tone and measured detection thresholds while adding narrowband noise centered either at 3000 Hz or at 800 Hz. Detection thresholds increased markedly with noise centered at 3000 Hz but only slightly with noise at 800 Hz. Which statement best explains the auditory phenomenon described?