Auditory System Structure and Processing (6A) Practice Test

Researchers tested sound localization while participants wore an insert earplug in the right ear that attenuated incoming sound by ~15 dB without distorting frequency content. When brief clicks were presented from speakers positioned in the horizontal plane, participants systematically reported the clicks as originating more toward the left than the true source, especially for sources near the midline. Based on the study setup, which conclusion about auditory processing is most consistent?

In a dichotic listening experiment, two different syllables are presented simultaneously, one to each ear. When participants are instructed to shadow (repeat) the syllable presented to the right ear, they are accurate; when instructed to shadow the left ear, accuracy drops, even though overall hearing thresholds are normal. Based on the task demands, which conclusion about auditory processing is most consistent?