I concentrate much better with tunes playing in the background or via headphones; partially because my ears ring if there's not some type of 'white noise', and partially because it helps me fully ignore everyone around me rather than zoning out like I sometimes do. I've got ADHD, so having something to keep me focused usually helps – thus why I'm asking this question.

Also, I'd be using headphones while taking the test so as to not be rude to the other takers.

A couple years ago i went and got this test done that checked for nerve damage in my ears. They found nerve damage in my left ear. My mom notice something was wrong when i was a baby. But they didn't know all of this. I have deafness. It is mild to moderate hearing loss, 40 to 50 db loss. db=decibels.

brainstem auditory evoked response (BAER) test – can diagnose hearing ability and can indicate the presence of brain stem tumors and multiple sclerosis. Electrodes are placed on the scalp and earlobes. Auditory stimuli, such as clicking noises and tones, are delivered to one ear.

That is the testing i had done.
I wear a hearing aid for my left ear.
Also i am 21 years old.
I also have mild mental retardation,deafness,communication disorder,adhd,sensory issues.