They didn't need to go to the trouble to "discover" that: they could have asked me. I lost my hearing at age 17 and, in response, my brain increased its abilities 10-fold, easily, so that I'm now the smartest man on the planet. Why, yes, I am wearing my underwear outside of my pants. Why do you ask...?
No, seriously, I did lose my hearing. I found that I compensated for it by paying way more attention to non-verbal cues. For example, I can tell before an interviewer even knows it, himself, that I'm not gonna get the job. I can also see it, clearly, when someone's trying to BS me. You also learn introspection, since you don't have the auditory distractions.