I had this type of impairment until I was 28, and I never heard it described like this, so I don't know if it is dissociation or not. But I'll try to describe it here...
See, I couldn't hear people or see people right. Like I couldn't hear conversation, but if people spoke directly to me, I could. Also, people were like shadows to me. For example, if it was a stranger, I couldn't see what they were wearing or their body language... I just saw an random entity.
Like I said, I came out of it when I was 28, so It couldn't be autism. I think it came from extreme withdrawal from people, but it was real physical symptoms. I couldn't hear conversations no matter how hard I tried, so it was like auditory processing disorder (APD). I think I still have APD mildly, but not have as bad as before 28.