If he hears things that aren't there and sees things that aren't there, that is a psychotic disorder and needs serious medication.
If you listen to the Tony Attwood radio interview link I posted, you will hear him explain this exact phenomenon - too often, those on the spectrum (especially the younger ones) are misdiagnosed as having a psychotic disorder, because of a conflict between the way the question is asked, and the very literal way an Autism Spectrum Disorders (ASD) person's mind works. I know I spent a lot of time in my childhood trying to analyse exactly what was the 'voice' of my inner thoughts. I had what can only be called a "phonographic" memory, I could mentally replay conversations and hear the various voices in my mind. Or I could imagine what a particular person might say, and mentally 'play' that person saying those words. I still use this now, in my writing - I have my characters mentally play-act, and I just write it down.
The problems come when the person 'hearing' these voices cannot distinguish between imagination and reality.
Also in that interview - Tony Attwood pointed out that about 1 in 5 kids on the spectrum have an imaginary friend. And tis is okay when a kid is five, but often seen as a concern (by therapists who don't get these kids) when the child is 15.
Perception of reality is the issue here.
I do recall also - difficult child 1 has a "phonographic memory". We could ask him about some fact or other from a TV documentary and he would mentally replay it in his head until he got to the relevant bit. difficult child 3 does something similar - he is actually an amazing mimic for accents. So is their middle sister (a possible Aspie). She 'practices' various accents and dialects at work and tries them out on the customers to see how accurate she can be. She reports success when a customer asks her how long she has been in Australia from [whichever country whose accent she has been practising].
A younger child especially, will often report their own detailed analysis of their thought processes in ways that can be a worry, unnecessarily so.
I do remember saying to my mother that sometimes the sound of my own thoughts was confusing, and I didn't understand why there were different voices when really, the thoughts were also silent. And difficult child 3 at age 17 when studying for his final high school exams, came in for lunch from his room and said he had to take a break because "I'm concentrating so hard, the silence in my head is deafening and distracting me."
I am neither bipolar nor schizophrenic. I have never had a psychotic break (or come close to one). But I do remember self-analysing in detail when very young, but not always having the words to describe the phenomena of my own thoughts. As soon as I realised that people around me did not understand my questions, or were only going to give me platitudes for answers, I stopped being open about my queries.
I still remember playing with my two imaginary friends. I remember what they looked like, I remember the games we played. I was riding my dinky and they each had one too. I would get very cross if my sisters walked where my friends were playing - I carefully marked out where they were so people wouldn't walk through them. We also played tea parties and had detailed conversations. As Tony Attwood said - in a three year old or four year old, people smile and think it's cute. Or if they're idiots, they panic about breaks with reality... but Autism Spectrum Disorders (ASD) kids often do the same sort of things other kids do, but at a different age. And a ten year old or 15 year old playing with imaginary friends can have parents rushing to the psychiatrist for antipsychotic medications... when really, it is perhaps just an AD kid with fewer social inhibitions who doesn't know it's not COOL to have imaginary friends when you're a teenager.
Or a kid can be role-playing, perhaps with his Star Wars figurines or similar. Again, not cool in your teens, but Autism Spectrum Disorders (ASD) kids don't know that. I often hear difficult child 3 talking aloud and role-playing with various toys. He is aware it sounds odd and does try to hide it though.
According to Tony Attwood, 12 is far too young for a diagnosis of schizophrenia. There is often a far more likely explanation but it can require some lateral thinking to find it.
Marg