Hi, i've been wondering for a while now about something.
In the last year since he turned 4 (he will be 5 soon), DS (asd) started making some good progress with speech and language, and his play started developing at the same time.
It still is delayed in comparison to his peers, but we are now seeing some basic role-play and a little more imagination with play than previously, whereas before his play was very concrete or sensory orientated.
Anyway, despite much better playing skills, he still has lots of moments every day where he reverts back to his basic type of play. 
Here are some examples of what he does.
He often carries small toys or objects around, and will wander about twirling the object or simply holding it and looking at it, while humming a tune, or doing soft grunts/throat noises while blowing through his nose at the same time (sorry hard to explain but it's the same sort of sounds over and over).
He always has liked carrying and fiddling household things, random stuff like the tin-opener which he will spin the handle, or the wine bottle-opener he likes to turn the moving parts too,... or earlier he had taken the toy umbrella from DD's dolls' house and was spinning it with one finger while wandering around without a specific purpose.
The other day i was trying to get himm to do some creative stuff with PlayDoh but he was only interested in twirling and spinning the playdoh roller and cutter; or he will move his cars and trains back and forth simply to look at the wheels,....
The thing is he is now able to do better much play than that by himself, and especially if an adult guides the play, but when he isn't particularly engaged in anything what i've described above is what he will do.
Do you think it is a form of self-stimulatory behaviour through play?
Anyone noticed similarities with your dc?
Thanks. 