L
There are two Communicating activities in the physical section.
The first deals with the claimant providing information to another person, typically those assessing the claim will be looking at the claimant's abilities in speaking, writing, typing, or other means which are normally, or could reasonably be, used, unaided by another person.
The second looks at the claimant's ability to receive information verbally, by lip reading, 16-point print or braille.
I've checked a variety of DWP documents and can't find a definitive view as to whether ASD is considered a physical issue or not, you will certainly need to argue that it is. What I can say is that neither is about social interaction but specifically sensory impairment.
Also, stick to the legal definitions, what is being assessed; simple versus complex information. If you don't think these activities apply to your son then it is usually best not to try claiming them as it can devalue your whole testimony.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems 
