Thank you everyone for your reply. I appreciate the wealth of knowledge and support here. I will definitely check out the resources recommended.

Yes, anxiety definitely seems to be the big issue here.

Interesting point about the speech part too. DS is much more into the analytical side of languages rather than actually using it. He is exceptional in decoding, spelling, identifying word origins, etc., but his everyday speech is no more advanced than an average Kindergartener. He memorizes maps, the periodic table, but is not as into stories. Most of the time I chalk this up to asynchronous development ("some boys develop their verbal abilities later"), but sometimes do wonder if there is a deficit somewhere which he is trying to compensate by going so far into the other end.

One more question: in looking into therapists, how important it is to find one who is familiar with gifted children?