Neurological Problem with 12-year-old brother! HELPPPP!? pleaseee!?

Ok, so ever since I can remember, my brother has been doing this weird thing. He will be talking to me one minute, then he'll stop talking and his face is like a blank gaze, his head starts tilting back, and his eyes get a little squinted. It only lasts for a few seconds then when its over, he forgets what he was saying at first..Sometimes he even gets a little wobbly and almost falls over! It's really worrying and i have NO IDEA what it could be! I would TRULY appreciate it if anybody could tell me what it could be!!!!!!!!!! thank you, (: