Hi A.,
I agree with the doc that it may be an underdeveloped (or agravated) nervous system. At this age, babies are very sensitive to the neurotoxins that most of us have gotten use to over the years. Any cleaning supply, laundry detergent, baby bath or shampoo or any other body product, even something that you use because you are so close, can exacerbate a neurological issue if it is not non-toxic to humans.
Sythetic chemicals build up in our systems and don't just give us a symptom here and there, but can develop into something else down the road. Because of the numerous things on the market, there is no way to tell in what combination these chemicals will cause what issue. What I always advise, get rid of them all. Detoxing can be very simple and inexpensive and it will not only help your little one, but everybody else in the household. If you want more information, feel free to get back to me. I'd love to help.
God bless,
M.