Hello and welcome to HCM,
You need to take history from your son whether he is aware of his strange blinking habit.
Frequent blinking or twitching is seen in a special kind of
epilepsy and this kind of blinking is actually a
seizure.
In this kind of seizure, there is no
loss of consciousness, the person remains conscious and seizures are in form of frequent blinking and dazzling for fraction of second.
The person is not aware of the seizure.
This is one of the possibility.
Other possibility is that of a local condition wherein the
nerve supplying the eye lid is irritated and manifests in the form of twitching.
I suggest you to consult an ophthalmologist first.
If the condition is not localized, you will have to consult your physician for clinical assessment and thus management.
Thanks and take care
Dr Shailja Puri