A friend feels a light like neon strip that start small in his eye&then start growing until it vanish&he starts yawning hardly during that. this happened years ago once but it more than once in the last 2 months. he don't want to visit dr. causes plz?

My first hunch is that he having a migraine headache aura without the headache. Tell him his body is talking to him and to listen at take good notes such as does he have a headache after? What brings it on. What makes it better. Recommend he see a Dr as you are his friend.

There is insufficient information to assess this situation--length of the episodes, frequency, associated symptoms, unilateral vs. bilateral. That said, it seems most like a migraine (equivalent). If episodes worsen or do not resolve, you should encourage an evaluation by a physician.