Hi lynxgal,
I'm not a Dr. but I think what they are trying to say is that your seizures may be triggered by photosensitive matters, that's when bright light can trigger seizures. The reason why they are probably saying within is because the e.e.g will read 8 areas of the brain and some of the areas are in the normal reading range while possibly there may be more electrical activity in other parts of the brain. For example my e.e.g. always shows more electrical activity in the right temporal lobe because that's the area that's triggering my seizures. I hope I have been of some help. I wish you the best of luck and May God Bless You!

Sue