Does your daughter have a diagnosed seizure disorder? Flashing lights are one of the classic seizure triggers, so common that they're even used during EEG's to stimulate seizure activity. The behavior you're describing certainly does sound like a classic tonic-clonic seizure.
If your daughter hasn't been evaluated, you need to have this done. She needs to be seen by a neurologist, who will likely want to do further testing. If she is having seizures, it's likely they can be controlled with medication.
If she is already under treatment, please discuss this with her neurologist, as she may need a medication adjustment.
In most jurisdictions, people with seizure disorders are allowed to drive if they have been seizure-free for a specified period - usually six months to a year. But the first thing is to get the episodes under control.
Good luck, and let us know how she does.
Ulcerative colitis forum co-moderator
Moderate to severe left-sided UC diagnosed 2001. Flared for 5 years, finally in remission with Remicade since March 2006. Colazal, Remicade, Nature's Way Primadophilus Reuteri.
Avascular necrosis in both shoulders is my "forever" gift from steroids.
Chronic joint/connective tissue/muscle pain; TKR 05/09
"My life is an ongoing medical adventure"