It depends on what kind of bright light you are talking about and how bright it is. Not every kind of bright light can cause cataracts. It is more common to increase the risk of getting cataracts if long time exposing to UV radiation. As to some bright light, for example, the fluorescents with diffusers used in our daily life won't cause permanent damages to our eyes because the light spreads at a wide range instead of pointing at one direction. But bright light is indeed harmful to our health. Long time exposure to bright light might cause mania, which is very risky. Mania refers to a condition, which is an abnormal mood that people would get exaggerated emotion over a small stimulation. They could be too happy, too hyper or too stressed with rapid speech and have difficulty in concentration. Besides, bright light might cause problems like eye burn, sleep disturbance, eye strain and headache. In some serious cases, people might even have suicide thoughts.