The study links a possible connection between light sensitive retinal nerve cells and nerve cells in the brain that are responsible for the perception of migraine pain.  The study noted that blind patients also avoided light when suffering from a migraine, however blind patients that had lost their eye did not avoid light.  The authors concluded that some of the retinal axons, included some light sensitive axons were sending signals to the hypothalamus, a part of the brain that is responsible for the perception of headache pain.