As we all know, Parkinson’s disease is mainly characterized by involuntary movements of the body and loss of control over motor functions. As a neurodegenerative disorder, Parkinson’s disease is due to the loss of brain cells that produce dopamine. And so it’s only natural that anyone who has it will exhibit progressive deterioration of their motor functions, thus explains the involuntary movements. However, while its cause is still very much unknown, the disease has a lot of symptoms, both motor and non-motor. In fact, according to Parkinson’s UK, the condition can also show in the person’s eyes and vision. And so, while often unrelated to the disease itself, the three eye symptoms listed below can give you a clue if you are at risk of having Parkinson’s disease. Double vision Perhaps the most far-fetched symptom, double vision happens when the person sees a double image of an object either most or all of the time. For people with this condition, the two images they see may be on top of each other or side by side. And while there are other conditions that cause double vision (diabetes, thyroid problems), this can also be caused by muscle fatigue and when our eyes do not move smoothly. Nevertheless, check with your doctor or ophthalmologist if the problem persists. Color vision Also called “color blindness,” this condition is a person’s inability to see and distinguish different colors from each other. However, very few people are completely color blind and oftentimes, people just can’t differentiate certain colors. The most common in particular have to do with the shades of red and green, while shades of blue and yellow are much less common. It’s caused by the lack of light-sensitive pigments in our eye's photoreceptors found in the retina. Dry eyes As another subtle symptom, people who are developing (or already have) Parkinson’s disease may not realize that they are blinking too often than the average person. Because blinking helps clean the eyes, doing it less often can cause dirt buildup, which can only further damage both your eyes and your vision. Source
