Chris Girkin, M.D., MSPH, FACSOne of the scaries of aging is the change in night vision over time. Most people start noticing changes in night vision around the age of 45. The most common complaints regarding nighttime driving are difficulty with oncoming headlights, judging distances or speeds, and seeing lane markings or street signs clearly. 

What Causes Night Vision Changes?

  1. As we age, it takes longer for our eyes to adjust when going from bright to dark conditions. For night driving, this means it is harder to see after being hit with bright headlights.
  2. Decreased contrast sensitivity. Contrast sensitivity is our ability to decipher an object from its background. As we age, our contrast sensitivity decreases, and this can make objects in dim lighting more difficult to detect. That street sign that’s harder to see at night? That’s because of decreased contrast sensitivity.
  3. Increased higher order aberrations (HOAs). An HOA is an irregularity experienced by a wave of light as it passes through an eye. At nighttime, our pupils get bigger. And as the pupil gets bigger, HOAs can increase. Those halos, starbursts, or terrible glares you see around bright street lights or headlights? That can be explained by increased HOAs at nighttime.

Tips for Safer Night Driving

  1. If you wear glasses or contacts, make sure your prescription is up to date.
  2. Make sure your windshield and mirrors are clean and clear. Dirty glass scatters light which can make nighttime driving worse.
  3. Use the night setting on your rearview mirror. (Yes, this is actually a thing and is very helpful. Consult your manual if you don’t know how to switch this over to night mode).
  4. Avoid the gimmicks. You’ve probably seen commercials for yellow-tinted night glasses to improve glare and contrast while driving at night. There is a lack of evidence that these actually work. In fact, these devices can decrease the amount of light that enters into the eye making it harder, not easier, to see at night.

Treatments for Night Vision

First and foremost, get an eye exam and ensure your vision is corrected as best as possible. Whether it’s glasses or contact lenses, make sure your prescription is up to date. If you wear prescription glasses, ask about adding an anti-reflective coating which can help cut down glare at night. If you have cataracts (a condition where the natural lens in your eye becomes cloudy), these often affect nighttime driving, and cataract surgery can certainly improve your night vision.

A Symptom of Something More Significant?

Could poor night vision be a sign or symptom of something more significant? Absolutely. Anyone with difficulty driving at night should schedule a comprehensive eye exam with an eye doctor. Conditions such as cataracts, glaucoma, or macular degeneration can all cause difficulty driving at night. The earlier that can be detected and treated, the happier you’ll be with your vision. 

Thank you to the Birmingham Mom Collective for their participation in this article.