As people age, a steady decline may occur in certain skills that are important for safe driving. Beginning at around age 55, an individual's ability to process information, to remember, and to make judgments in traffic situations, such as determining the distance and approach of oncoming vehicles and pedestrians, gradually decreases. Furthermore, vision decreases, strength and flexibility diminishes and it takes longer to react to unexpected situations.
 
Functional and physical decline related to aging does not, however, affect all drivers at the same rate or in the same way. Although specific abilities needed to drive safely, such as vision, memory, physical strength, reaction time, and flexibility, decline as people age, the rate of change varies greatly.
 
This page describes what drivers can expect as they age in regards to a variety of functions and skills required to safely operating a motor vehicle.

Vision
Vision is the primary sense used in driving. Visual declines represent the most significant losses for older drivers who generally need more light to distinguish features along the roadway and must be closer to read signs and follow other traffic cues. Older eyes also need more time to recover from the glare of bright headlights at night. Drivers over 50 years of age should have their eyes checked every year or two by an optical specialist.
 
Following are tips for wearing glasses or contact lenses:

• Always wear them when you drive, even if you are only going a short distance. If your driver’s license says you must wear corrective lenses and you do not, you could get a ticket if you are stopped by a law enforcement officer.
• Try to keep an extra pair of glasses in your vehicle. Then, if your regular glasses are broken or lost, you can drive safely. This also can be helpful if you do not wear glasses all the time and you forget to take them with you when driving.
• Do not wear dark glasses or tinted contact lenses at night, even if it is to help with glare. They shut out too much of the light you need to see clearly.

Cognition
Cognition involves perception, attention, learning, memory, thought, visual processing, reading, and problem solving. Driving is a complex activity requiring many of these skills. Drivers must remember how to operate their vehicle, what the signs and signals mean, know their destination and how to get there, all while processing other information.

Dementia
Dementia affects several critical abilities needed for safe driving including perception and visual processing, an ability to maintain attention and respond to multiple stimuli, an ability to make correct decisions and the ability to act appropriately in difficult traffic situations. Individuals in the early stage of dementia may be able to operate a vehicle under normal circumstances, but have difficulty with changing circumstances, and may often become lost.

Motor Function
Aging can affect muscle strength, endurance, flexibility and range of motion, skills that are needed for driving safely. A loss of any of these skills makes it harder to control the vehicle. Driving also requires flexibility such as turning the head to back up or change lanes. Aging causes muscles to stiffen making even simple movements more difficult.

Additional information that may be relevant includes: