2010 BC Guide in Determining Fitness to Drive

Example: depressing the brake pedal in response to a child running outon the roadway, swerving to avoid an animal on the road, etc.Research on motor functions and driving indicates considerable variabilityin the association between the different motor functions and drivingoutcomes. Overall, the research suggests that a significant level ofimpairment in motor functions is needed before driving performance isaffected to an unsafe level.Sensorimotorfor purposes of the Driver Fitness Program, sensorimotor functions areconsidered as a subset of motor functions.sensorimotor function is a combination of sensory and motorfunctioning for accomplishing a task.sensorimotor functions are, for the most part, reflexive or automatice.g., the response to your hand being placed on a hot stove; ability tosit upright, etc.vestibular disorders and peripheral vascular diseases commonly resultin sensorimotor impairments.Sensory functions (Vision)Visual functions important for driving include:Acuitythe spatial resolving ability of the visual system, e.g., the smallest sizedetail that a person can see.visual acuity typically is assessed by having the person read a letterchart such as the Snellen chart, where the first line consists of one verylarge letter, with subsequent rows having increasing numbers of lettersthat decrease in size.Visual fieldrefers to an individual’s entire spatial area of vision when fixation isstable, e.g., the extent of the area that an individual can see with theireyes held in a fixated position.Contrast sensitivitythe amount of contrast an individual needs to identify or detect anobject or pattern, e.g., the ability detect a gray object on a whitebackground or to see a white object on a light gray background.22