Final answer:
The trance-like state a motorist may experience after long periods of driving is called 'highway hypnosis' and can be prevented by taking breaks and avoiding fixed gazes. Sleep deprivation worsens this condition, leading to a decline in alertness and motor skills.
Step-by-step explanation:
When a motorist has been behind the wheel for a long time, he/she may experience a trance-like state which is often referred to as ‘highway hypnosis.’ Highway hypnosis occurs due to the monotony of driving for extended periods and can lead to reduced attention to the road, increasing the risk of accidents. To prevent this state, it's advisable for drivers to avoid looking at any one thing for more than a few seconds and to take regular breaks to ensure alertness. Factors such as sleep deprivation can exacerbate the risk, as sleep-deprived individuals have impaired cognitive and motor functions that are akin to being under the influence of alcohol. This impairment can be especially dangerous when operating a vehicle or machinery.