thumb|right|Open road in [[New Zealand]]

Highway hypnosis, also known as white line fever, is an altered mental state in which an automobile driver can drive lengthy distances and respond adequately to external events with no recollection of consciously having done so.

It appears that in this state, the driver's conscious attention is fully focused elsewhere, yet their brain is still able to process a significant amount of information related to the road and vehicle control on a subconscious level. Highway hypnosis is a manifestation of the common process of automaticity, the ability to perform complex actions without being consciously aware of the processes involved to do them. In some cases, the trance state in a driver can be so deep that auditory and visual distortions occur.

History

The idea of a hypnotic trance while driving was first described in a 1921 article that mentioned the phenomenon of "road hypnotism": driving in a trance-like state while gazing at a fixed point. A 1929 study, Sleeping with the Eyes Open by Walter Miles, also addressed the subject, suggesting that motorists could fall asleep with their eyes open and continue to steer.

The idea that this phenomenon could explain the unaccountable automobile accidents became popular in the 1950s. The term "highway hypnosis" was coined by G. W. Williams in 1963. Building on the theories of Ernest Hilgard (1986, 1992) that hypnosis is an altered state of awareness, some theorists hold that the consciousness can develop hypnotic dissociation. In highway hypnosis, one stream of consciousness drives the car while the other deals with other matters. Partial or complete amnesia related to the time spent driving under highway hypnosis can develop for the driver involved.

In contemporary international scientific literature, the term "highway hypnosis" is increasingly being replaced by "driving without attention mode" (DWAM).

  • Monotonous engine noise and car swaying
  • Driver fatigue
  • Driving alone or with passengers who have fallen asleep (absence of distracting factors)
  • A relaxed driver state or, conversely, severe stress, as well as problems occupying all the driver's attention
  • The ability to drive without the need for intense concentration (e.g., on highways without intersections or traffic lights) or with few cars on the road and on familiar road sections, as opposed to newer drivers and on roads in unfamiliar areas.

Experimental studies have shown that highway hypnosis is less likely due to monotonous landscape and uniformity of the road than to predictability of the situation for the driver. For example, if a driver has to drive in the day on a curvy road, but they have previously driven on this road many times in dark, highway hypnosis is more likely to occur. In this state, there is a tendency for the driver to gradually increase speed (a phenomenon known as psychological inertia of speed). In this case, the driver may not be aware of their fatigue or that they are falling asleep.

External signs

Thanks to experimental research on the phenomenon of highway hypnosis, external signs of a trance state in a driver have been identified:

  • Driver stares intently at the road, with their head tilted forward, or the driver suddenly makes a sudden, jerking head movement.