Highway hypnosis, also popularly known as driving without attention mode (DWAM) or white line fever, is a mental state in which a person can drive a truck

Truck

A truck or lorry is a motor vehicle designed to transport cargo. Trucks vary greatly in size, power, and configuration, with the smallest being mechanically similar to an automobile...

 or automobile

Automobile

An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...

 great distances, responding to external events in the expected manner with no recollection of having consciously done so. In this state the driver's conscious mind is apparently fully focused elsewhere, with seemingly direct processing of the masses of information needed to drive safely. Highway hypnosis is just one manifestation of a relatively commonplace experience, where the conscious and unconscious minds appear to concentrate on different things.

In some parts of the Southern United States

Southern United States

The Southern United States—commonly referred to as the American South, Dixie, or simply the South—constitutes a large distinctive area in the southeastern and south-central United States...

, the phenomenon is called white-line fever, in reference to the white lines painted on the pavement.

Building on the theories of Ernest Hilgard

Ernest Hilgard

Ernest Ropiequet "Jack" Hilgard was an American psychologist, professor at Stanford university, who became famous in the 1950s for his research on hypnosis, especially with regard to pain control...

 (1986, 1992) that hypnosis

Hypnosis

Hypnosis is "a trance state characterized by extreme suggestibility, relaxation and heightened imagination."It is a mental state or imaginative role-enactment . It is usually induced by a procedure known as a hypnotic induction, which is commonly composed of a long series of preliminary...

 is an altered state of awareness

Awareness

Awareness is the state or ability to perceive, to feel, or to be conscious of events, objects or sensory patterns. In this level of consciousness, sense data can be confirmed by an observer without necessarily implying understanding. More broadly, it is the state or quality of being aware of...

, some theorists hold that the consciousness

Consciousness

Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...

 can develop hypnotic dissociation. In the example of highway hypnosis, one stream of consciousness is driving the car while the other stream of consciousness is dealing with other matters. Amnesia

Amnesia

Amnesia is a condition in which one's memory is lost. The causes of amnesia have traditionally been divided into categories. Memory appears to be stored in several parts of the limbic system of the brain, and any condition that interferes with the function of this system can cause amnesia...

 can even develop for the dissociated consciousness that drove the automobile. The phenomenon is an example of automaticity

Automaticity

Automaticity is the ability to do things without occupying the mind with the low-level details required, allowing it to become an automatic response pattern or habit. It is usually the result of learning, repetition, and practice....

 in cognitive psychology

Cognitive psychology

Cognitive psychology is a subdiscipline of psychology exploring internal mental processes.It is the study of how people perceive, remember, think, speak, and solve problems.Cognitive psychology differs from previous psychological approaches in two key ways....

.