Tachypsychia

Tachypsychia is a neurological condition that alters the perception of time, usually induced by physical exertion, drug use, or a traumatic event. It is sometimes referred to by martial arts instructors and self-defense experts as the Tachy Psyche effect. For someone affected by tachypsychia, time perceived by the individual either lengthens, making events appear to slow down, or contracts, objects appearing as moving in a speeding blur. It is believed that tachypsychia is induced by a combination of high levels of dopamine and norepinephrine, usually during periods of great physical stress and/or in violent confrontation.

Physical responses

Also called the "fight or flight" response of the body to an event our mind considers life-threatening, tachypsychia is believed to include numerous physical changes.

Adrenaline response

Upon being stimulated by fear or anger, the adrenal medulla may automatically produce the hormone epinephrine (aka adrenaline) directly into the blood stream. This can have various effects on various bodily systems, including:

• Increased heart rate and blood pressure. It is common for a tachypsychia subject's pulse to rise to between 200 and 300 beats per minute (bpm). Increased heart rate (above 250 bpm) can cause fainting, and the body may adduct all limbs, adopting fetal position, in preparation for a coma.
• Dilation of the bronchial passages, permitting higher absorption of oxygen.
• Dilated pupils to allow more light to enter, and visual exclusion—tunnel vision—occurs, allowing greater focus but resulting in the loss of peripheral vision.
• Release of glucose into the bloodstream, generating extra energy by raising the blood sugar level.

It is common for an individual to experience auditory exclusion or sensitivity. It is also common for individuals to experience an increased pain tolerance, loss of color vision, short term memory loss, decreased fine motor skills, decreased communication skills, or decreased coordination.

Psychological response

The most common experience during tachypsychia is the feeling that time has either increased or slowed down, brought on by the increased brain activity cause by epinephrine, or the severe decrease in brain activity caused by the "catecholamine washout" occurring after the event.

It is common for an individual experiencing tachypsychia to have serious misinterpretations of their surroundings during the events, through a combination of their altered perception of time, as well as transient partial color blindness and tunnel vision. After the irregularly high levels of adrenaline consumed during sympathetic nervous system activation, an individual may display signs and symptoms of post-traumatic stress disorder, and it is common for the person to display extreme emotional lability and fatigue, regardless of their actual physical exertion.

It is possible to manage tachypsychia still occurring after the event, and it is common for soldiers and martial artists to use tachypsychia in order to increase their performance during stressful situations.

References

For example, popular military writer Richard Marcinko, "Seal force Alpha", page 272.