Tunnel vision
From Free net encyclopedia
Image:Human eyesight two children and ball normal vision.jpg Normal vision. Courtesy NIH National Eye Institute
Image:Human eyesight two children and ball with retinitis pigmentosa or tunnel vision.png The same view with tunnel vision from retinitis pigmentosa.
Tunnel vision is a visual problem or symptom of another problem which produces loss of peripheral vision, as illustrated.
Tunnel vision can be caused by:
- retinitis pigmentosa, a disease of the eye.
- sustained (1 second or more) high accelerations, resulting in peripheral light loss. [1]. Can occur in fighter pilots during combat or testing situations. More severe symptoms can include loss of consciousness.
- hallucinogenic drugs.
- glaucoma, a disease of the eye.
- Extreme fear or distress, most often in the context of a panic attack.
- altitude sickness, hypoxia in passenger aircraft [2]
- exposure to oxygen at a partial pressure above 1.5-2 atmospheres, producing central nervous system oxygen toxicity, notably while diving. [3] Other symptoms can include dizziness, nausea, blindness, fatigue, anxiety, confusion and lack of coordination.
- Flying a plane with a centripetal acceleration of up to or over 39 m/s2 (4gs) with the head towards the center of curvature.
- Other loss of blood to the brain.
- Orolonged exposure to air contaminated with heated hydraulic fluids and oils, as can sometimes happen in passenger aircraft [4].
When combined with piloting an aircraft, driving, crossing roads or operating heavy machinery, the consequences have been known to be fatalTemplate:Fact.
Tunnel vision is a metaphor for narrowmindedness, particularly in describing those who pursue an investigation with their conclusion already decided and proceed by only accepting evidence that supports their conclusion and excluding any evidence that contradicts their assumptions.
Tunnel vision is also a (positive) metaphor for the largely intuitive ability to focus only on what is crucial and relevant to solving a problem. To put this another way, it's the ability to ignore a distracting lack of knowledge while learning just enough to solve a problem.
The term is widely used this way in the software industry.