9.2 Human Performance & Limits Flashcards
What is the Cornea ( Eye )
The window @ the front of the eye, which focuses what you see by between 70% and 80%
What does the Iris & pupil do?
Controls the amount of light entering. Can be adjusted by a factor of 5:1
What the the lens do?
Changes the shape of light ( Accommodation ) and does the final focusing
What happens when a person is tired ( regards to accommodation )
Image becomes less sharp. blurred vision
What does the Retina do?
Connects Nerve cells at the back of the eye to the optic nerve
Aspects of Rods
- Black & white
- High sensitivity in low light
- Very good peripheral vision
Aspects of Cones
- Central Vison
- Fine details
- Colour sensitive
What is short sighted
( Near Sight / can’t see far away ) known as Myopia
What is long sighted
( Far sighted / Can’t see close ) Known as Hypermetropia
What is Visual Acuity?
Ability to discriminate sharp detail at varying distances
What is Presbyopia
The term for when the lens gets less flexible with age
What does the outer ear do?
Directs sound towards eardrum
What does the middle ear do?
Contains 3 small bones the vibrate the fluid inside the inner ear
What does the Inner ear do?
Receives vibrations and transforms to nerve signals, which are then sent to the brain
What is the Nerve that carries signals to the brain from the ear
The Auditory Nerve
