Chapter 5 - The eye and vision Flashcards
What parts of the eye are directly associated with vision?
Cornea - Coarse
Lens - Fine focus
Iris - moderate light entering
Retina - the sensor, housing…
Rods - Night vision
Cones - Colour
Optic nerve runs from where to where?
retina to visual cortex
Are rods or cones in the centre of the retina?
cones
What is the name for the central part of the retina?
Fovea
Rods are found in the centre or around the edges of the retina?
Around the edge
What is the phrase used to describe how the ciliary muscle contracts and relaxes to change the shape and focal length of the lens?
Accommodation
When attending to a visual stimulus, the eye focuses light on which part of the retina?
Fovea
What describes the ‘resolution’ of the eye?
visual acuity
If ‘central vision’ is the part of the visual field in the centre and populated by cones, how would you describe the vision around the edge?
Cones – best for central vision
Rods – best for peripheral vision
At night, ______ ______ is degraded and we rely mostly on our rods.
visual acuity
Aside from night vision, what else could degrade visual acuity? (4)
Age
Hypoxia
Life style
Medication / Drugs
At night, does looking off-centre at a dim object help see it?
Apparently so!
The cabin altitude is greater than 5000ft, or you are getting Hypoxic, what vision would you expect to be affected?
Night vision
Time for the eye to adjust from dark to light?
10 seconds
Time for the eye to adjust from light to dark?
Cones – 7 minutes
Rods – 30 minutes
