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Flashcards in The Visual System Deck (41):
1

Name the major components of the human eye

  • Cornea
  • Iris
  • Pupil
  • Lens
  • Retina

2

The _________ is the transparent protective tissue located over the front of the eye

Cornea

3

Iris

Round pigmented membrane that adjusts the amount of lights that enters the eye

4

The _______ is the opening in the center of the iris. It allowa light to enter the eye.

Pupil

5

The _______ is a transparent, biconvex membrane that directs light rays entering the pupil upon the retina.

Lens

6

Retina

Thin multi-layered membrane which covers most of the posterior compartment of the eye, contains the photoreceptors

7

What two types of photoreceptor cells are located in the retina?

Cones and Rods

8

Where are Cones located within the retina

Located in Fovea Centralis and parafovea region

9

What are the functions/qualities of Cone cells?

Respond selectively to colors, sharp detals, allows for daytime vision.

10

Where are Rods located within the retina

Located in peripheral region and parafovea region

11

What are the functions/qualities of Rod cells?

very sensitive to low light levels, allows for night vision, poor acuity; detects movement, and edges/lines. Not color sensitive, shades of gray/"purple"

12

Where is the day blind spot and how many degrees does it cover?

Located in the optic disk because it contains no receptor cells (also blind at night).

Covers 5.5 to 7.5 degrees

13

Where is the Night blind spot and how many degrees does it cover?

Located in the Fovea Centralis area because it contains no Rods.

Covers 5 to 10 degrees of the field of vision.

14

Astigmatism

Unequal curvature or irregularities in the cornea or lens that create multiple focal points in the anterior chamber

15

Myopia

nearsightedness; far objects are blurry

16

Hyperopia

farsightedness; near objects are blurry

17

Presbyopia

"old eyes"; due to hardening of the lens that occurs naturally with age; both near and far objects appear blurry; need bi-focals

18

Types of approved corrective eye surgery

PRK, LASIK, and LASEK

19

Types of vision

P.M.S. Photopic Mesopic Scotopic

20

Photopic

Day vision

21

Mesopic

Dusk/dawn; full moon, twilight vision

22

Scotopic

Night vision; partial moon or starlight

23

Which type of vision is considered the most dangerous for Aviation

Mesopic

24

Cues to distance estimation and depth perception (2 types)

Binocular and Monocular

25

Monocular

Visual cues from one eye

26

Binocular

Visual cues from two eyes

27

Which type of cue is more important in aviation (monocular or binocular)

Monocular

28

What is the acronym for the monocular cues for depth perception

G.R.A.M.

29

Expand the acronym G.R.A.M

Geometric Perspective Retinal image size Aerial perspective Motion Parallax

30

Types of Geometric Perspective L.A.V.

Linear Perspective Apparent Foreshortening Vertical position in the field

31

Types of Retinal image size K.I.T.O.

Known size of objects Increasing or decreasing size of objects Terrestrial association Overlapping Contours

32

Types of Aerial Perspective F.L.P.

Fading of colors and shades Loss of textures and detail Position of light source

33

What is the MOst important of the MOnocular cues

MOtion parallax

34

_______ compensates for the night blind spot?

Scanning

35

An unequal curvature of the cornea resulting in the inability of the eye to focus on multiple objects simultaneously in the horizontal and vertical planes is called?

Astigmatism

36

What is the proper name for nearsightedness?

Myopia

37

What is the proper name for farsigthedness?

Hyperopia

38

This occurs with the aging process and results in the hardening of the lens?

Presbyopia

39

Vitamin A is required for the production of?

Rhodopsin

40

The apparent relativ motion of stationary objects as viewed by a moving observer is?

Motion Parralax

41

Average time to dark adapt is ____ - _____ minutes for a well rested aviator

35 - 40