9.2

Question 1

What is the cornea?

Answer 1

A clear window at the front of the eye which allows light to enter.

Question 2

What is special about the shape of the cornea?

Answer 2

Its shape allows it to function as a fixed focusing device. Responsible for 70-80% of the total focusing ability of the eye.

Question 3

What are the eye and the pupil?

Answer 3

The size of the iris can vary to control the amount of light that enters the eye.

The pupil is the dark area at the centre.

Question 4

What is the lens and why is it important?

Answer 4

It adjusts the level of focus.

Question 5

When is the lens thickest and thinnest.

Answer 5

The lens is thickest when looking at a near object.

It is flattened when looking at a far object.

Question 6

What effects accommodation (the lens)

Answer 6

Age and fatigue.

Question 7

What is the retina.

Answer 7

A complex layer of nerve cells at the back of the eye connected to the optical nerve.

Contains two types of light sensitive cells: cones and Rods.

Question 8

What are cones and how are they different from Rods?

Answer 8

Cones function in good light.
Cones can detect fine detail.

Question 9

Rods.

Answer 9

Rods cannot detect colour.
Good at detecting movement in peripheral vision.
Cones are in the centre of the retina and rods are in the peripherals.

Question 10

The fovea?

Answer 10

A small depression at the centre of the retina that is rés poi le for central vision

Question 11

What does visual acuity mean?

Answer 11

The ability to discriminate sharp detail at varying details.

Question 12

What is hypermetropia?

Answer 12

Long sightedness.

Shorter than normal eyeball
Lens is shorter than normal.

Objects nearby will appear blurred

Question 13

What type of lens is used to correct hypermetropia?

Answer 13

Convex lens.

Question 14

What is myopia?

Answer 14

Short-sightedness.

Eyeball is longer than normal.

Image is formed in front f the retina.

Distant objects will appear blurred.

Question 15

What are other forms of visual problems?

Answer 15

Cataracts - clouding of lens (age related)

Astigmatism - misshapen cornea

Glaucoma - a build up in pressure of the fluid

Migraine - severe headaches, distort vision.

Presbyopia - loss of lens flexibility (age related)

Fatigue

Question 16

Influence of foreign substances on vision.
(Drugs)

Answer 16

Reduces supply of oxygen to eye which can affect the sensitivity of the rods.

Question 17

How long does it take foe cones and rods to adjust to changing lighting conditions.

Answer 17

7 minutes for cones

30 minutes for rods

Question 18

What is colour blindness called

Answer 18

Colour vision deficiency

Question 19

What % of people are effected by colour vision deficiency

Answer 19

8%of men

0.5% of women

Question 20

Can age affect colour vision?

Answer 20

Yes due to yellowing of the lens.

Question 21

CAP 563 Leaflet H-60

Answer 21

Use of glasses or contact lenses is suitable if prescribed for an engineer

Question 22

What are the three divisions of the ear

Answer 22

Outer

Middle

Inner

Question 23

Outer ear

Answer 23

The part of the ear that directs the sound along the auditory canal and into the eardrum.

Question 24

Middle ear

Answer 24

Sits in the eardrum, transmits vibrations.

Made of three small bones called hammer, anvil, stirrup.

Question 25

Inner ear

Answer 25

Filled with fluid. Connected to the cochlea which contain hair like cells which react to the movement of the fluid and send of neural responses

Question 26

What are aural reflex muscles.

Answer 26

Can reduce loud noises by 20db. No protection to sudden explosive noises.

Question 27

What range of frequency can a young person typically hear

Answer 27

20 - 20,000 Hz Sensitivity peaks at 3000, Hz

Question 28

Impact of noie on performance

Answer 28

Annoying others. Interfering with communications Causing fatigue and effecting concentration Damage hearing.

Question 29

What are regulations related to noise and hearing.

Answer 29

Employers must provide hearing protection if needed. Employees have legal right to work without exposure to dangerous noise levels.

Question 30

Two types of hearing protection, and how much protection the provide.

Answer 30

Ear plugs, ear defenders. Noise levels are reduced by 20dB and 40dB respectively

Question 31

Signs of early hearing loss.

Answer 31

Conversations become difficult or impossible. You find it difficult to process sounds like “d” “t” Permanent tinnitus.

Question 32

Noise dose.

Answer 32

Any sound over 80dB over an 8 hour period Any noise over 115 for even short period of time.

Question 33

What is the process of information processing

Answer 33

Receiving information through the senses Analysing information Deriving meaning from the information Storing information.

Question 34

Iconic memory

Answer 34

Provides a smooth stream of visual information to the brain which can be extracted over an extended period of time in the visual short term memory.

Question 35

Presbycusis

Answer 35

Hearing loss with age

Question 36

Echoic memory

Answer 36

Registers sound, once a sound Is heard it is stored in the echoic memory where it can be processed and understood.

Question 37

What are the forms of attention.

Answer 37

Selective attention Divided attention Focussed attention Sustained attention

Question 38

What is “attention”

Answer 38

The brain function that alllocates cognitive processing resources to focus on information or stimuli.

Question 39

Selective attention.

Answer 39

When a person is monitoring several sources of input but focuses on the source that seems ore important

Question 40

Divided attention

Answer 40

Divided attention is common in most work situations, where people are required to do more than one thing at a time

Question 41

Focussed attention

Answer 41

Simply channeling your attention towards a single source and avoiding distraction.

Question 42

Sustained attention.

Answer 42

Is the ability to maintain concentration and remain alert over long periods of time. Usually on one task.

Question 43

What can perception be defined as?

Answer 43

the process of assembling sensations into a usable mental representation of the world

Question 44

What are the three processes of memory

Answer 44

Encoding, storage, retrieval.

Question 45

What is encoding (memory)

Answer 45

The input of information into the brain

Question 46

3 types of memory.

Answer 46

Sensory memory Short-term memory Long-term memory.

Question 47

Sensory memory

Answer 47

Ultra-short memory. Consists of brief sensory events such as sights, sounds and tastes. Very brief, up to a few seconds.

Question 48

Short term memory

Answer 48

Takes information from sensory memory and sometimes connectes that memory to something.

Question 49

Long term memory.

Answer 49

Used to store information no longer in use

Question 50

Two types of long term memory

Answer 50

Semantic memory General facts Episodic memory. Events (Motor programmes Driving a car)

Question 51

What is retrieval

Answer 51

The act of getting information out of memory storage and back into conscious awareness. Decision making is bases on retrieval and past experiences.

Question 52

What is situation awareness

Answer 52

The synthesis of n accurate and up-to-date mental model of ones environment and state, and the ability to use this to make predictions about ones future state.

Question 53

The influence of expectation.

Answer 53

Our perceptual system can reject irregularities, for example when skim reading you wont notice subtle changes in a text that you think you know well.

Question 54

What is claustrophobia

Answer 54

Fear of enclosed spaces.

Question 55

What is acrophobia

Answer 55

Fear of heights