Human Information Processing

Question 1

Guidelines in Perception for Human Factors (3)

Answer 1

1. maximize bottom-up processing
2. maximize automaticity and by using familiar perceptual representation
3. maximize top down processing when bottom up processing might be poor

Question 2

examples of maximizing bottom- up processing

Answer 2

high visibility, legibility, audibility

–> prevent confusion due to similar message sets

Question 3

examples of how to maximize automaticity

Answer 3

• use familiar perceptual representation

- familiar fonts, language, meaningful icons, symbols

Question 4

strategies for maximizing top down processing when bottom up processing may be poor

Answer 4

• maximize discriminating features
• create context
• exploit redundancy: both visual and auditory
• use smaller vocab
• be wary of possible perceptual errors under degraded perceptual conditions (night time, foggy etc)

Question 5

• Understanding a situation, achieved through perception and augmented by cognitive transformations will trigger the selection of a
• The selection of a response will be followed by the execution (requiring motor effort – which has its own qualities for success)

Answer 5

response, execution

Question 6

what is signal detection theory and what are the 2 challenges and 2 responses

Answer 6

2 discrete states of the world that are not easily discriminable

• challenges: signal and noise
• 2 responses: yes (signal present), no (signal not present)
• sometimes false alarms and misses will occur

Question 7

why confusion with signal detection theory

Answer 7

• neural noise, thresholds
• noise int he environment
• absolute sensory threshold

Question 8

there are different thresholds for different levels of info processing (4) thresholds

Answer 8

• physiological threshold: stimuli is picked up by sensory organs
• detection threshold: something is there (movement, light, sound)
• identification threshold: see features of stimuli (shape, colour, etc)
• recognition threshold: conceptual categorization (name it)

Question 9

what is important about the signal to noise ration with neural activity in regards to signal processing theory

Answer 9

it has to be high enough to cross the threshold

Question 10

what do we set to assist in our decision making regarding responses and noise int he environment

Answer 10

response criteria

Question 11

what are we better at identifying correctly: if the signal is there vs if the signal is not there

Answer 11

true hit rather than correct rejection

Question 12

what is d’ (D prime)

Answer 12

the sensitivity of the signal detection system

Question 13

what does a large d’ imply? and what does a small d’ imply?

Answer 13

• large implies high sensitivity, a greater difference between response means, easily to detect signal (less overlap)
• small implies low sensitivity, a smaller difference between response means difficult to detect signal

Question 14

response bias depends on (3)

Answer 14

culture, instructions, experience

Question 15

when are we prone to say “yes there is a signal”

Answer 15

less probability of a miss, higher probability of hit

but higher probability of false alarm or lower prob of correct rejection

Question 16

when are we prone to say “no there is no signal”

Answer 16

higher prob of miss, lower prob of hit , lower prob of false alarm, higher prob of correct rejection

Question 17

When would you want to instruct individuals’ to be more liberal or more conservative?

Answer 17

i’m not sure i get this …

Question 18

Signal Detection performance decreases over time, with fatigue

Answer 18

vigilance decrement
- alertness, ability to pay attention over a period of time –  Prolonged monitoring leads to poorer performance after 30 min –  Performance also decreases if signal does not happen very often •  Fire alarm drills •  Evacuation simulations

Question 19

ways to avoid vigilance decrement

Answer 19

Shorter shifts •  Training and experience •  Memory Aids •  Feedback with alarms, signals, controls •  Remove noise and extraneous stimuli (increase signal to noise)