08 Higher Functions and Perception

Question 1

Detail the two forms of the Cicadian rhythm

Answer 1

1. Free Running
   - 25 hours
   - Not effected by Zeitgerbers
2. Endogenous
   - 24 hours
   - Influenced by Zeitgerbers

Question 2

What has the biggest impact on the Cicadian Rhythm?

Answer 2

Body temperature - Higher body temperature, harder to sleep

Question 3

At what time is body temperature at its lowest?

Answer 3

Between 5am and 6am

Question 4

Detail the methods of measuring brain activity:

Answer 4

• Electroencephalogram (EEG): Measures brain waves
• Electrooculogram (EOG): Measures eye movement
• Electromyogram (EMG): Measures muscle tension

Question 5

Detail the stages of the Sleep cycle

Answer 5

1st stage: light sleep/drozey - transition between being awake and asleep

2nd stage: light sleep with fast EEG waves - 50% of sleep

3rd/4th stage: light sleep - muscles are relaxed and unmoving

5th stage: REM sleep - rapid eye movement, only stage with dreams

Question 6

Name and describe the 2 main types of sleep

Answer 6

• Orthodox sleep: comprises of stages 1-4, where muscle and cell damage is repaired
• Paradoxical sleep: comprises of stage 5 (R.E.M.), where memory is strengthened and organised

Question 7

What is the rebound effect?

Answer 7

Where the brain decides how much orthodox or paradoxical sleep is required.

Someone doing lots of physical activity will have more orthodox sleep and someone who is doing a lot of learning will have more paradoxical sleep

Question 8

How long is it between the first stage 1 and the first R.E.M. Stage?

What happens to the R.E.M. Stages as the sleep cycle progresses?

Answer 8

• 90 mins between first stage 1 and the first R.E.M. Stage

- R.E.M. Stages get progressively longer

Question 9

What are the rules around napping during a flight?

Answer 9

Ensure your nap is completed at least 1 hour before descent.

Question 10

What is Jet Lag also known as?

How can it be minimised?

Answer 10

• Aka: Cicadian Dysrhymia or Transmeridean Desycronisation
• To minimise:
• <24 hours: stay on your local time
• > 24 hours: move to the new time
• 24 hours: take a nap on arrival and ensure 8 hours sleep before duty time

Question 11

When are we said to be situationally aware?

Answer 11

When Reality = Perception then we are situationally aware

Question 12

What are the 2 stages of Perception and what is it called when using both at the same time?

Answer 12

• Bottom Up / Data Driven: Information from the sensors is transferred up to the brain
• Top Down / Conceptually Driven: Information is compared to past experiences and knowledge
• Jointly this is called Interactive Processing

Question 13

What are the 5 laws of the Gastalt model?

Answer 13

• Continuity
• Periodic / Closure
• Proximity
• Similarities
• Symmetry

Question 14

What is Visual Constancy?

Answer 14

Perceive that an object is remaining stable even though the image on the retina suggests that it is changing

Question 15

What is Size Constancy?

Answer 15

Recognise that an object remains the same size even though the image on the retina suggests it is getting smaller or bigger

Question 16

What is shape Constancy?

Answer 16

Recognise that an objects shape is not changing even though the angle to to image that is falling on the retina suggests it is changing

Question 17

What is Colour and Brightness Constancy?

Answer 17

Perceive that an object is maintaining it’s colour and brightness in relation to it’s surroundings despite actual light levels changing

Question 18

Describe what Perceptual Set (Expectancy) is and what are the ways it is used?

Answer 18

• Often do not perceive what is actually happening but what we expect to happen
• This is called our expectation
• Very resistant to change
• 2 ways it is used:
• To select relevant information
• To interpret information

Question 19

At what rate do Zeitgebers help resynchronise the Cicadian rhythm?

Answer 19

Zeitgebers resynchronise at an average rate of 1.5 hours per day.