6.3 Measurement of physiological responses associated with sleep

Question 1

Define EEG (Electroencephalography)

Answer 1

A method of studying brain wave patterns by recording the electrical activity of the brain. Records brain waves by receiving signals from neurons in brain.

Question 2

Define Beta pattern

Answer 2

A beta brain wave pattern is associated with alertness and intensive mental activity during normal waking consciousness. Beta waves are also present when dreaming during a period of rapid eye movement sleep.

Question 3

Define Alpha pattern

Answer 3

We are awake and alert but mentally and physically relaxed and internally focused, the EEG shows a predominantly alpha brain wave pattern. For example, if you complete a mentally active task and sit down to rest and calmly reflect on what you did, your brain waves will be mostly alpha, especially if you close your eyes.

Question 4

Define Theta pattern

Answer 4

A theta brain wave pattern is most commonly produced when we are very drowsy, such as when falling asleep or just before waking. They may also be produce

Question 5

Define Delta pattern

Answer 5

Delta waves are most commonly associated with deep, dreamless sleep or unconsciousness.

Question 6

Define Electromyography (EMG)

Answer 6

A method of studying the electrical activity of muscles during sleep. Shows that our muscles progressively relax as we sleep.

Question 7

Define Electro-oculography (EOG)

Answer 7

A method of measuring eye movements or eye positions during sleep. Shows that during REM sleep we have rapid eye movement that aligns with brain patterns.

Question 8

Define sleep diary

Answer 8

A self-report record of an individual’s sleep and waking time activities. However its subjective as it is exposed to bias.

Question 9

Define the need for video monitoring

Answer 9

• changes in posture or body position
• amount of ‘tossing and turning’
• sleep-related breathing problems
• what happens when awakening from a nightmare or night terror
• behaviours associated with sleepwalking.

Question 10

Define frequency in relation to brain waves

Answer 10

Number of brain waves per second; a pattern of high frequency activity is faster and therefore has more brain waves per unit of time; a pattern of low-frequency activity is slower, and therefore has fewer brain waves per unit of time

Question 11

Define amplitude in relation to brain waves

Answer 11

Intensity of brain waves measured in microvolts; can be visually judged by the size of the peaks and troughs of the waves from a baseline of zero activity; high-amplitude brain waves have bigger peaks and troughs, while low-amplitude have smaller peaks and troughs