Ways of measuring consciousness

Question 1

Electroencephalograph (EEG)

Answer 1

is a device which detects (through the use of electrodes), amplifies and records electrical activity in the brain in the form of brainwaves. It does this by monitoring electrical activity detected on the outside of the skull. Recordings from EEG’s are called electroencephalograms.

Question 2

Electromyograph (EMG)

Answer 2

is a device that detects, amplifies and records electrical activity of the muscles. Electrodes are attached to the skin around the muscles. It indicates a change in muscle activity, muscle tone or muscle tension that occur during different stages of consciousness.

Question 3

Electro-oculargraph (EOG)

Answer 3

is a device that detects electrical activity in the muscles that allow the eyes to move using electrodes placed around the eyes. One set of electrodes measures the right eye and another does the left. The resulting signal is called an electrooculargram, it measures the changes in voltages as the eyes move and rotate in their sockets. It can easily show NREM vs REM sleep.

Question 4

Heart rate

Answer 4

can be measured using a standard heart rate monitor or by using an EMG. The EMG detects, amplifies and records the electrical activity of the heart muscle. Heart rate is measured in beats per minutes (BPM). It rises with more activity. During NREM it is usually regular, while in REM it is irregular.

Question 5

Body temperature

Answer 5

follows a circadian rhythm and varies regularly over a 24 hour period. Usually is measured by recording the temperature on the skin of the fingers. It tends to peak in mid-afternoon and reach its lowest point in the early hours of the morning. Drops and rises in temperature can lead to drowsiness.

Question 6

Galvanic Skin Response (GSR)

Answer 6

is a physiological response that indicates the electroconductivity of the skin. As the skin becomes more moist the conductivity increases. In some ASC’s it will increase (stimulants) but in others will decrease (meditation).

Question 7

Beta waves

Answer 7

• high frequency + low amplitude - associated with NWC and focused attention

Question 8

Alpha waves

Answer 8

• high frequency (slower than beta) and low amplitude - relaxed, drowsy, meditative state

Question 9

Theta waves

Answer 9

• Medium frequency (slower than alpha + beta) & a mix of high & low amplitude waves. - Associated with early stages of sleep.

Question 10

Delta waves

Answer 10

• Lowest frequency & highest amplitude - Associated with deepest stages of sleep - Slowest of the brain waves

Question 11

Sleep laboratory

Answer 11

are used by researchers to create an environment for participants to be tested in while they are hooked up to the various machines.

Question 12

Video monitoring

Answer 12

is usually used in conjunction with sleep laboratories and uses infared cameras to capture footage of the sleeping participant without disturbing them. Limitations include only being able to see the footage from one angle and the behaviours have to be interpreted by the researcher meaning observations can become subjective.

Question 13

Self reports

Answer 13

are also used with sleep laboratories and are statements and answers to questions made by the researchers and answered by the participant concerning their thoughts and feelings. They can be in the form of a questionnaire, diary entries and interviews. They are extremely valuable in terms of what the participant is experiencing but are limited by participant’s potentially not telling the truth, not remembering and what they may have left out.

Question 14

Overall ways of studying consciousness

Answer 14