Lesson 1: Methods for studying consciousness

Objectives

• Outline limitations to subjective measures to states of consciousness• Describe and evaluate the methods used to study the level of alertness in normal

waking consciousness and the stages of sleep: measurement of physiological responses including;

          – electroencephalograph (EEG)          - electromyograph (EMG)          – electrooculargraph (EOG)          – heart rate (ECG)          – body temperature          – galvanic skin response (GSR)

Exam Question

Question 3

Two boys, Jason and Eric, were playing football at school. Jason fell to the ground and hit his head. After the fall, Jason was able to speak but seemed confused. Eric wanted to determine whether Jason was experiencing an altered state of consciousness.

a. Describe one characteristic of an altered state of consciousness. How could Eric use this to determine Jason’s state of consciousness?

2 marks

2012 VCAA Exam

Answer

Assessor’s Report 2012

Psychological construct

A phenomena that is believed to exist but cannot be directly measured

We cannot directly measure consciousness

Instead using a range of other measures we can hypothesise about what states of consciousness might be experienced

Electroencephalograph (EEG)

The EEG is a device that detects, amplifies and and records electrical activity in the brain in the form of brainwaves.

Electrodes are attached to the surface of the scalp and the activity of the brain is measuredBrainwaves can indicate an altered state of consciousness.

EOGAn electro-oculargram (EOG) detects, amplifies and records electrical activity of the muscles near the eye.

A high level of electrical activity indicates REM sleep. A low level of electrical activity indicates NREM sleep.

EMGEMG (electromyograph) detects, amplifies and records electrical activity of the muscles in the body.

Very little or no activity indicates REM sleep. An increase in activity indicates NREM sleep.

Electrocardiograph (ECG)

A device that detects, amplifies, and records electrical activity of the heart.

In ASC heart rate can vary. For example, with the use of stimulants, the heart rate increase. In other ASC such as meditation heart rate can decrease.

Galvanic Skin Response (GSR)

A device that detects, amplifies and records the electrical conductivity of the skin.

As the skin becomes moist its electrical conductivity increases

GSR may increase or decrease from normal level when an individual’s arousal is heightened or reduced, as in an altered sate of consciousness.

Thermometer

Measures Body Temperature

Body temperature may increase or decrease from normal level, indicative of an altered state of consciousness. For example, in sleep body temp gradually drops when drifting off into deep sleep

Video Camera

Very little, or no body movement indicates REM sleep. An increase in movement indicates NREM sleep.

Monitor and record externally observable (or audio) physiological responses durning sleep