Unit 3/Part 3: Physiological Measurements Of Consciousness Flashcards
List the four main brainwaves and their characteristics.
Beta - high frequency, low amplitude. Occurs during REM sleep (dreaming) as well as being awake and alert.
Alpha - high frequency but lower than beta, low frequency but higher than beta. Occurs when drowsy, daydreaming or during meditation.
Theta - medium frequency, mixed amplitude. Occurs during light sleep (NREM 1&2) *remember Thea likes M&M’s
Delta - low frequency, high amplitude. Occurs during deepest sleep (NREM 3&4)
REMEMBER B.A.T.D
List and explain the 3 other brainwave patterns.
K-complexes: sharp rise and fall of amplitude (high bursts of amplitude) lasting for about 2 seconds. Associated with stage 2 NREM sleep.
Sleep spindles: periodic bursts of rapid frequency, which are indicative of stage 2 NREM sleep.
Sawtooth waves: random fast waves that are slightly bigger than alpha waves. They resemble waves for being awake but occur among the beta-like waves during REM sleep. Medium to high amplitude. Sawtooth waves are associated with dreaming.
When we are lying in bed, feeling drowsy but still awake, we are likely to exhibit what type of brainwaves?
Alpha (high frequency but lower than beta and low amplitude but higher than beta)
Sawtooth brainwaves are associated with what stage of sleep?
REM sleep
How is the EOG useful?
It’s useful in measuring sleep because it determines which phase of sleep an individual is in judging by eye movement.
How is the Electromyograph useful?
Measuring changes in electrical activity in the muscles that accompany changes on states of consciousness. It can also be useful in determining whether a person is awake or asleep, and if asleep, which one of the two main types of sleep (REM or NREM).
What is a polysomnogram?
A continuously moving chart that displays data collected from the EEG, EOG, EMG and other devices. It’s useful in measuring sleep as it enables a researcher to compare corresponding data and make informed decisions about the state of consciousness a person is in and indicates REM or NREM stages.
Describe an ECG.
An electrocardiograph is a device that detects, amplifies and records electrical activity of the heart muscles. Heart rate is measured in beats per minute.
Name 2 states in which heart rate increases and 2 in which it decreases.
Increases: strong emotions, physical activity and stimulant drug e.g. Caffeine
Decreases: drowsiness and meditating
When is our body temperature lowest in a 24-hour period?
Body temperature tends to peak mid-afternoon and reach lowest point in early hours of the morning (1am-4am).
What happens to the GSR when we sweat?
Strong emotions and or physical activity during NWC increases GSR, whereas it decreases when relaxed and in cool environment. In some ASC, GSR will increase (alcohol induced state) and decrease (meditation). When sweat decreases electrical conductivity (current passes slower) and resistance increases and vice versa.
What sort of data is normally gathered in a sleep lab?
Video monitoring and self reports as well as data from physiological measurement devices.
Name one advantage and disadvantage of a sleep lab.
Advantage: allows brainwave activity and other physiological measures to be monitored in a controlled environment.
Disadvantage: participant may feel uncomfortable and face difficulty falling asleep due to unfamiliar environment as well as disrupted sleep.
Name one advantage and disadvantage of video monitoring.
Advantage: provide insight into how we behave in different states of consciousness. Researchers can observe participants at any time and give to other researchers to interpret.
Disadvantage: can’t tell us what’s going on inside the body or what the participant is experiencing. Therefore observations may be subjective.
What is a self report?
Statements and answers to questions made by the participants concerning their psychological experience (thoughts, feelings and behaviours). Carried out in number of ways such as questionnaires, diary entries and interviews.
Name an advantage and disadvantage of a self report.
Advantage: captures persons psychological experience and indicates whether or not person is in NWC or ASC.
Disadvantage: participants may forget info or may not know how to describe experience.
What percentage of our life do we spend in the ASC we call sleep?
33%
Why is sleep considered a circadian rhythm?
Because the sleep/wake cycle is an example of a biological rhythm that occurs approximately once every 24 hours.
What are the two different types of sleep?
NREM and REM
Explain NREM
NREM stands for non-rapid eye movement, which is divided into four states of sleep. Stages are determined by brainwave patterns.
Explain REM
Rapid eye movement stage of sleep, the amount of time spent in REM sleep increase and NREM decreases as the night progresses.
What is the NREM/REM cycle an example of?
An ultradian rhythm, a biological rhythm that’s shorter than 24 hours.
How long does REM/NREM cycle last?
90 minutes on average.
What brainwaves occur when we’re awake?
Beta waves; short (low amplitude) and fast (high frequency)
What percentage of time is spent in NREM sleep?
80%
Describe what happens in the twilight stage of sleep, known as the hypnagogic state.
During this state (transition from being awake to falling asleep) we may experience hallucinatory images, such as flashes of light and vivid images.