Sleep and Dreaming Flashcards
Consciousness
Awareness of objects and events in the external world and of our sensations, mental experience and existence at any given moment.
Normal Waking Consciousness
Awareness of internal states and external surroundings when we are awake and unaffected by sleep, drugs, or other states.
Altered State of Consciousness
Anything that is not normal waking consciousness.
Sleep
A reversible behavioural state of perceptual disengagement from and unresponsiveness to the environment.
Suprachiasmatic Nucleus
Found within the hypothalamus.
Responsible for controlling circadian rhythms. They are sleep wake cycles that occur every 24 hrs.
Detects the amount of light being sent to the brain for processing and influences the amount of melatonin being released into bloodstream.
Main role is to regulate the onset (beginning) of sleep.
Melatonin
Hormone that is produced and secreted in the pineal gland.
Gradually builds up during the day. High levels of melatonin cause sleepiness. Once levels reach a critical level, a person falls asleep. The more light, the less melatonin.
Reticular Activating System
Found in Thalamus.
Regulates cortical arousal. i.e. alertness.
When sleeping, there is a state of low cortical arousal sp the role of the RAS in sleep is to maintain the sleep state.
Influences when we are asleep or awake by restricting the amount of simulation cerebral cortex receives, allows us to stay asleep.
Major parts of RAS = reticular formation and thalamus.
Reticular Formation
Through the brain stem and up into mid brain.
Reducing the stimuli that is sent to cerebral cortex.
Thalamus
Transfer station for information from senses.
Transfers neural information form the reticular formation to cerebral cortex.
Filters sensory information and closes sensory pathways during sleep.
Sleep Research
Takes place in sleep laboratories.
Many devices are used to monitor and record physiological responses of patients studied there.
Electroencephalograph (EEG)
Detects, amplifies and records electrical activity generated by the brain (D.A.R.E). Distinguishable patterns of electrical activity (called brain waves).
Amplitude
Measured in the wave height
Frequency
How close waves are to one another
Electromyograph (EMG)
Detect, amplify and records the electrical activity of muscles.
Shows strength of electrical activity occuring in the muscles, changes in muscle activity and muscle tone.
Information obtained by attaching electrodes to particular muscles and recorded as line graphs.
Most aware to Least Aware waves
Batman Ate The Donut (most to least)
Beta waves
Alpha waves
Theta waves
Delta waves
Beta waves = most aware (e.g. Stage 1 or REM sleep) to Delta waves being heavy sleep (stage 4).
Electro-oculogram (EOG)
Device for measuring eye movements or eye positions by detecting, amplifying and recording electrical activity in eye muscles.
Done through electrodes attached to area of the face surrounding the eyes. Recordings are displayed as line graphs.
Hypnogram
Graph that shows sleep cycles across one night sleep.
x - axis = time/duration of sleep
y - axis = stages of sleep NREM 1-4 + REM
Two types of sleep
- Non Rapid Eye Movement Sleep (Non - REM)
- Rapid Eye Movement Sleep (REM)