Summary Introductory Psychology I: Chapters 5-6 Review

PSYCH 1003
10/30/25
VARIATIONS IN CONSCIOUSNESS: lecture notes.


Consciousness – Personal Awareness:
 Consciousness means being aware of yourself and your surroundings
 It includes awareness of:
 Internal things (like your heartbeat, hunger, or thoughts)
 External things (like the professor talking or sounds around you)
 Main theories of awareness:
 William James described consciousness as a continuous stream of thoughts
that constantly shift and flow
 Sigmund Freud proposed the existence of an unconscious mind, containing
hidden memories, desires, and feelings that influence behaviour even though
we are not aware of them
 Levels and state of consciousness:
 Normal waking state: clear awareness of self and surroundings
 Altered states of consciousness:
 Sleep and dreams
 Hypnosis
 Meditation
 Drug-induced states
 Research and applications:
 Sleep and dream research explores how consciousness changes across sleep
stages
 During surgery, some people display partial awareness even under anaesthesia;
they may register words spoken by the surgical team but feel no pain


A Physiological Index of Consciousness:
 EEG: a test used to monitor the brain’s electrical activity by recording brain wave
patterns
 Brain wave characteristics:
 Amplitude: the height of the brain wave, showing the strength and activity
 Frequency: the number of brain wave cycles per second, measured in cycles
per second (cps)
 Types of brain waves:
 Beta (13-24 cps): present when awake and alert
 Alpha (8-12 cps): appear when relaxed but still awake
 Theta (4-7 cps): occur during light sleep or drowsiness
 Delta (below 4 cps): seen in deep sleep, also called slow-wave sleep

, Biological Rhythms and Sleep:
 Biological rhythms are regular sleep cycles in the body that influence behaviours and
functions such as sleep, body temperature, and hormone release
 Circadian Rhythms (24-hour biological cycles):
 Control patterns like the sleep-wake cycle, body temperature, and alertness
 E.g., body temperature rises in the morning to help us wake up
 Physiological Pathway of the Biological Clock:
 Light levels are detective by the retina
 The signal travels to the suprachiasmatic nucleus (SCN) in the hypothalamus
 The SCN sends messages to the pineal gland
 The pineal gland adjusts secretion of melatonin, a hormone that regulates sleep
 Key researchers:
 Mistteberger and Harrington: suggested that humans have an internal
biological pacemaker controlling rhythmic activity
 Russak (Dalhousie University): proposed that the body contains multiple
internal clocks working together to manage different biological processes


Effects of Jet Lag on Sleep:
 Jet lag occurs when travel across time zones disrupts the body’s natural seep-wake
cycle (circadian rhythm).
 Main effects:
 Causes fatigue, irritability, and difficulty sleeping
 Travelling east results in more sever disruption because the body must adjust
to an earlier time
 Travelling west causes less disruption since the body adjusts more easily to a
later time
 Sleep and energy regulation:
 Most mammals experience REM sleep, an active stage of sleep important for
brain recovery
 During REM sleep, energy consumption drops by 30 percent
 This stage also helps clear toxins, including beta-amyloid, which can build up
in the brain




Sleep/Waking Research:
 Sleep research examines how the body and brain function during different stages of
wakefulness and sleep
 Instruments used: