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:
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:
