CONSCIOUSNESS
NOTES
,The Puzzle of Consciousness
What is consciousness?
Moment-to-Moment Awareness
o External & Internal Stimuli
Dynamic
o Constantly shifting & changing
Self-reflective
o Central to our sense of self
Subjective & Personal
o Problematic construct
Why do we have consciousness?
Allows us to
o Make sense of stimuli being experienced
Facilitates planning & decision making
o Take control of situations
Override automatic, potentially dangerous behaviours
o Deal with unusual situations & tasks
How do we measure consciousness?
Self-Report Measures
Ask people to describe their inner experiences
Problematic for research
Behavioural Measures
Record performance on special tests
o Glasgow Coma Scale
o The Mirror Test
Physiological Measures
Establish connection between bodily processes & mental states
o Electroencephalograph measures brain activity
,Levels of consciousness
Freudian Viewpoint
Tip of the iceberg= Conscious Level
Cognitive Viewpoint
Conscious & unconscious mental life are complimentary forms of
information processing
o work in harmony
Selective Attention
Focussing awareness on some stimuli while ignoring others
Fundamental component of consciousness
Controlled (conscious/explicit) Processing
Conscious use of attention
Slower & more flexible
o Automatic (unconscious/implicit) Processing
Used in activities performed without awareness / effort
Fast & routine action
Divided Attention
Attending to more than one activity at a time
,Unconscious perception
Visual Agnosia
Inability to recognise objects visually
Blindsight
Occurs when an individual is blind
o But can still respond to stimuli
Priming
Exposure to a stimulus influences responses to subsequent stimuli
o Subliminal stimuli
Emotional Unconscious
Emotional & motivational processes operate unconsciously
o Influences behaviour
Neural bases of consciousness
No single brain region is responsible
Consciousness is a global workspace
o Represents the unified activity of multiple brain areas
Extended Reticular Thalamic Activating System (RAS)
o 1950s – Damage to this system leads to a comatose state
o Present in all vertebrates
Dogs
Lizards
Snakes
o Not present in bees, ants, jellyfish
o Part of brainstem
Generally brainstem is NB for consciousness
,Circadian Rhythms
24-hour biological clock
o Normally regulated by light & dark
Controls
o Body temperature
o Hormones
o Other bodily functions
Regulated by the Suprachiasmatic Nuclei (SCN)
o In hypothalamus
o Obtains information about light through the eye
o SCN Pineal Gland Melatonin
o Active during the day
Reduced melatonin
o Inactive at night
Increased melatonin
Circadian Disruptions
Jet Lag
Acute exposure to circadian desynchronisation
Flying across time zones
o Exposes one to a new light-dark cycle
o Biological clock keeps time
“Official” clock time changes
o Big problem for people who do it often
Symptoms
o Headaches
o Fatigue
o Insomnia
o constipation/diarrhoea
o concentration problems
o mood disturbances
Travelling west is easier
o can adapt by staying up late
Night Shifts
Chronic exposure to circadian desynchronisation
Work in opposition to natural sleep-wake cycle
o May lead to poor quality sleep
o May lead to social disruptions
Can cause
o Fatigue
o Stress
o Accidents
, Seasonal Affective Disorder
Cyclic tendency to become depressed during certain seasons
o Usually autumn & winter
o Throughout rest of year people are mentally healthy
Same symptoms as a depression
o Considered a mood disorder
o Light Therapy used as treatment
First described by someone who moved from “sunny” South Africa to New
York
NOTES
,The Puzzle of Consciousness
What is consciousness?
Moment-to-Moment Awareness
o External & Internal Stimuli
Dynamic
o Constantly shifting & changing
Self-reflective
o Central to our sense of self
Subjective & Personal
o Problematic construct
Why do we have consciousness?
Allows us to
o Make sense of stimuli being experienced
Facilitates planning & decision making
o Take control of situations
Override automatic, potentially dangerous behaviours
o Deal with unusual situations & tasks
How do we measure consciousness?
Self-Report Measures
Ask people to describe their inner experiences
Problematic for research
Behavioural Measures
Record performance on special tests
o Glasgow Coma Scale
o The Mirror Test
Physiological Measures
Establish connection between bodily processes & mental states
o Electroencephalograph measures brain activity
,Levels of consciousness
Freudian Viewpoint
Tip of the iceberg= Conscious Level
Cognitive Viewpoint
Conscious & unconscious mental life are complimentary forms of
information processing
o work in harmony
Selective Attention
Focussing awareness on some stimuli while ignoring others
Fundamental component of consciousness
Controlled (conscious/explicit) Processing
Conscious use of attention
Slower & more flexible
o Automatic (unconscious/implicit) Processing
Used in activities performed without awareness / effort
Fast & routine action
Divided Attention
Attending to more than one activity at a time
,Unconscious perception
Visual Agnosia
Inability to recognise objects visually
Blindsight
Occurs when an individual is blind
o But can still respond to stimuli
Priming
Exposure to a stimulus influences responses to subsequent stimuli
o Subliminal stimuli
Emotional Unconscious
Emotional & motivational processes operate unconsciously
o Influences behaviour
Neural bases of consciousness
No single brain region is responsible
Consciousness is a global workspace
o Represents the unified activity of multiple brain areas
Extended Reticular Thalamic Activating System (RAS)
o 1950s – Damage to this system leads to a comatose state
o Present in all vertebrates
Dogs
Lizards
Snakes
o Not present in bees, ants, jellyfish
o Part of brainstem
Generally brainstem is NB for consciousness
,Circadian Rhythms
24-hour biological clock
o Normally regulated by light & dark
Controls
o Body temperature
o Hormones
o Other bodily functions
Regulated by the Suprachiasmatic Nuclei (SCN)
o In hypothalamus
o Obtains information about light through the eye
o SCN Pineal Gland Melatonin
o Active during the day
Reduced melatonin
o Inactive at night
Increased melatonin
Circadian Disruptions
Jet Lag
Acute exposure to circadian desynchronisation
Flying across time zones
o Exposes one to a new light-dark cycle
o Biological clock keeps time
“Official” clock time changes
o Big problem for people who do it often
Symptoms
o Headaches
o Fatigue
o Insomnia
o constipation/diarrhoea
o concentration problems
o mood disturbances
Travelling west is easier
o can adapt by staying up late
Night Shifts
Chronic exposure to circadian desynchronisation
Work in opposition to natural sleep-wake cycle
o May lead to poor quality sleep
o May lead to social disruptions
Can cause
o Fatigue
o Stress
o Accidents
, Seasonal Affective Disorder
Cyclic tendency to become depressed during certain seasons
o Usually autumn & winter
o Throughout rest of year people are mentally healthy
Same symptoms as a depression
o Considered a mood disorder
o Light Therapy used as treatment
First described by someone who moved from “sunny” South Africa to New
York