Class13 Consciousness

Consciousness

Chapter 5

Consciousness:a person’s subjective experience of

the world and the mind

Phenomenology:how things seem to the conscious

person

Consciousness

• Problem of other minds: the fundamental difficulty we have in perceiving the consciousness of others– People judge minds according to the

capacity for experience and agency.

Consciousness

• Mind/body problem: the issue of how the mind is related to the brain and the body– Originally proposed by Descartes– Brain activity may precede conscious

activity.• Where does that leave “free will”?

Figure 5.3The Timing of Conscious Will

http://www.youtube.com/watch?v=9_ZG_ewoOI0 (about 51:00-56:00)

The Nature of Consciousness

Consciousness has four basic

properties

Intentionality:the quality of being directed toward an

objectUnity:

resistance to division; divided

attention leads to interference

Transience:the tendency to

change

Cocktail party phenomenon: a phenomenon in which people tune in one message while they filter out others nearby

Selectivity:the capacity to include some objects but not

others

The Nature of Consciousness

• Transience – the tendency of consciousness to change – E.g., the Necker cube– And…

Levels of Consciousness

• Minimal consciousness: – a low-level kind of sensory awareness and

responsiveness that occurs when the mind inputs sensations and may output behavior

• Full consciousness: – consciousness in which you know and are able to

report your mental state

Self-Consciousness

• Self-consciousness: – a distinct level of consciousness in which

the person’s attention is drawn to the self as an object

http://www.youtube.com/watch?v=W-pc_M2qI74&feature=related

• People can report on their conscious experiences by thinking aloud or using the experience sampling technique.

• Studies show that consciousness is dominated by current concerns.

Conscious Contents

Hot Science: The Mind Wanders

• We may be unaware of our minds wandering.– Similar to under the influence of alcohol– Effects of driving while ‘wandering’ and drinking

while driving – dangerous!

• Our minds most often wander when we are engaged in automated, repetitive tasks or in difficult/complex tasks.

• 2,250 participants, ranging from age 18 to 88• via an iPhone app all kept track of

– how happy they were– what they were currently doing– whether they were thinking about their current

activity or about something else that was pleasant, neutral, or unpleasant

• This is the experience sampling method (ESM)

Present mind, happy mind?Killingsworth and Gilbert (2010)

http://www.sciencedaily.com/releases/2010/11/101111141759.htm

Results

• Minds were wandering 46.9% of the time, on average– at least 30% during every activity except making

love • Mind-wandering status accounted for about

10.8% of their happiness– Time-lag analyses suggested that mind-wandering

was generally the cause, not the consequence, of unhappiness

Conscious Contents

• Mental control: the attempt to change conscious states of mind

• For instance,– Thought suppression: the conscious

avoidance of a thought

Do not think of a pink elephant!

Conscious ContentsRebound effect of thought suppression:

– the tendency of a thought to return to consciousness with greater frequency following suppression

The Unconscious Mind

Unconscious processing may help in complex decision making.

Freudian Unconscious Dynamic unconscious: an

active system encompassing a lifetime of hidden memories, the person’s deepest instincts and desires, and the person’s inner struggle to control these forces; described by Freud

Repression: a mental process that removes unacceptable thoughts and memories from consciousness

Modern Unconscious Cognitive unconscious: the

mental processes that give rise to a person’s thoughts, choices, emotions, and behavior even though they are not experienced by the persono Subliminal perception: a

thought or behavior that is influenced by stimuli that a person cannot consciously report perceiving; controversial

Freud’s Unconscious

• Dynamic unconscious: – an active system encompassing s lifetime of

hidden memories, the person’s deepest instincts and desires, and the person’s inner struggle to control these forces; described by Freud

• Repression: – a mental process that removes unacceptable

thoughts and memories from consciousness

http://www.youtube.com/watch?v=AUB85lSj4pM&feature=relatedhttp://www.youtube.com/watch?v=T2eyP6iY5Do&feature=related

The Modern Unconscious

• Cognitive unconscious: – the mental processes that give rise to a

person’s thoughts, choices, emotions, and behavior even thought they are not experienced by the person

The Modern UnconsciousSubliminal perception:

– a thought or behavior that is influenced by stimuli that a person cannot consciously report perceiving

– controversial!

Sleep & Dreams

Sleep and Dreaming

• Altered state of consciousness: – forms of experience that are different from the

normal subjective experience of the world and the mind

• Circadian rhythm: – a naturally occurring 24-hour cycle

Sleep Cycle

• Brain shows EEG changes in beta, alpha waves, theta, and delta waves

• Five stages of sleep: • stages 1 – 4• REM sleep

Sleep Cycle• REM sleep: a stage of sleep characterized by

rapid eye movements and a high level of brain activity– Electro-oculograph (EOG): an instrument that

measures eye movements– Dreaming occurs most often here– Body is immobilized

Sleep Needs and Deprivation

• How much sleep do people need?– across our lifetime, we get about 1 hour of sleep for

every 2 awake.– 7-7.5 hours for an adult (more for children, less for

elderly)

Sleep Needs and Deprivation

Sleep deprivation leads to reduced mental acuity & reaction time, increasing irritability, depression, & risk of accidents– disruption of REM leads to memory problems &

extreme aggression– disruption of stages 3 & 4 leads to tiredness &

hypersensitivity to muscle & bone pain

PBS Nova on Sleep: http://video.pbs.org/video/1233237984 (4:00-12:49)

Dreams

Figure 5.13Brain Activation and Deactivation During REM Sleep

fMRI scans of brains during dreaming show brain areas involved in emotion and visual

imagery, but not the prefrontal cortex (planning, self-control, etc.)

Dreams

Dream consciousness1. intense emotions2. illogical thought3. fully formed, meaningful

sensations4. uncritical acceptance5. difficulty remembering

Nightmares– average undergrad has 24 nightmares per year– more in children & after traumatic events

Dreams: Theories

1. Freudian theory:– Manifest content: a dream’s apparent topic or

superficial meaning– Latent content: a dream’s true underlying meaning

2. Activation-synthesis model: – the theory that dreams are produced when the

brain attempts to make sense of activations that occur randomly during sleep

Sleep Disorders

• Insomnia: difficulty in falling asleep or staying asleep• Sleep apnea: the person stops breathing for brief

periods while asleep• Somnambulism (sleepwalking): occurs when the person

arises and walks around during sleep• Narcolepsy: sudden sleep attacks occur in the middle of

waking activities• Sleep paralysis: the experience of waking up unable to

move• Night terrors (sleep terrors): abrupt awakenings with

panic and intense emotional arousal

Drugs

Drugs and Consciousness

• Psychoactive drug: a chemical that influences consciousness or behavior by altering the brain’s chemical message system

• Drug tolerance: the tendency for larger doses of a drug to be required over time to achieve the same effect– Drug withdrawal symptoms include physical

dependence and psychological dependence.– Drug addiction has different definitions.

Table 5.2Dangers of Drugs

http://www.youtube.com/watch?v=5LwEQdB4fJM (7:20)

Depressants• Depressants: reduce the activity of the CNS• Alcohol is the ‘king’ of depressants.

– Expectancy theory: the idea that alcohol effects can be pronounced by people’s expectations of how alcohol will influence them in particular situations

– Balanced placebo design: a study design in which behavior is observed following the presence or absence of an actual stimulus and also following the presence or absence of a placebo stimulus

– Alcohol myopia: a condition that results when alcohol hampers attention, leading people to respond in simple ways to complex situations

Stimulants• Stimulants: excite the CNS, heightening

arousal and activity levels– Types include caffeine, amphetamines, nicotine,

cocaine, modafinil, and ecstacy (MDMA)• Stimulants elicit euphoria and confidence/

motivation (increase DA and NE in brain)

Narcotics

• Narcotics (opiates): highly addictive drugs derived from opium that relieve pain– Types include heroin, morphine, methadone, and

codeine• Drug properties are closely related to the

endorphins.

Hallucinogens• Hallucinogens:

– alter sensation & perception– often cause visual and

auditory hallucinations– includes LSD (or acid),

mescaline, psilocybin, PCP, and ketamine

• Effects are dramatic and unpredictable.

Marijuana

• Marijuana: the leaves and buds of the hemp plant that produces an intoxication that is mildly hallucinogenic

• Drug affects judgment, short-term memory, and motor skills/coordination

• Medicinal uses controversial

The Real World: Drugs and the Regulation of Consciousness.

• War on Drugs– sees drug abuse mostly as a justice problem– much like prohibition– increase in crime & imprisonment

• Harm reduction approach (e.g., the Netherlands)

– e.g., providing methadone to heroin addicts, clean needles to prevent HIV, checking safety of Ecstasy

– sees drug abuse mostly as a medical problem– reduces use & criminality

Hypnosis, Meditation, and Religious Experiences

Hypnosis: Open to Suggestion

• Hypnosis: an altered state of consciousness characterized by suggestibility and the feeling that one’s actions are occurring involuntarily– The essence of hypnosis is in leading people to

expect that certain things will happen that are outside their conscious will

• Susceptibility varies greatly, subject to agreeableness

Hypnosis: Open to Suggestion

Hypnotic effects:– Hypnotic analgesia: the reduction of pain through

hypnosis in people who are susceptible to hypnosis– PET scans show brain activation of hypnotic

hallucination to be similar to real perception.

Meditation

Meditation: the practice of intentional contemplation– Variety of techniques in and outside of religion– Effects include rest, revitalization, and psychological

well-being• Long-term effects controversial• Temporarily altered patterns of brain activation (EEG)

Religious Experiences

Altered states may also occur during religious prayer or worship– Some claim to experience profound or ecstatic

fervor– Brain activation similar in cases of epilepsy.

• Right anterior temporal lobe linked with religious ecstasies