Psychology Chapter 9: Consciousness

Course Information

• Subject: Introduction to Psychology
• Subject Code: FAMG 1023
• Lecturer: Atiqah Jani (K.B., P.A.)
• Faculty: Centre for Foundation, Languages & General Studies

Chapter 9: Consciousness

Learning Outcomes

• Explain why early psychologists abandoned the study of consciousness and why current research is possible.
• List methods used to present stimuli while preventing conscious perception.
• Describe how consciously perceived stimuli activate brain areas differently from stimuli not consciously perceived.
• Provide evidence of unconscious brain processing.
• Discuss cases where individuals in a vegetative state showed evidence of consciousness.
• Describe and evaluate evidence showing brain activity for a movement begins before the conscious decision to act.

Measuring Consciousness

• Operational definition: If a person consciously perceives one stimulus and not another, they were conscious of the first stimulus and not the second.
• Methods of measuring brain activity:
  • Masking: Presenting a stimulus with an interfering pattern to prevent consciousness.
  • Flash suppression: Blocking consciousness of a stationary stimulus by surrounding it with rapidly flashing items.
  • Binocular rivalry: Alternation between seeing a pattern in the left retina and the pattern in the right retina.
• Limited research questions.

Brain Activity, Conscious or Unconscious

• Conscious stimulus activation causes stronger neural activity that reverberates through brain areas.
• This magnified activity inhibits responses to competing stimuli.

Unconscious Processing of a Suppressed Stimulus

• The brain processes stimuli without consciousness, evaluating their importance.
• Unconscious processes are vital for cognition.

Consciousness as an All-or-None Phenomenon

• Consciousness appears as an all-or-none process.
• Either brain activity spreads strongly or not.

Consciousness as a Construction

• Conscious experience of a stimulus occurs slightly after the stimulus, not simultaneously.

Can We Use Brain Measurements to Infer Consciousness?

• Physicians define different gradations of brain activity, linking them to arousal, responsiveness, and consciousness.
  • Brain death: Absence of brain activity and response.
  • Coma: Steady, low-level brain activity with no response.
  • Vegetative state: Limited responsiveness to stimuli.
  • Minimally conscious state: Brief purposeful actions and speech comprehension.
• Brain scans can suggest consciousness in unresponsive patients.

Consciousness and Action

• Brain scans reveal brain activity responsible for movement begins before the reported conscious decision time.

How Well Can We Measure the Time of a Conscious Decision?

• Research challenges the accuracy of self-reported decision times.
• Voluntary decisions are gradual, not sudden.

What Is the Purpose of Consciousness?

• A possible function of consciousness is preparing for future actions in similar situations.

Sleep and Dreams

Circadian Rhythms

• Circadian rhythm: A 24-hour cycle of activity and inactivity regulated by the body.
• The rising and setting of the sun reset the circadian rhythm.
• Circadian rhythms control more than just sleep/wake cycles (e.g., hunger, thirst, alertness, body temperature).
• Circadian rhythms vary between people (morning and evening types).

Morning People and Evening People

• Some people quickly reach their peak alertness early in the day, while others do so later.
• Most young adults are evening or intermediate types; most over 65 are morning types.
• People generally adjust more easily to traveling west than east.
• Graveyard shifts are harder to adjust to.

Brain Mechanisms of Circadian Rhythms

• The suprachiasmatic nucleus (SCN) in the brain is responsible for generating the circadian rhythm.
• Sunlight partially resets the circadian rhythm.
• The SCN regulates melatonin secretion (by the pineal gland) which impacts the circadian rhythm.

Why We Sleep

• Sleep conserves energy and facilitates learning and memory.
• Sleep-deprived people struggle with attention.

Stages of Sleep

• Rapid eye movement (REM) sleep: Characterized by rapid eye movements, high brain activity, and deep muscle relaxation. Dreams are common during this stage, though not limited to it.

Insomnia

• Insomnia: Difficulty sleeping enough to feel rested.
• Insomnia is caused by various factors including noise, worries, indigestion, uncomfortable temperatures, alcohol/caffeine use or medical/psychological disorders.

Sleep Apnea/Narcolepsy

• Sleep apnea: Condition where breathing stops for a minute or more during sleep causing the sufferer to wake up gasping for breath. This is common in overweight middle-aged men with narrow breathing passages.
• Narcolepsy: Condition marked by sudden attacks of sleepiness during the day.

Some Other Sleep Experiences

• Sleep talking: Talking during sleep.
• Sleepwalking: Walking during sleep.
• Lucid dreaming: Awareness of dreaming while dreaming.
• Periodic limb movement disorder: Unpleasant sensations and repetitive leg movements during sleep causing interruptions.
• Night terrors: Frightening experiences that wake someone up; characterized by screaming, sweating, racing heart, and flailing.

Descriptive Studies of Dreaming

• Most dreams are more threatening than pleasant.
• Dreams often relate to everyday thoughts and experiences; not all experiences are dreamt about.
• Vision loss (or acquisition) may influence dream experience.

Freud's Theory of Dreams

• Manifest content: The surface-level content of a dream.
• Latent content: The hidden, symbolic meaning behind a dream.

Modern Theories of Dreaming

• Activation-synthesis theory: Dreams arise from random brain activity during REM sleep.
• Neurocognitive theory: Dreams are a type of thinking under special conditions. (Reduced sensory stimuli, prefrontal cortex activity, and enough activity in other brain areas).

Hypnosis

• Hypnosis: State of focused attention and increased suggestibility within a special hypnotist-subject relationship.

Ways of Inducing Hypnosis

• Hypnotists use suggestions and rely on the hypnotized person's cooperation and willingness to accept suggestions.

Uses and Limitations of Hypnosis

• Hypnosis can: Inhibit pain, facilitate posthypnotic suggestions, and sometimes help break unwanted habits.
• Hypnosis cannot: Provide special strengths, enhance memory accuracy, or reliably result in improved memories. Memories reported under hypnosis might include a blend of correct and incorrect information.

Is Hypnosis an Altered State of Consciousness?

• Hypnosis is similar to normal wakefulness but distinct as people can pretend to be hypnotized.

Other States of Consciousness

• Meditation: Systematic procedure for inducing a calm, relaxed state characterized by reduced anxiety and enhanced attention.
• Déjà vu: Feeling that an event is familiar, which in some cases may correlate with abnormal brain activity in memory areas.

Explore the fascinating topic of consciousness in this quiz based on Chapter 9 of Introduction to Psychology. You'll learn about the evolution of psychological research on consciousness, methods to study stimuli perception, and evidence of unconscious brain processing. Test your knowledge on the complexities of conscious and unconscious experiences.