Psyc 100 Module 6

Consciousness

• Our immediate awareness of our internal and external states

Altered states of consciousness

• A change in a person’s ability to be fully aware of their external surroundings and internal states

States of consciousness

• Level of awareness for our external surroundings and internal states

  • Differentiated by the amount and type of attentions we’re able to pay to stimuli

Contents of consciousness

• Specific thoughts we are aware of about our internal states or external surrondings

Inattention blindness

• if you aren’t paying attention to something visual, you are unable to report on the details of what the visual stimuli contain

Reticular formation

• Role in being awake and, therefore, consciousness

• Damage results in inability to stay awake; associated with comas

Thalamus and hypothalamus

• An awake brain needs information processed

• Signals from reticular formation go to and through thalamus and hypothalamus

• Damage or dysfunction in these pathways can result in things like narcolepsy or comas

Cerebral cortex

• Important for the “awareness” aspect of consciousness

Our brain can be aware even if we are not

• The case of “blindsight” helps illustrate the separate roles of different parts of the brain in “sensing” stimuli and being “aware” of stimuli

  • Primary visual cortex destroyed, leading to blindness

  • But individuals could still point to a spot of light and dodge obstacles

  • This suggests that parts of the brain are still registering external visual stimuli but the individual is not aware of it

Development of Consciouness

• Conscious awareness of self (ie. noticing that you are a unique being separate from others) seems to develop around 18 months

• Full conscious awareness develops at around 22 months

  • This age is associated with more advanced language use, the ability to reason inductively, and categorize concepts

Preconsciousness

• Level of awareness in which information can become readily available to consciousness if necessary

  • it’s not currently in our awareness but it’s accessible

  • ex: what did you do last weekend?

Automatic behaviours

• a type of preconscious behaviour

• ex: do you remember every step each time you brushed your teeth last week?

Unconscious state

• state in which information is not easily accessible to conscious awareness

  • not the same as “being unconscious”

  • ex: what did you eat last weekend?

Implicit memory

• knowledge that we have stored in memory that we are not typically aware of or able to recall at will

  • the contents of our implicit memory allow us to perform a variety of tasks/ skills without thinking deeply about all the individual parts of the task/ skill

  • e.g. riding a bike, “gut reaction” decisions in high-stakes scenarios

Adaptive theory of sleep

• theory that organisms with bad night vision hide and sleep at night for the purpose of self-preservation, to keep away from predators

  • doesn’t fully explain sleep patterns in humans

Biological theories

• sleep plays a role in growth and development

restoration theory

• holds that sleep restores out brains and bodies; restores depleted resources, cleans up “waste” that has accumulated throughout the day

Circadian rhythm (biological clock)

• Pattern of sleep-wake cycles that in humans beings roughly corresponds to periods of daylight and night

• We experience changes in alertness and body temperature in predictable ways during sleep/waking

Suprachiasmatic nucleus (SCN)

• A small group of neurons in the hypothalamus responsible for coordinating the many rhythms of the body

  • Directs pineal gland to produce melatonin, which triggers sleepiness

• Sensory signals about daytime/ nighttime tell parts of our brain to prep for sleeping/waking

Controlling the Clock

• During the day, photoreceptors in the retina of the eye, send signals to the SCN about daylight, which helps regulate dopamine and melatonin production

• In the total absence of natural light, our SCN may extend our body’s “day” and disrupt our circadian rhythm

• We return to a natural rhythm quickly upon being exposed to natural light

Sleep Cycles

• Using EEG we can measure patterns of brain activity while people sleep

• Different patterns of brain waves denote different stages of sleep

• We go through these stages in order and on repeat

  • 90 to 100 minutes per sleep cycle (5 stages)

Pre-sleep period (hypnagogic state)

• Alpha waves

• Hypnagogic hallucinations

  • Vivid sensory hallucinations

  • e.g., “exploding head syndrome”

• Myoclonic jerk

  • Muscle spasm that accompanies hypnagogic hallucination of falling

Stage 1

• a few minutes

  • Bridge between wakefulness and sleep

  • Alpha waves change to slower theta waves

Stage 2

• 15 to 20 minutes

  • more relaxed

  • rhythmic breathing

  • sleep spindles (burst of rapid brain waves)

Stage 3

• Deep sleep

• 20% - 50% delta waves

Stage 4

• Heart rate, blood pressure, breathing rates at lowest levels

• Muscles relax

• Sleepwalking more likely

Stage 5

• Rapid eye movement (REM) sleep

Rapid eye movement (REM) sleep

• A stage of sleep is associated with rapid and jagged brain wave patterns, increased heart rate, rapid and irregular breathing, rapid eye movements, and dreaming

What are dreams?

• extra brain activity while asleep

Information processing theory of dreaming

• Dreams involve processing information from the day (ie., encoding memory and problem solving)

• Dreams could be a mental realm where we can solve problems and think creatively

Activation-Synthesis model of dreaming

• During sleep, the brain has a lot of random activity via brainstem activity that activates the sensory systems of the cortex

• Dreams reflect the brains efforts to make sense out of or find meaning in the neural activity that takes place during sleep

Freudian Dream Theory

• Dreams represent the expression of unconscious wishes or desires

  • Not much evidence for this theory

Nightmares

• Dreams filled with intense activity

Nightmare or dream disorder anxiety

• Frequent or distressing nightmares

Lucid dreams

• The sleeper fully recognizes that she is dreaming and occasionally actively guides the outcome of the dream

Daydreams

• Fantasies that occur while one awake and aware of external reality, but is not fully conscious

Sleep and Age

• Babies spend more time in REM sleep

  • Seen as evidence that this is part of how young brains develop

• Sleep requirements change as we age

Sleep deprivation

• If we could sleep as long as we wanted, most people would sleep 9-10 hours. But we don’t always get this

• Chronic sleep loss results in:

  • General depressed state

  • Lower immune system

  • Lower ability to concentrate

  • Higher incidence of accidents

  • Lower productivity and higher likelihood of making mistakes

Insomnia

• Most common'

• Difficulty going to sleep or staying asleep

• Caused by stress

• More common in older people due to medical conditions, pain, medications, and depression and anxiety

Sleep apnea

• Second most common

• Repeatedly stops breathing during night leading to frequent awakenings

• Possible to have hundreds of attacks per night

• Can lead to cardiac arrest

Excessive daytime sleepiness

• Chronically tired, even if slept well

Narcolepsy

• Uncontrollable urge to fall asleep

• Suddenly fall into REM sleep during the day

• Can last up to 15 minutes

• Genetic factors involved

• No cure

Delayed sleep phase syndrome

• Long delay in ability to fall asleep

Advanced sleep phase syndrome

• Fall asleep between 6 pm and 9 pm and wake between 2 am and 5 am

Restless leg syndrome

• Strong urge to move legs before sleep

Periodic limb movements of sleep

• Strong urge to move legs during sleep

Sleepwalking

• Mostly occurs during first three hours of sleep

• Eventually returns to bed

• Inherited

Night terrors

• Occurs in stages 3 and 4 of sleep

• Child screams in panic; goes back to sleep immediately and does not remember the event in the morning

• Resolves by adolescence

• May be genetic

REM Sleep Behaviour Disorder

• Acting out the dream while in bed and sleeping

Hyponosis

• Altered state of consciousness, with heightened suggestibility, deep relaxation, and intense focus

  • Posthypnotic responses

  • Posthypnotic amnesia

  • Hypnotic hallucinations

  • Decreased activity in anterior cingulate cortex when used to reduce pain

Divided consciousness theory

• Hypnosis splits awareness into two parts; one part responds to the hypnotist’s suggestion, the other part continues to process pain information but at a less conscious level

Social/cognitive process theory

• The participant is highly motivated to believe in hypnosis, and, without awareness, works hard to ignore the pain

Psychoactive drugs

• Chemicals that affect awareness, behaviour, sensation, perception, or mood

Addiction

• a psychological or physical compulsion to take a drug, resulting from regular ingestion and leading to maladaptive patterns of behaviour and changes in physical response

Tolerance

• mark of physical dependence on a drug, in which the person is required to take incrementally larger doses of the drug to achieve the same effect

Withdrawal symptoms

• Unpleasant and sometimes dangerous side effects of reducing intake of a drug after a person has become addicted

Depressants

• Slow the activity of the central nervous system, reducing tension and inhibitions

  • Include alcohol and sedative-hypnotic drugs

  • Can interfere with judgement, motor activity, and concentration

Sedative-hypnotics (benzodiazepines)

• Produces relaxation and drowsiness; relieves anxiety

  • Ex: xanax, ativan and valium

Opiods

• Derived from the sap of the opium poppy

  • Include opium heroin, morphine, codeine and OxyContin

  • Activate the opioid receptors in the brain, providing their analgesic effect and their related high

  • Reduce pain and emotional tension and produces pleasurable and calming feelings

Stimulants

• increases the activity of the central nervous system

  • Include caffeine, nicotine, cocaine and amphetamines

Cocaine

• Increases energy and alertness

• Produces euphoric feelings of well-being

• Negatively impacts memory, attention, and decision making ability

Amphetamines

• Small doses increase energy and alertness and reduce appetite

• Large doses produces intoxication and psychosis

• Includes methaphetamine (crystal meth) and MDMA (ecstasy), Adderall and others

Hallucinogens

• Produce sensory of perceptual distortions called hallucinations

  • LSD

  • magic mushrooms

  • Mescaline

  • DMT

  • Ketamine

  • PCP

  • Cannabis

LSD

• Drastically strengthens visual perceptions (including illusions and hallucinations) along with profound psychological and physical changes

Cannabis

• Produces a mixture of hallucinogenic, depressant and stimulant effects

Reward - deficiency syndrome

• People might abuse drugs because their reward centre is not readily activated by usual life events