Psyc 100 Unit 7

what is consciousness

moment by moment awareness of ongoing experiences occurring internally and externally in the world around us

spotlight effect

conviction that others are paying more attention to oneself than they actually are

selective attention

act of focusing one’s awareness onto a particular aspect of one’s experience while ignoring irrelevant stimuli

inattentional blindness

failure to perceive information outside the focus of one’s attention

change blindness

form of inattentional blindness in which a person fails to observe a change in a visual stimulus

perceptual decoupling

shift in attention from external environmental stimuli to internal stimuli or thoughts

mind wandering

spontaneous, stimulus-independent thought

wandering mind =

unhappy mind usually. thinking pleasant thoughts doesn’t make u happy, but thinking about neutral and unpleasant thoughts make you less happy

automaticity

ability to perform a task without conscious awareness or attention

freudian perspective for the unconscious mind

hysteria = repressed emotions and traumatic exxperiences buried in unconscious mind

believe: conscious = focus of current awareness

preconscious = thoughts, feelings and memories that are not in current awareness but are consciously accessible

dynamic unconscious = inaccessible memories, instinct, and desires

freudian dynamic unconsciousness

influences thoughts, feelings and behaviors. ongoing conflict with the conscious mind. modern sees it more as a collaborator.

cognitive unconscious

mental processes that occur outside of conscious awareness but still influence thoughts, feelings, and behaviours

implicit memories

skills and tasks we perform automatiaclly

cocktail party phenomenon

ability to pick important information while focusing on other information. suggests that information is being unconsciously processed on another channel

dichotic listening task

headphones, with different messages to each ear.

Asked to shadow (repeat) one message

Appear to be unaware of message in unattended ear, BUT Pay attention to salient information (e.g., one’s own name)

Slower to repeat words from attended ear if words in unattended ear are synonyms

subliminal perception

processing of sensory information that occurs below the threshold of conscious awareness

mere exposure effect

tendency to like stimuli more after repeated exposure to theM

conscious and the unconscious

Our minds are capable of doing a lot of things unconsciously

Can monitor, understand, and respond to various aspects of our experience without awareness

But the conscious mind can “step in” and take control of behavior when the unconscious mind makes mistakes or encounters something threatening (like if the distractor image is a spider

reticular formation

• regulates arousal and alertness

• raises or lowers the threshold of conscious awareness

  • damage may result in coma

thalamus

Works with reticular formation to regulate arousal and wakefulness

Serves as “relay station of the brain”

Thalamic lesions also lead to profound loss of consciousness (e.g., Unresponsive Wakefulness Syndrome)

These regions are necessary but not sufficient for producing consciousness (E.g., like unplugging a TV)

spatial hemi-neglect

condition where individual loses awareness of objects/stimuli one side of the space following brain damage (like: damage to right parietal lobe à left side neglect)

global workspace hypothesis

consciousness arises from “broadcasting of information across a global workspace in the brain

Information from various specialized brain regions (e.g., sensory areas, memory centres) is integrated into a central “workspace”. Once integrated, this information is “broadcast” or shared with multiple other brain regions simultaneously

EEG matching task: Compare EEG brain activity for consciously perceived and non-perceived pictures of words. Greater neural synchronization across the brain during conscious perception

default mode network

interconnected set of brain regions (e.g., medial prefrontal cortex, lateral parietal cortex) that are active when the mind is alert and aware but not focused on a particular task (e.g., during rest and mind wandering)

Enables perceptual decoupling.

Less activity in DMN when engaging in task requiring focused attention on external stimuli

Overlaps substantially with areas involved in social cognition § One suggestion: may prepare us for making social inferences § Another suggestion: may facilitate social memory

locked in syndome

complete paralysis of voluntary muscles but preservation of consciousness and normal cognitive abilities

DMN connectivity decreased in severely brain-damaged patients (in proportion to degree of consciousness impairment) but not in locked-in patients

hippocampus

Plays a role in mental time travel

thinking about past events or imagining the future

Patients with bilateral hippocampi damage cannot vividly recall past events or envision future events

circadian rhythm

body’s natural 24-hour cycle that regulates various physiological processes, including the sleep-wake cycle

Determined by both biological & environmental factors

zeitgeiber

external/environmental cue that helps regulate & synchronize an organism’s biological rhythm (“time giver” in German) for example: Light, Food intake, Social interactions

supprachiasmatic nucleus

part of hypothalamus that regulates sleep and alertness.

contains rhythm-generating neurons that increase & decrease rate of action potentials over 24-hour cycle. Functions autonomously

Damage to this area results in loss of regular sleepwake rhythms

melatonin

regulated by rhythmic secretion of certain hormones, including melatonin.

important for regulating sleep, produced by pineal gland, secretion begins in the evening until time of awakening

entrainment by light

Suprachiasmatic nucleus is stimulated by light

Signal travels from specialized light receptors in the retina along dedicated neural tract to the SCN

Sleep-wake cycle can be lengthened or shortened by artificially changing periods of light and dark

Light exposure in the morning can help with sleep-onset insomnia

Artificial light at night may contribute to problems falling asleep

beta waves

state of arousal using EEG. low amplitude, high frequency, brain is actively processing informaiton

alpha waves

slower, larger waves. awake but relaxed

sleep stages

4 stages, increasingly large high amplitude slow waves

theta waves in stage 1 and 2 (lighter sleep)

delta waves in stage 3,4 (deep sleep)

stage 2 and early stage 3: also see special waveforms of K complexes and sleep spindles (supressing incoming sensory information, as well as learning and memory)

rapid eye movement (REM) sleep

90-120min after sleep onset

Cortical and limbic system arousal o Back-and-forth eye movements, Sympathetic nervous system activation, Vivid dreams, Muscular paralysis

REM behaviour disorder

usually: heightened activity in brain’s motor cortex but body muscles paralyzed, bc brainstem blocks signals from motor cortex.

disorder occurs when these signals are not blocked, so people act out their dreams. diff from sleepwalking

sleep cycles

90 min in length

Proportion of NREM and REM sleep in each cycle changes throughout the night

First half of the night: longer periods of NREM sleep (esp. stages 3 & 4) and brief periods of REM sleep o Second half of the night: dominated by REM sleep, stages 3 and 4 infrequent or absent in later hours of sleep

why we sleep

essential to life and lack of sleep is directly related to a decline in functioning

sleep stage 3 &4

role in body repair, Nearly all human growth hormone is released during these stages.

sleep deprivation associated with;

Slower healing of injuries

Impairments of immune system

Decreased neurogenesis

REM rebound

tendency to spend more time in REM sleep if deprived of it on previous nights

possible roles: Memory consolidation, Helping “wire” the brain

Infants, and especially premature infants, spend the most time in REM sleep

when we dream

REM

sigmund freud’s theory of dreams

form of wish fulfillment

manifest content (freud)

visible, surface content of a dream or behavior that disguises the hidden, latent content

latent content (freud

hidden drives and wishes

why we dream?

help sort through recent experiences, consolidate memories, solve problems

activation-synthesis hypothesis

dreams as a product of brain’s attempts to organize the chaotic patterns of brain activity during sleep into a semi-coherent narrative