States of Consciousness Flashcards
Split-brain
Surgery that cuts corpus callosum (axons that connect 2 hemispheres of brain), therefore hemispheres can’t share information
Hemispheric specialization
Idea that 2 hemispheres have different functions
Conscious content
Subjective experience of internal and external world and is heavily dependent on the state of consciousness a person is in
States of consciousness
Refer to different levels of arousal and attention
Attention
Process of selecting info from internal/external environments to prioritize for processing (involuntary and automatic)
Passive vs active attention
Passive: Attentional priorities set by bottom-up (raw stimuli shapes perception)
Active: Attentional priorities set by top-down (shaped by goals, experiences and state of mind)
Selective attention
Occurs when person attends to some info while ignoring others
Stimulus salience
Idea that some stimuli in environment capture attention by virtue of their physical properties (bottom-up)
Attentional capture
When attention is diverted b/c of salience of stimulus
Cocktail party effect
Person can be engaged in convo and suppress/ignore surrounding info
When can attention be shifted to process something else?
When something is surprisingly, personally relevant or emotionally engaging
Dichotic listening
One stream of info is presented in one ear and another stream in another and participant is asked to pay attention to a specific side but is asked about unattended message
Divided attention
When person is engaged in 2 or more tasks simultaneously
Automaticity
Fast, effortless processing of info w/o conscious thought
- Note: Can still lower awareness of another task
Inattentional blindness
Tendency to miss changes to some kinds of info when attention is engaged elsewhere
Inattentional change detection
Attention task that requires participant to actively search for change made in stimulus (faster at identifying animate stimuli)
Inhibition
Actively reducing processing of some info while brain attends to specific task
Subliminal stimulus
Sensory stimulus that’s processed but doesn’t reach threshold for conscious perception
Subconscious vs subliminal processing
Subconscious: Aware of info from environment but not aware of its influence on behaviour
Subliminal: Can’t consciously detect info and has minimal/no effect on behaviour as far as research is concerned
Visual neglect
- Disorder from lesions on right/inferior parietal lobe that cause you to lose awareness of visual stimuli on the left, as if they weren’t there
- Processing of dorsal visual system goes to inferior parietal which helps identify location of visual stimuli
- Can still impact behaviour but patients won’t know why
How is Attention Deficit Hyperactivity Disorder (ADHD) diagnosed?
Minimum 6/9 deficits in attention AND hyperactive behaviours
Who were first interested in dreams and believed they were symbols/metaphors from the unconscious mind?
Sigmund Freud and Carl Jung
Fatal familial insomnia
Rare genetic disorder affecting thalamus that results in death b/c of insufficient sleep
Electroencephalograms (EEGs)
Measures sum of electrical activation across cortex’s surface
Electrooculogram
Used to measure eye movements
Electromyogram
Used to measure muscle tension around jaw
Frequency
Number of up and down cycles of the wave per sec measured in Hz
Amplitudes
Wave’s height
Regularity
How consistent/erratic waves appear
Awake stage
- Beta waves: Person is awake and alert; mostly low amplitude waves that are unsynchronized and erratic
- Alpha waves: Person is awake and relaxed; regular and predictable waves w/ medium frequency
Stage 1: Theta activity
- Theta waves: Person is deeply relaxed/falling asleep; firing rate becomes more synchronized and amplitude increases
Stage 2: Sleep spindles and k complexes
- Theta activity but waves are generally irregular
- Sleep spindles: Brief bursts of activity that happen 2-5 times per minute during NREM
- K-complexes: Pattern of neural excitation followed by neural inhibition
Stage 3-4: Slow-wave sleep
- About 15-20 mins after start of stage 2
- Delta waves: Person is deeply asleep; firing becomes coordinated; slow, regular, high-amplitude waves
- Deepest stage
Stage 5: REM sleep
- About 45 mins after start of SWS
- Rapid eye movement: Highly irregular unsynchronized beta and theta waves (similar to awake stage)
- Blood flow in brain decreases but visual association cortex and prefrontal cortex receive large portions of oxygenated blood
- REM sleep antonia: Sleep paralysis during REM caused by inhibited signals
- Repeats about 4-5x during 8 hrs of sleep
List some theorized functions of sleep
- Consolidation of memories (especially long-term and typically done by SWS)
- Resting cognitive function
- Consolidating info (typically done during REM)
Activation-synthesis hypothesis
Dreams have no purpose and are a consequence of other sleep processes
Evolutionary hypothesis of dreams
Dreams have biological significance thorugh increasing performance in life-threatening situations
Insomnia
Inability to fall/stau asleep
Sleep hygiene
Behavioural practices that promote ability to fall/stay asleep
Conditioned insomnia
Occurs when cues usually associated w/ falling asleep instead cause anxiety surrounding ability to sleep (self-fulfilling prophecy)
Idiopathic/child onsent insomnia
Neurological condition b/c of abnormality in CNS that causes inability to sleep
Hypersomnia
Excessive need for sleep/sleepiness during daytime hours
Sleep apnea
Patient stops breathing during night, causing CO2 to build up which causes patient to wake up
Narcolepsy
Sudden and extreme need to sleep
Cataplexy
- Muscle weakness/paralysis during waking hours and commonly associated w/ narcolepsy
- REM sleep at wrong times
- Initiated by emotionally engaging events
Hypnagogic hallucinations
Hallucinations right before onset of sleep
Hyponopompic hallucinations
Hallucinations right before waking
REM sleep behaviour disorder
Neurodegenerative disorder where brain doesn’t paralyze body effectively during REM
Night terrors
Frantic, panicked screaming during SWS but often little/no memory of episode that caused it
Somnambulism/sleepwalking
Execute complicated behaviours while in SWS
Biological clocks
Internal clocks that prep body for daily, seasonal and annual rhythms
Circadian rhythm
Daily body clocks that tell body when to sleep and wake
“Free running” cycle is closer to __ hours
25
Zeitgebers
Cues from environment that set biological clocks (e.g. absence/presence of light)
Jet lag
When one travels to a different time zone and body is out of sync with zeitgebers
Suprachiasmatic nucleus (SCN)
Structure of brain, next to optic chiasm, that sets body’s circadian clock
In response to light/dark the ___ ____ secretes _____
Pineal gland; melatonin
Psychoactive drugs
External substances that influence mood, thoughts and behaviour
Drug tolerance
Increased ability to tolerate drug after repeated ingestion, resulting in the need for larger doses to feel effects
Dependence
Individual requires drug to maintain normal functioning and will experience withdrawal if not
Withdrawal
Distress, restlessness and irritability b/c of reduced/discontinuation of drug/behaviour
Depressants and examples
- Slow/depress arousal of CNS
- Alcohol, barbiturates (sedation and induce sleep) and benzodiazepine (treat anxiety)
Glutamate vs GABA
Glutamate: NT creates excitatory effects in NS
GABA: NT creates inhibitory effects in NS
Dopamine
NT implicated in rewarding effects of some drugs
Stimulants and examples
- Increase activity of NS
- Caffeine, nic, cocaine, amphetamines
Adenosine vs acetylcholine
Adenosine: NT creates excitatory effect in brain
Acetylcholine: NT creates inhibitory effect in brain
Psychedelic drugs and examples
- Influence sensory systems and interpretation of reality
- Lysergic acid diethylamide (LSD), mescaline, cannabis/marijuana
Synthesia
Experience where senses seem to merge
3 factors that allowed humans to dominate planet
1) Bi-pedalism
2) Frontal cortex for complex movement (specifically right)
3) Language: Ability to transmit info across generations
Animal mirror experiment
Stage 1: Animal reacts as though new member of species was there
Stage 2: Animal ignores reflection b/c it has no informational value
Stage 3: Some re-enage and start “using mirror”, which may be evidence of self-awareness
