3-5 Flashcards
Cell proccesses (neuron sticking out)
*Mulitpolar -
*Bipolar - (soma in the middle) found in the retina
*Unipolar - one process in sensory system
Resting potential
super costly 50% of briains energy. so almost 15% or 20% of all body engery.
Ion- means charged… NA+ sodium is let in. brief shift in neuron charge that travels downt the axon
Absolute refractory period
miminum legth of time after an AP when another Ap can’t start.
Larger Axions
faster axions
Sodium pump
3 NA+ out, 2K+ in
Overshoot of
Hyperpolarziation
synapse receptors
like a lock and key
8 steps of synaptic transmisson
- sythesis of NTs in Soma
- transportation and storage in vesicles
3 release - vesicles fuse wiht cell membrane/nt’s are released - binding - bind to receptors which influence postsynaptic cell
- decativeation acetylcholine and be destroyed in synapse so no longer an influence.
6.autoreceptor actiavation - NT’s bind to recpection of pre synaptic to reg step 1,2,3 Recycle - reuptake
- degradation
40 nm 7500 nm hair
synapse opening
Graded potential
additive. Not all or nothign
Cell assemblies
hebbian learning rule - when one regularily simulates the other. this is the basis for learning.
leads to LTP long-term-potentiation = a long lasting increase in excitablity in synapse in specific neural pathways.
LTP is critical to learning.
nerves are
bundlesof neurons
Agonist vs Antagonist
agonist - MIMICS NT (fits into receptor site)
antagonist - blocks action of NT (nicotine) doesn’t fit. Just binds
15-20 known NT’s at this point.
NT’s can be exicitiory or inhibiatory depending on the receptors thye bind too. (expect GABA) not all synapsies
ACh Acetycholine =
released by motor neurons controlling skeletal muslces. - attention -arrousal, nicotine is a agonist and im memory
DA
dyregulation - over activity and over all control
NE
can be made in the brain, not just adrenal gland. when it si nthe body it is a hormone -
boht NE and EP come from Ldopa snythesis
Seotonin
sleep arrousal
SSRI’s block reputake so there’s more seotonin
GABA
only inhibatory
endorphines
resemble opiate drugs - (endo) inside the body.
A and E
Attack - Afferent
Exit - Efferent
Hindbrain
Medula = circulation, breathing, muslce, reflexes
pons - sleep, arrousal
cerebellum - makes up 80’s of brains neurons
MidBrain
Reticular activating system, also in hindbrain.
Thalmus
no Smell. Hypothalmus (regulates) the thalmus controls
1300-1400 grams (3 pounds)
brain
glial
glue
csf
immunne
Soma means body
-70
1/20 the voltage of a flashlight
action potentials (1000 times per second)
Spatial summation / temporal summation
spacial at close dendrites - when I bunch Postsynaptic dendrites fires in at once
temporal - when one does over and over again
even for an eyelid to move millions of neurons must fire in unison
Lesioning
destorying parts of the brain
ESB
electrical stimulation of the brain
CT MRI EEG fMRI PET
computerized tomography
magnetic resonance imaging
electroencephalograph
positrong emisson tomography (chemical)
functionMagnetic resonance imaging
TRANScranila magnetic stimulation TMS
Medial forebrain bundle
primary somatosensory cortex (sulcus)
primary motor cortex
Mirror nuerons
Wernicke Broca
broca speech
wernicke - understanding
Sensation vs Perception
Sensation : stimulation of sense organs
Percetions : interpretation, organization of sensory input
70% of the nerves in your body sensory receptors are in the eyes
To see perceive or recognize something nearly half of your cerebral contra context needs to
involved
Light electromagnetic radiation travelling in waves
** wavelength Frequency** is hue (distance between peaks)
Amplitude height is brightness
Purity different wavelengths mixed is saturation (richness)
Psychophysics
study of how physical stimuli translates to psychologial experience
Sensation
starts with a detectable stimulus
Psychophysics threshold
detectable Threshold
Absolute vs Difference
depends on sensory capablities
- stim intestity can be detected all the time therefor 50% is ABSOLUTE
Absolute - the min amound of stim that can detected
380-700
JND and Weber
JND = smallest difference that can be detected (just noticable difference)
WEBER = JND is a constant propotion of the size of original stimulus
Generally the stimuli increases in magnitude the JND increases
SDT
Signal detection theory
detecting sensory info is influenced by sensory processes and decisiosn processes.
Stim (present v absent) vs preceiver response (yes v no)
Hit miss, false alarm, correct rejection
Sensory adaption
gradual decline in sensitivy due to prolonged exposure
The eye
1housing of neural tissue that receives
2 channels light towards retina
Cornea = bump in front of lens
Lens= short fat for close, thin for far away
Iris/pupil = regulates amount of light into the eye
fovea = only corneas, tiny spots
optic disk = spot nerves bunch together to leave the eye
Retina
Nerve tissue on the back of the eye
layers of cells - form circuits of r/c –> bipolar –> gangolian –> optic chiasm
Cones - colour, fovea 6 million
Rods = outside periphery and 100 million
Updown / Topdown visual processing
- sig processing occurs in retina before going to brain
- receptive fields in retina
bottom up - more time consuiming feature analysis feature detectors
top down - the whole, Stroop effect, percptual processing
Optic Chaism / Visual Pathways
point when nevers from each eye pass over
main pathway –> Lateral Geniculate Nucleus –> pvc (90% of cells synapse here). ** primarily glutamate excitable**
second pathway –> superior colliculus –> thalamus –>pvc corordinatioens with other snesory input
Perceptual processes in Vis System
interpretation and perceptual set=. set of readiness to preceieve stim in a specific way.
Inattenttional blindness
The higher the attentional demand of the takse, the more likely to filter out…
Could there be inattentive blindness in emotion?
Gorilla test
Auditory system = Sound
vibrations of molecules through physical medium
we can ony hear a portion of available range of sounds
frequency/wavelength - pitch
amplitude(height)- loudness (pressure)
purity- timbre (sound qualty)
Ear parts
External - Pinna - must turn head condense
Middle - ossicles - Hammer, anvil, stirup vibration
Inner - cochlea - fluid filled hair cells ** waves** nerve cells get stimulated basilar membrane
Ear processes
- sound waves funneled through pinna
- sound waves vibrate bones of mid ear via tympanic eardrum
- stirrup hits oval window of cochlea, moving fluid
- hair cells are stimed by move of basilar membrane (tube)
- physical stim converted to neural impulses
- nureal impulses sent to thalamas to auditory cortex in temp lobe
Organ of courti. Sodium channels
Utricle
BASIIAL MEMBRANE
Gustation
souable chemical substances - dissolvable in water and saliva)
taste buds in the trenches along the edges
sweet, sour, bitter, salty, umami
- taste is dependant on development and social perpections
-renewed every 10 days,
Papillae / papilla - are the groves
Each taste bud 50 - 150 receptor cells - micro. Villa -. take hair
TastesN depolarize the. cells. 7 9 1 0 solitary tract - thalamus - gusty cortex conscious
Awareness
Olfaction. Olfactory epithelium - ethmoid bone
-volitile - evaporated
-chemicals dissolved in mucus
- to the olfactory cilia
- through the bone and on to the bulb, along the olfactory tract
- doens’t go through thalmus
- smell influences taste
- taste depends on smell
- odurs aren’t classifiable to degree of other senses
-glomerulus- mitrel cell
40 minillion olfactor receptor neuerons…
Touch
physcial stimuli - mechanical, thermal, chem energy
six types of receptors
receptors –> spinal chord –> brainstem –> cross body –> thalmus–> somastosesory (PL)
pain receptors (free nerve endings)
fast A delta - thicker
slow -C fibre - non-mylenated, (1 to 2 secs slower) temprature
kinesthetic
joint - how much bend
muscle - tautness, extension
like propreioception, knowing where parts of the body are.
same pathway as tactile but they are kept seperate
Vestibular
sense of balance - gravity
semi-circular canals located in inner eary. above (vestibule) - room cochlea
Comparitors
things used a baselines
Ventral / Dorsal pathway
Ventral what
Dorsal Where
vison for perception, vision fo action
Agnosia
failure to recognize common objects
subtractive vs additve colour matching
additive - super impove
subtractive - remvoing some wavelength of light
human processing is closer to additive
Trichromats colour theory fo vision - Dichromats -
oppenent process of colour vision theory - holds htat colour perception depends on antagonistic response to three pair colours - (after image is an example of this)
Gesalt (whole is more important than the parts)
Figure and Ground
Closure
Similarity
Simplicity - law of pragnanz ( organize in good form or ways make sense
Continuity
perceptual hypothesis
people reconcile the gap between distal and proximal stim by testing what’s real in the world.
∴ we are constantly infering what distal stim is repsonsible for the proximal stim
distal vs proximal
stims in a distance
stims that touch (impinge) on receptors
perceptual hypothesis
binocular and monocular cues
binocular- Retinal disparity
convergance
monocular - paralax
pictoral depth cues
linear
texture
interpostion (relative size)
height in plane
light and shadow
balcetis and dunning
water bottle appears closer when you’re thirsty.
perceptual constancy
experience perception as stable perception depsite changing sens input
Visual illusions
muller-lyer
Ponzo - A
poggendorff - diagnoal segments
Zollner - long diagonal
upside down
Transduction (senses)
sensory cells translating chemical eltromagnetic and mechanical stimuli into action potentials that our nervous systems can make sense of.
photo receptors
mechano receptors
chemo receptors
Tast is 80
percent smell
gustory/ basil cells
gustory do the tasting
basil are stem cells that replace them.
taste pore
Consciousness is
awareness of internal and external stimuli
constantly changing - james an the Stream of conciousness
specfic parts - frontoparietal network and default mode network
levels of awareness
Freud what is happening below the surface.
consciousness dones’t come from any one specific brain structure by from levels of activity in neural networks throughout the body.
Brainwaves are
pyshological index of consciousness
freequencey (Cycles per second)
-Delta(<4 cps) Deep Sleep
-Theta(4-7 cps) light sleep
-Alpha(8-12 cps) deep relax, mediation
-beta(13-24 cps) normal walking thought problem solving
Biological Rhythms (circadian)
24 hour cycels found in humans and aniamls.
- critical for regulation of slepe
- produce rhythmic variations in various other bodiliy functions)
- vary from person to person
- chronotype- each personsl optimal time to fall asleep
biologiaal Rhythms (melatonin)
light levels –> retina –> suprachiasmatic nucleus (SCN) of hypothalmus –> pineal glad –> secretion of melatonin.
melatonin is a hormone that adjusts biological close
SCN
suparchasimatic nucleas syncs clocks throughout the brain and body
Sleep cycles - 4
N1 - brief transitional - 10 mins hypnic jerks, muscle contractsion
N2 - 10-20 mins mixed brain waves with sleep spindles (brief burts of activity)
N3 03 mins slow wave sleep
N4 REM, progressing longer and longer, similiar to awake but paraylisis
dreams can occur outside of REM
90 minute cycle, rem getting longer and longer.
RAS and sleep
Reticual activating System
afferent fibres run through reticualr formation that influence arousal (pons, medulla, thalmaus)
NT-s in sleep acetylcholine, serotonin (regulates)
Why do we sleep
hypo1- conserve ors energy
hypo2 - adaptive immobilize during sleep for safety(reduce danger)
hypo3 - helps RESTORE conserve engery and other resources
- memory consolidation? assimiliating new memories into existing framworks -learning and problem solving - promotes creativity and insight into promblems…. FIRMS UP LEARNING
Sleep loss
leads to worse health,
REM - slow wave rebound effect, you go right back to it again.
Insomina
Insomnia - most common - 35% have it, 15% frequently
ocurs in 3 different pattrens
-trouble falling asleep (young)
- trouble remaing asleep (middle age)
-presistent early monring awakening (middle and old age)
more common in men
Necrolepsy
go directly into REM
usuaully only lasts 10-20 mins
uncommon 0.05%
lost of orexin neurons in the hypothalamus
stimulates can work
sleep Apnea
reflexive gasping for air that awakens the sleeper
- usualy involes louds snoering,
- causes heart and lung damage.
100’s of times a nght
8% of adults - lifestyle and exerciese
males and olders aduts- can’t recall dreams
Nightmares
Anxitey arousig dreams that lead to awakening
usually durring REM
5% of adults, 10-50% of children
stress and ptsd - may hae difficulting geting back to sleep
Night Terrors
Intense autonomic arousal and maybe pain.
non-rem (usually slow wave)
quickly fades and little or no trouble getting back to sleep.
not indicativeof PTSD
Somnambulsim
15% Children 2.5% adults
tends to happen in 3 first hours of sleep.
causes unknown but is genetic
assocaited with sleep deprivation and stress.
stage n3
RBD (rem sleep disorder)
not having sleep aparalysis durring REM and acting out dreams
may invole yelling, moving limbs, leaping out of bed
mostly men in 50’s/60’s
sign of deterioration in brainstem structures neurodegenerative
DREAMS
mental experiences of sleep
typcially during REM, but can also occur during non-REM
DAY residue (freud spillover)
common themes
Theories of dreams
- wish fulfillment
freud- fulfill ungratified needs from daily life ( manifeest - plot of the dream) (Laten- hidden disguised meaning) - cognitive problem-solving
Rosalind carwright - cross country skiing - but just because we dream doesn’t mean we’re coming up with solutions - activation-synthesis
hobson-mcCarley
a side effect of neural activation - but then what about non REM dreams
Hypnosis
susceptibiilty = individual differennces
15% good, 15% bad
those who are susceptibile to suggsestion even when not hypnotised.
anesthesia
sensory distortions and hallucinations
disinhibition
posthypnotic suggestions amnesia
Theories of hypnosis
not well understood, not proved they’re put in alterd states
1. social cognitive theory:role playing
2. alter state of consciouness :dissocation
spanos and barber
social cognitive theory of hypnosis
people doing what they think they are supposed to do when they hypnotized (role playing)
role expectiation and not trace responsible for trance
but experts say dont’ think roleplaying because people act hypnotized even when alone, and there are difference in brain activity
DISSOCATION - argues that hypnosis splits consciousness into two streams. 1. external world with hypnotists and 2. hidden observer
Meditation
Focused attetion = tries to concentrate on one mantra or object or idea while shutting out other ideas
open monitoring = being mindful of receiving sensory and other stimulation in objective, non judgmental fashion.
some types blend them togehter
physiological benefits = relaxed EEG
CT scanes show hig PFC activity and low Parietal lobe activity, may expalin tanscendant experiences
DRUGS psychoactive
drugs that modify mental, emotional, or behaviour fuctioning
1)narcotics (opiods)
2)sedatives
3)stimulates
4)hallucinogens
5)cannabis
6)alcohol
Opiodes narcotics
reduce pain, overwhelminng sense of euphoria, (heroin, morphine, codeine, demerol, methadone, oxycodone, fentanyl
sedatives
sleep inducing -
(barbiturates, downers)
Stimulants
increase CNS activity
alterness excitement - euphoric
includes caffeine, nicotine, cocaine, amphetamines
Hallucinogens
pleasent or nightmarish
distored sensory and perceptual experience
(LSD, mescaline, psilocybin)
5.Cannabis
hashish, marijuana
THC is the active chemical which causes mild, relaxed euphoria, and enhanced sensroy awareness but unintented effects can be anxiet and sluggish functioning an memory imparement
6 alcholol
most widely used,
euphoria, boosts of self-esteem, and decreases inhibitions
impairs motor fuctions and results in mood swings.
you can die from withdrawal
MDMA
may have long term effects
produces warm friendly euphoria
compound is related to amphetamines and hallucinogenes
factors influencing experinece of drug use
age/weight/mood/motivation/exexpectation of effect/ previous drug experience
setting and novelty can greatly effect the potency
Drug dependance
physical dependance -
withdrawl symptoms (conditioned response) alcohol and opiods
psychological depenance-
must continue use to satisfy mental and emotional cravings. rare with hallucinongens
