Studies the relationship between the nervous system and behaviour (researchers)
- Attempt to map the brain to psychological characteristics
- Skull shape doesnt reflex cognitive functions and personalitiy
-assess cognitive function in people with brain damage
-accommodate language and culture
damage to the of the brain that results is destruction of neurons
Measures electrical activity via electrodes on the skull
Excellent temporal resolution
Excellent at studying when brain activity is changing
Can measure brain activity within milliseconds
Non invasive
Poor spatial resolution
Tough to pinpoint specific areas of activation
See brain structure, function or both
multiple X-rays to construct a 3D image of the brain
- magnetic fields to indirectly visualize brain structure
- measures the release of energy from water in biological tissues following exposure to a magnetic field
- MRI superior to CT for detecting soft tissue, like brain tumours
measures changes in brain activity in response to stimuli
- Measures consumption of glucose-like molecules to give a picture of neural activity
-Requires the injection of radioactive glucose-like molecules
- Do little to no harm
- Uses magnetic fields to visualize brain activity using changes in blood oxygen level
- Brain cells use more oxygen when they’re working
- Gold standard in functional brain-imaging research
- During rest the brain is still active and has spontaneous thought and daydreaming
- Advantage, excellent spatial resolution
-Disadvantage, poor temporal resolution
- Measures tiny magnetic fields generated by the brain
- Patterns of activity on the skull’s surface
- Excellent temporal resolution (within milliseconds)
- Fairly good spatial resolution, but not as good for deeper parts of the brain
- Images shown in neuroimaging studies show activating of experimental condition after subtracting activity of control condition
- A comparison of activity, not direct activity
When areas of the brain are active, we don’t always know whether the neurons are exciting or inhibiting other neurons
when people think brain scans are more scientific than they actualy are
unwarranted confidence
- Modify brain function through electrical stimulation from implanted electrodes
- Potential treatment for disorders (e.g. Parkinson’s Disease, - Depression and more)
- Invasive and risky
- Requires surgery on the brain
- Risks: infection, hemorrhaging, replacement of battery
- Applies strong and quickly changing magnetic fields to the surface of the skull
- Can either enhance or interrupt brain function
- Non-invasive
- Can infer causation (directly manipulate brain areas)
- May provide relief for depression and decrease auditory hallucinations
10%
- May originate from William James -> most people fulfill only a small percentage of their intellectual potential
- Losses of even small areas of certain parts of the brain can cause devastating, often permanent losses of function
- No investigator using brain stimulation or neuroimaging techniques has ever uncovered any consistently silent areas
when resting, the brain is still active
-brain cells that have communication with eachother
- 86 billion neurons with 160 trillion synaptic connection between them- van-halifax 5x
- contains genetic material and the parts necessay to make proteins
-outer covering of the cell that enables it to exchange electrical and chemical signals with other neurons
-Communication with other neurons
- Centre of neuron; builds new cell components
- Contains nucleus (where proteins are manufactured)
- Serious damage to this part is fatal for the neuron
branchlike extensions that receive information
"tails" that transit information
- spherical sack containing neurotransmitters
- knob at the of the axon
chemical messengers that allow neuron-neuron communication
space between neurons through which neurotransmitters travel
- glue
- 1:1 ratio with neurons
- play a rold in psychological functioning
- Astroglia and aligodedroglia
-Shaped like a star
-most abundant type of glial cell
-increase reliability of neuronal transmission
-Found in blood-brain barrier -> a protective shield of blood vessels that insulates the brain from infection
-Promote new connections and produce the myelin sheath around axons
-insulates axons and speeds the transmission of electrical signals down the length of the axon
-Wrapper around axons
-Multiple Sclerosis -> deterioration of Myelin sheath
Signals can’t travel down axon as efficiently
-has electric potential,neurotransmitters can change this potential
membrane potential when the neuron is not being stimulated or inhibited
-electrchemical impulse travelling down the membrane that results in the neurotransmitter is released
- how neurons communicate
-requires stimulation to threshold of excitation
-Abrupt waves of electric discharge triggered by a change in charge inside the axon
-This is the neuron “firing,” all-or-none response
-Neurons either fire or do not
-Originates near cell body and travels down the axon to the axon terminal, triggering neurotransmitter release
-Neurons can fire 100 to 1,000 times per second
-In between firings, there is a very brief absolute refractory period
-Absolute refractory period -> Brief interval during which another action potential can’t occur
-The longer the axon, the more limited their maximal firing rate is
-Communication inside neurons is electrical, but communication between neurons is chemical
-When neurotransmitters are released, they bind with receptor sites of the next neuron
-Lock and key -> Certain neurotransmitters fit in certain receptor sites
-This process is halted by reuptake, when neurotransmitters go back into the axon terminal
-synaptic vesicle reabsorbs the neurotransmitter
-Some neurotransmitters excite while others inhibit cells
-Each neurotransmitter has a specific role and function in brain and body function
-in the central nervous system
-learning and memory
-excitatory and increases the chance of neurons will communicate
-toxic in highdoses, may contribute to schizophrenia and other mental disorders
-inhibitory, dampening neural activity
-influences arousal, selective attention, sleep and memory
-connects to muscles that release acetylcholine and triggers movement
-benadryl, helps you sleeo and blocks acetylcholine
-contains one amino acid
- norepinephirine (brain arousal, mood, hunger, sleep. amphetamine and meth)
-dopamine (motor function and reward, parkinsons and schizophrenia)
-Serotonin (mood, temp, regulation, aggression and sleep cycles, treatment and depression)
-eating, motivation, memory and sleep
-binf the same receptors as THC (weed, munchies and sleepliness)
-short strings of amino acids
-endorphins, relieves pain (morphine)
-some regulate hunger others learning and memory
interact neurotransmitter systems and affect mood, arousal and behaviour
-increases activity of the neurotransmitter system
-opiotes (codeine and morphine), mimic endorphin
- some drugs block reuptake
-decreases activity in neurotransmitters
-dopamine blockers for schizophrenia
-fake neurotransmitters that bind to receptor sites but dont exert the effect
-ability in the nervous system to change
-highest when we are babies
-not hardwires and can change overtime
-different areas of the brain have different time frames for plasticity
1. growth of dendrites and axons
2. synatogenisis, formation of new synapses
3. pruning, consisting of death of certain neurons and the retraction of axons to remove connections that arent useful (70% die off)
4. myelination, the insulation of axons with myelin sheath
rely on 2 eyes, left and right eyes transmit different info
-nearby objects make our eye muscles to turn our eyes inwards
-judge depth
-strengthening of existing synaptic connections
-neurotransmitters released into synapses produce a stronger and more prolonged response from neighbouring neurons
-A cell, often originating in embryos, that has the capacity to differentiate into a more specialized cell
-Stems cells have the capacity to make any cell, even neurons
-Researchers can implant stem cells directly into the host’s nervous system and induce them to grow and replace damaged cells
-Controversial -> Some people believe these cells are an early form of human life
generation of new neurons
- sensory info goes in and decisions come out
-includes brain and spinal cord
-controls mind and behaviour- nerves out the CNS are called the perpheral nervous system
-outermost part of the forebrain
- analyses sensory info
- higher brain function
- frontal lobe
-parential lobe
-occipital lobe
-temporal lobe
-preforms highly integrated functions
-corpus callosum connets the 2 parts with fibers that communicate
rely on one side of the brain then the other
language skills
reading writing
phonology
motion detection
facial expression
course language skills
simple speech and writing
tone of voice
perceptual grouping
face perception
yes, corpus collosum keeps left and right hemisphere communicating
motor function
language
movement
Profrontal cortex, thinking planning, language
broncas area, speech production
motor cotex, body movement
-Railroad foreman in 1848 in Vermont
-Tamping iron exploded and thrust into his head
-Destroyed most of his left prefrontal cortex
-Remarkable behavioral and personality changes following injury
-“No longer Gage”
-Upper middle part of cerebral cortex
-Specialized for touch and perception
-Communicates information to the motor cortex every time we reach, grasp, or move our eyes
sensitive to pressure, pain and temperature
lower part of the cerebral cortex
hearing
understand language
long term memory
autobigraphical memories
Temporal lobe
speech
language
comprehension
temporal lobe
hearing
temporal lobe
recognizing the configuration of features that match the objects (faces)
back of the brain
visual cortex, dedicated to seeing
info from primary-association cortex
association, through all 4 lobess, intergrates sensory to preform complex functions (size, shape, colour and location)
emotional centre
smell
motivation
memory
relays info from the sense organs to primary sensory cortex
controls internal bodily states
4 Fs (feeding, fighting, fleeing an fucking)
fear
excitment
arousal
spactial memory
damage causes inability to form new memories
back of the brain
connects cerebral cortex and spinal cord (relat station)
basic bodily function
brain stem
movement
traching visual stimuli
reflexes triggered by sound
brain stem
connects cerebellum and triggers dreams
brain stem
regulates
breathing
heartbeat
vital functions (puking)
brain stem
connects forebrain and cerebrak cortex
arousal
damage can cause coma
spinal cord
send messages to nearby neurons
connect sensort and motor nerves without going to the brain
spinal cord
automatic motor responses to sensory stimuli
-nerves outside th ecentral nervous system
-somatic nervous system, conveys info from the CNS to the muscles in the body controlling and coordinating voluntary movement
-auntomatic nervous system, controls involuntary actions of organs and glands
-active durning arousal
-fight or flight response
-increased heart rate, breathing and sweating
- rest and digestion
- opperates when there is no threat
-composed of DNA, containing everything a cell needs to reproduce
-genotype, gene set we have
-phenotype, obersavable traits
-dominant, mask other genes
-recessive, masked by other genes
-epigentic, gene and expression can be motified throughout life
-make organism better suited for the enviroment
-capacity to survive and reproduce
-human and apes share common ancestor from 6-7 million years ago
-human brains trippled in size and changed the cerebral cortex
-size of brain proprotional to size of body
-dolphins and apes have large relative brain size
- they have more complec social networks
-studies the relative impact of nature and nurture on psychological traits
-estimates heritability, % of the variability in a trait across individuals due to genes
- some traits are highly heritable (height) and some are not (religous)
1.family studies, examine whether traits rin through intact families
-families share gene and enviroment
2. twin studies, examine trait differences in monozygotic (identical) snd dizygotic(fraternal twins)
3. adoption studies, examines traits that adopted children share with adoptive vs. biological paretns
-selective placement, adopted to children are assigned to families with similar characteristics to biological families
-detection of physical energy
the brains interpretation of raw sensory data
-perception which does not match reality
-demonstrates the issue of naive realism
-the external stimuli converted by a sense receptor into neural activity
-the action or process of converting something and especially energy or a message into another form
-activation is highest when stimuli is first detected, then our response decline in strength
-keeps us from being overwhelmed by sensation
study of how we preceive sensory stimuli based on their physical characteristics
lowest level of stimuli we can detect at above chance performance (>50% of the time)
examples
- vision, a single candle 50km away
- hearing, a watch ticking 20 ft away
- smell, drop of perfume in a 3 eoom appt
-taste, teaspoom of sugar in a gallon of water
-touch, wing of fly dropped on a cheek from 1cm away
- JND,smallest amount of stimuli change humans can detect
-webers law, a constant proportional relationship between the JND and stimuli intensity
-stronger stimuli, higher JND
-weaker stimuli, lower JND
-theory regarding how stimuli are detected under uncertain condition
-detecting signal in noise
-change in auditory perception caused by visual speech
-hearing something different then what was said
-visual information influences touch perception
-when guy had no hand and had pain did rubber hang and felt releif
- wehn you experience cross modal sensations
- example
-sounds with color or color with taste
-bob dylans voice, taste of friend chicken
-letter and numbers have colour(grapheme-color synethsia)
-our brains organize the sensory data into meaningful concepts
-whats in our sensory feild
-what was there a moment ago
-what we remeber from the past
-when we select one sensory channel and ignore the others (bottleneck)
-
-dichotic listening, when people hear different messages delivered to left and right ears
-shadowing, reporting messages they hear
-people could only report the messages they attended to, but sometimes mixed in information from other ear
can notice important messages, such as yout name from a conversation that doesnt involve you
missing stimuli in plain sight when out attention is somewhere else
-failure to detect obvious changes in your enviroment
-role in traffic accident and air travel is intensively studied
-how does our brain combine all stimuli (touch, smell, taste)
-rapid coordinated activitiy make binding possible
-apple is one experience for us but many experiences for our brain
-
-we can only see a narrow spectrum of light, aniamls may see different spectrum
related to the amount of light reflected back to the eye
-color of light related to wavelength
-were maximally sensitive to blue, green and red
- mixing of these three types of signals occur
-additive, mixing light produces white
-subtractive, mixing pigments produces back
- white portion of the eye
-strong tissue arounf the eyeball
-helps protect th eeye and maintain the ball shape
-the coloured portion that controls the amount of light that eneters the eye
-usually blue, green or hazel
-hole where light enters the eye
transparent cells that focus light on the back of the eye
-keeps image in focus
-changes curvature to reflect light onto the back of the eye (accomodation)
-important to adjust for distance of object (close or far away)
-myopia (nearsightedness) trouble seeing far away
-hyperopia (farsightedness) trouble seeing close up
-glasses change the way light enters the eye to help correct either myopia or hyperopia
-presbyopia, when lens can over come the shape of the wye when we are young but is harder as we age
- membrane in the back of the eye
- part of the brain that converts light into neural energy (transduction)
-contains 100million sense receptors for vision
-central part of the retina
-responsiblr for acuity (sharpness of vision)
-necassary to read, drive, sew or just do anything that require fine detail
-receptor cells in outermost layer of retina, sensitive to light
rods,
-low light vision, not sensitive to colour
-dark adaptation, time in dark before rods regain max sensitivity to light (30 min)
-absent in fovea
cones
-requires alot of light as they are for colour vision and fine detail
-exits the back of the eye and is composed of the axons of tje ganglion cells
-causes a blind spor in the visual feild
-most of the axons go to the thalamus(sensory relay station) and then the visual cortex, but some go to midbrain (reflexes- turning our head to track stimuli
-different corticsl cells to respond maximally to different types of stimuli
-feauture derector cells, allows us to detect lines and edges
-simple cells, orientation specific slits of light in a particular location
-complex cells, orientation specific but less dependant on location
-colour vision based on our sensitivity to 3 primary colours (blue, green and red)
-3 types of cones, different cones are sensitive to different wavelengths of light
-explains colour blindness
-dichromats havw 2 types of cones (red-green dichromats have trouble distiguishing red and green)
-colour vision as a function of complementory, opposing colours (red vs, green or blue vs. yellow)
-green canada flag on white wall
-dramatic reduction in ability to see
-less than 20/200 vision
-objects at 20 ft appear as they would at 200 ft in a normally sighted person
causes
-cataracts, clouding of the lens
-glaucoma, disease that causes pressure on the eye and damages the optic nerve
- can cause reorganization of other sensory cortices and senses
-visual cortex becomes sensitive to touch (neural placticity)
-more cortex can be devoted to visual tasks (reading braille)
-echolocation, making noises to listen for sound that bounces off objects
-objects recognition deficit
-damage to higher visual cortical areas
-can perceive features of an object, but cant recognize the object as a whole
-ability of cortically blind patients to make correct guesses about appearance of things around them
-damage to primary visual cortex, blocks flow of information to visual association cortex)
-some visual information reaches visual association cortec through an alternative pathway
-the sense we rely on most after sight
-the perception of hearing is based on the physical properties of sound waves
-pitch, wave frequency (20- 20 000 audible sound)
-loundess, amplitude of the sound waves (dB)
-timbre, complexity of sound
-key organs involved in sound processing
-three main parts with different jobs, outter, middle and inner ear
-includes the pinna (skin and cartilage flap)
-ear canal, funnels sound waves to the eardrum
-occicles (hammer, anvil and stirrup) vibrate and transmit sound to the inner ear
-helps to amplify sound
-cochlea converts vibration into neural activity (transduction)
-contains thick fluid that vibrates form sound
chochlea
-inside the chochlea are the organ of corti and basilar membrane
-organ of corti, tissue containing hair cell with hairs that extend into chochleas fluid
-basilar membrane, membrane that supports the organ of corti
-specific location along the basilar membrane matches a specific tone and pitch
-accounts for high tones
-the rate at which neurons fire action potentials matches pitch
-accounts for low tones
-neurons alternate firing to process higher pitches
-neurons fire slightly out of sync with each other to reach higher rates for higher pitches
-not just tones but the arrangment of tones in a melody
-music that provokes "chills" boosted activity in the same brain regions correspondong to euphoric responses to sex, food and drugs
-olfication, smell
-gustation, taste
-go hand in hand and work together to enhance liking or diliking of some foods
-sense receptors are stimulated by chemicals
-odours are airborne chemical sthat interact with lining in our nasal passages
-smell, salty, sour, bitter, umami (fatty)
-taste is influenced by smell
-when olfactory neuron contains a single type of receptor that recognized odourants based on their shape
-simulat to neurotransmitters
-taste buds on the tougue
-bumps on the tougue
-taste buds transmit information to the brain
-certain regions of the tongue correspond to certain tastes
-only a weak trend for certain receptors to concentrate at certain locations
-good mix of receptors everywhere on the tougue
-many more tastebuds than usual
-may find common things (coffee, broccoli, sugary food) unbearably bitter or sweet
-odourless chemicals that serve as a social signal to members of the same species
-importance is unclear
-the typical pheromones detection system that mammals use (vomeronasal organ) is not well develpoed in humans
-3 body systems that work together
-somatosensory, touch and pain
-proprioception, kinesthetic sense or sense of body position)
-vestibular sense, equilibrium and balance)
-emotional component, some are more sensitive to pain
-gate control model, neural mechanisms in the spinal cord regulates awarness of pain
following the loss of a limb, someone might experience persistant phantom pain allocated to that missing limb
-could be responsive to mirror treatment
-propriception, our kinesthetic sense helps us keep track of where we are and move effciently
-muscle stretch receptors vs tendon force detectors
-information enters spinal cord, travels through the brain stem, thalamus to reach the somatosensory and motor cortexes
-vestibular, our sense of equllibrum to maintain our balance as we move about
-our balance is due to fluid filled semicicular canals in the inner ear
-info sent to cerebellum
-cinscious awarness is limited
-only become conscious when we lose balance or there us a mismatch with visual input
-optimizes technology to better suit out sensory and perceptual capabilitites
-we can use what we know about psychology and sensory systems to build more ergonomic gadgets and tools
-parallel processong, attend to multiple sense at once
-bottom up processing, whole is constructed from the parts
-top down processing, whole is modified by experiences expectations and goals
-perceptual sets, when expectations influence our perceotions (top down processing)
- THE BAT (H and A look the same)
-allows us to perceice stimuli consistently across conditions
-we dont see size, shape and colour of an object changing despite the fact they do change
-colour perception in particular derives from contex
-involves analyzing an image in the contex of its surrounding and our expectations
-our brains fill in the missing information
-gestalt principles, rules that govern how we preceive objects as wholes within their overall context
-holistic processing, ability to visualize a face as a whole rather than the sum of its parts
-prosopagnosia, face blindness, lack the ability to oricess facial features holistically (chuck close, artist with prosopagnosia)
-to determine motion, the brain compares visual frames of what is to what was (frames in a movie)
-cant string frames thet see into the perception of ongoing motion
-eg. cant see a cup of coffee, one second its empty the next its overflowing
-can be tricked into seeing motion(circle thingy flashing not moving)
-illusory perception of movement from successive flashes of images
-perceptions of movement based on partial information, brain makes best guess about whats missing
-monocular, one eye
-binocular, two eyes
-monocular
-depth perception in stationary scene
-more distant things look simular
-texture less detailed with far away objects
-objects closer blocks objects farther away
-linear perspectives,outlines of rooms or byildings converge as distance increased
-vanishing point, point at lines would meet
-distant objects appear higher
-objects cast shadows that give us a sense of their 3D form
-nearby objects seem to move faster than farther away objects moving at the same speed
-left and right eyes tranmit different information for near objects but more simular information for nearby objects
-brain can use information to judge depth
-when we look at nearby objects our musckes to turn our eyes inward
-brain can use this information to judge depth
-visual cliff
-hesitation as a 6 month old
-demonstrates that depth perception is partly innate and result in experience
-binaural cue (2 ears),
different in time between ears
difference in loudness between ears (direct path vs. shadow)
-monaural cue (one ear)
shape of pinna reflets sound from different directions in different ways
-understanding why we pisperceive information provides insight into how we make sense of our surroundings
-moon appears larger near the horizon
-we may process many sensory inputs unconsciously and many of our actions occur with little to no forethought or deliberation
-if we can detect stimuli without knowing it, does it change our behaviour
-the process of sensort informationthat occurs below the level of conscious awareness
-on behaviours and attitudes
-subjects exposed to anger related words were more hostile to others
-subjects exposed to religious words(saint, church and preacher)less likely to cheat
-effects disappears when subjects are aware of our suspect subliminal influences
-failry unlikely to produce large scale or enduring attitudes or decisional changes