Sensation involves transduction of the physical world into neural impulses.Perception involves binding these sensory impulses into a representation of the world.*brain neural impulse

tatsuji inouye-responsible for treating patients who survived-based on the bullet wound he could tell where the damaged occurred-discovered the back of the brain was for vision, and it was organized ( scotomas ) blind spots. -correlated where the damage was and the part if vision affected.

Sensory impulses are processed by distinct brain regionsPhysiological response (brain response)-> Sensory experience Physical stimulus -> Domain of sensory physiology (how activity affects your brain activity)

Psychophysics- the relationship between physical stimuli and the sensations about them that we experience.guatau fechnes-became physically ill-can he measure his mind???-invented a method to measure the mind-relationship between physical and the sensations we experience

Psychophysicists Study:1) Detection (can you detect it)(sensory) ThresholdThe quantitative (minimum) amount of a stimulus required to be detected.

absolute threshold-That intensity at which a stimulus is detected 50% of the time

when graphed right shift-higher threshold -lower sensitivity .

left shift- lower threshold-higher sensitivity. Hit- in reality yes and in the response was yes False alarm-in reality no and the response was yesMiss-reality was yes and response was noCorrect rejection- in reality was no and response was no

2) Discrimination (difference)By how much must the stimulus intensity vary to just detect a change?Called Difference Threshold or Just Noticeable Difference (JND)-Different amount

webers law- difference threshold varies to the standard stimulus in a linear way difference threshold = I K

difference theshold =0.5threshold = 3

K=difference in threshold/thresholdK=0.5/3=0.166difference threshold=4(0.166)

=664 (4 g candy) ^webers law For a stimulus to be detected as different from the comparison 50% of the time, the intensity of a comparison stimulus must change by a fixed proportion of the standard stimulus. Weber fraction=JND/%magnitude of the standard3) ScalingFechner’s Law -Uses Weber’s Law to reveal the relationship between the physical stimulus and sensation.--Sensation intensity increases proportional to the logarithm of physical stimulus intensity.VISION- Light is the result of electromagnetic waves.- Electromagnetic (light) waves can have different wavelengths.-Visible light takes up only a small amount of the electromagnetic spectrum.3nm wave length is x-ray3m wave length is FM radio

nervous system can detect a small amount of the electromagnetic spectrum… visible spectrum.

nervous system applies the color400nm-700nm-need light to see, light bounces off things-broad spectrum-light from the sun-pigment molecules absorb light -it gets reflected to your eye

black is the absence of reflected light

EYEthe white part- scleracoloured part-irisboarder between them-limbuscentre of iris-pupil can change its size small-constriction in a bright room large-dilation in a dim roompupillary response^

6 extra ocular musclesoutside of the eye

front viewmuscle closest to the nose-medial rectus lateral rectus other side of eye

muscle attach interior obliquebottom of eye-inferior rectustop of eye-superior rectus

muscle attach-superior oblique

profile in the middle, top, and bottom muscles attach

3 components 1-light detecting device (ex. eye)2-visual pathway 3-visual center

eyebrow and eyelashes is to keep vision non impaired. keeps away debris and sweat

cornea is transparentanterior chamber-aqueous humor

accommodation -shape change bringing things into focus close has a fat shapefar away has a thin shape becomes less flexible as you become older-harder (presbyopia)

strabismus-miss alignment of the eyeesotropia-one eye turns inexotropia-one eye turns outcould fix by changing muscle length- brain finds a way to ignore it

phototransductiontriangluar part-outter segment

pigmentcell body(nuclus)- inner segmentend of the thing-synaptic ending

it can tell when it absorbs light, it changes. communicates to other cells by the synaptic ending

light starts and then goes through

rods-120 million-located in periphery -respond to dim light

cones-6 million-located in fovea-respond to bright light

lateral projectinghorzontial and amacrine cells

forward projecting bipolar and ganglion cells

visual receptive fieldthe region of visual space to which a cell will respond

Colour VisionTrichromatic Theory - Young & Helmholtz (1800)Opponent-process Theory - Hering (1870)Dual process Theory - (1998)

Hearing

- The auditory system is designed to detect sound waves.- Air molecules are required to generate sound waves.Compression(top of wave )->refraction(bottom of wave )->compression etc.. produce a sound wave frequency high- waves short and talllow- longer. ex. 1 cycle per second= 1Hz , how many cycles pre second ex. 3 cycles/second= 3Hz

frequency codes –pitchamplitude codes –loudnesssoft 3Hz, distance between peak and trough is smallerloud 3Hz, distance between peak and trough is greater

decibels=dB0dB is the smallest detectable sound10dB is 10x smallest detectable sound20dB=100X30dB=1000X

60dB=conversation120dB=concert 140dB=immediate damage

simple wave- low frequency + simple wave- high frequency = complex wave

Human can detect all frequencies between 20Hz and 20,000Hz (young adult) 20-15000Hz (older adult)

Middle ear bones-malleus-incus-strump

cochlea-fluideardrum (tympanic membrane)-moves back and forth amplifies the signalA sound causesthe basilar membrane to wave up and down

Loudness is coded by (1) the degree of hair cell bending, and by (2) neurons that are activated only after a threshold level of hair cell bending.

Frequency theory states that the frequency of nerve impulses sent to the brain match the frequency of the sound. Place Theory states that sound frequencies are coded at different positions along the basilar membrane.

Sound localizationInteraural Time Difference - difference in the time it takes a sound! to reach each ear.!-- When a sound reaches both ears at the same time it is perceived to originate from a source directly ahead.-- When the sound reaches the right ear first it is perceived to originate from a source to the right. -- As the interaural time difference increases, the source of the sound is perceived to deviate increasingly from center. Taste smell touch

TASTEpapillae- little bumps on your tounge, not taste budsthe taste buds are on the sides of them.

-tastants molecules flow across the surface of the tounge and go into the grooves formed by the papillae-inside the taste bud it is made of a lot, complicated machine. collection of cells. -support cells, -chemoreceptor cells, air like things called microvilli surface of microvilli are receptors, bind tastes -combines and 2 nerves facial and glossopharyngeal with great affinity, produces a response -produces activity across the tounge, the brain communicates it. -50 % of our taste comes from smell

-taste buds small number around on your mouth approx. 9 thousand taste buds

SMELLodorant molecule is what creates the sensation of the smell, outer smell. get sucked up into the nasal cavity.nasal cavity-inner smelling

olfactory epithelium- a lot of blood vessels. very quick recovery. cells are called olfactory sensory neurons- they patrood out to the nasal cavity in to the cilia, called mucosa.(tips of cilia) -there for the sensation of smell, contains a lot of enzymes and stuff to protect your form illness. -provides of opportunity for odorant to become solubilizes. not all molecules will be solubilized.olfactory receptors- 350 different receptors- suited to a particular odor

40million receptors- allows us to detect about 10 thousand odors

defactory bulb-make connections with olfactory bulb neurons and their axons form what is called a olfactory nerve. many different receptors. starts to put it back together, pattern of activity. TOUCHskin is the largest organ in the body.

2 meters^24kg.

layers of skin1-epidermis2-dermis3-subcutis

teeth nails hair and brain dont have touch neurons. cannot feel if people touch it

some parts are more sensitive then other parts- inhomogeneous of the receptors

converting physical stimuli into neural impulses chemo transductionsmell taste

mechano transduction touch audition

photo transduction vision

outer-pigment start out with pigment (rhodopsin)absorbs light

light is made up of photons 1)photon is absorbed by pigment (rhodopsin) 2)as it absorbs light, it changes it structure.

causes a protein inside the cell to become activated( TRANSDUCTION) one can active 800 trandsucin

3)phosphodiestrase activated 70 can be activated

4)CGMP (goes down) eat up or clean break apart (broken down)

because of the channels of the side inward-only when CGMP is bound to it, if none it will closeremoved from the cell because of the CGMP-it is blocked, so no positive going in. so positive ions are going out, so the cell becomes more negative. so neurones become more positive.

outward channel-all the positive changes inside the cell go out of the cell though this channel.

PERCEPTIONBrain activity of the orgin of our perception-attention shapes your perception

dr. newsome- he did an experiment got a monkey to look at a computer screen that contained 100 dotstrained him to look at the screen and fixate on the screensome of the dots would move left or right, and all the other dots would move

randomly. certain collection of neurons prefer certain movement of the dots.

is our perception a result of brain activity?brain says left, eyes say right. the neurons produce a signal stronger then the stimulus. scientific evidence that shows that

-Attention to particular sensations permits filtering of less important sensations.

-Attention can be consciously directed, or guided by features inherent within sensory input.

shadowing- left and right people talking get tested on only one, you are able to ignore the one side your not paying attention to.

can turn your attention to one way or the other.some stimulus can shift your attention

top down is the interpation of the binding of the information

binding sensory input for perceptiongestalt princpals-similarty (our brains group like objects)-proximity (grouped together)-closure (wanting to close objects)-continuity Perceptual errors result when our perceptual system applies Gestalt principles incorrectly.

ConsciousnessOur moment to moment awareness of ourselves and our surroundings.It is (1) subjective, (2) dynamic, (3) and self-reflective.

Psychodynamic Theory:-Conscious -Preconscious -SubconsciousCognitive Theory: -Conscious – Unconscious-Controlled and Automatic Processes are harmonious

Emotional Unconscious- emotional state influenced by unconscious events

Modular Mind- Consciousness not a single entityperception emotion problem solving

Neural processing without conscious awareness.

superior colliculus "motion" helps you move away from moving objects not your visual cortex.Consciousness is dynamic but it also has a regular pattern, or rhythm.The natural pattern of our conscious state across time is called circadian rhythm.

eye send some to SCN SCN send to the pineal glandthe pineal glans then creates melatonin (relax)

day activity

retina is active (eye) highactivity in the SCN is highhibitory effect, so the pineal gland is low when pineal gland is low, melatonin is low

so then you are alert

nightactivity

eye is lowSCN is then lowcause the SCN is low, the pineal gland is not inhibited as much, causes high

inactivity it in the pineal glandthen the melatonin is high, (relax)

30% of our lives we sleep. live to be 70 years old, you slept for 21 years of it.

Restoration Model - sleep recharges our bodies. Critical for physical health.Evolutionary Model - inactivity at night promotes survival.Memory Consolidation - memories are strengthened during sleep.

SLEEPneural plasticity-i will leave this room with a different brain then i walked in with. that change is called neural plasticity

left and right eye base connection to neurons in the brain50% of your visual brain connects to your left and right eye

normal right eye, cataract left eye the right eye steals brain territory (80%-20%)

less change. sleep enhances neural plasticity- 50-75% of the population believe they have a sleeping disorder.Insomnia - chronic inability to fall asleep, maintain sleep, or experiencing restful sleep.Trouble falling asleep - young adults Trouble maintaining sleep - older adultsMost common sleep disorderNarcolepsy - inability to stay awake. About 1 in 1000 have this disorder.REM invades waking consciousness.to reach REM takes about an hour.for them it could just take minutes, transition into REM very quickly

cause of Narcolepsy in humans there is a genetic competent if you have a twin you have 30% chance of having it in general its only a /01% chance.some environmental factor

-neurotransmitter system (orexin) in the brainbeen linked to states of alertness and wakenessonly a small number of neurons have orexin, 15-20 000if there is a abnormality you see huge consequences to appearing like human narcolepsy mice- low orexin-symptoms of narcolepsydog-mutation to orexin receptor-symptoms of narcolepsy humans- orexin disruption-linked to narcolepsy

cataplexy- muscle atoniainability to control ones muscles, they become relaxed, in respond the body just collapses.

cant move maybe some eye. Full muscle atonia- fully conscious just fully catapalatic

treatment can involve a sedative- they have sleep problems when they should be sleeping normally, so they are actually sleep deprived. so they will be more awake from a restful sleep from having a sedative. or a stimulant- take it during wake hours ( methylphenidate, ritalin )

REM Sleep Behaviour Disorder - REM sleep paralysis is inhibited.Thought to result from abnormalities in brain regions that inhibit motor movements during REM sleep.

Sleep Apnea - irregular breathing during sleep.Caused by sagging tissue that results when sleep induces relaxation of tissues.This prevents breathing until a survival reflex promotes a sudden gasp for air.

narrowing of the airway to the point ti gets blocked and the brain doesnt receive oxygenthe soft palate is irregularly shaped and is very relaxed, so the soft palate blocks the airway phonygeal wall when its blocked causes the huge gasp for air. treatment-sleeping on the back

-air mask produces positive pressure-get surgery- modify the shape of the soft palate or make it less flexible

Psychoanalytic Theory - dreams provide a means to engage inappropriate unconscious desires. -suppressing these shameful thoughts and when you sleep and dream that suppression is revealed and the shameful gross thoughts are shown in the dreams

Activation-Synthesis Theory - brain stem generates random patterns of activity that higher levels compare to perceptual schemamost biologically realistic -our brains are flooded from information of the world. -put it into a coherency to so can puts together pieces of information to a most realistic possibility -produces activity in the retina and braininterprets the random patterns of activity

Nightmares - Occur during REM sleep and present activity patterns similar to those found with pleasant dreams.Night Terrors - More intense than nightmares and produces arousal to a near terrified state.

DRUGS- Drugs alter consciousness by disrupting the fragile balance of neuronal molecules that permit normal function.- This is manifested as a change in synaptic transmission.it doesnt take much of a drug to create imbalance

the language of the brain is neural impulse.need cells to comminute with each other

presynaptic neuronaxon

post synaptic neuron dendrite

the that separates the pre and post synaptic, is the synaptic cleft

the left over in the cleft is taken up by something called the reuptake that takes it back up to the pre synaptic and then it can be reused again

drugs act upon 1-neurotransmitter system2-the receptor system3-reuptake system

Agonists enhance neurotransmission by:- increased release of neurotransmitter- direct activation of PS receptor- prevent

deactivation of neurotransmitterincrease receptor action (opiates)decease reuptake (cocaine)

Antagonists inhibit neurotransmission by:- decreased release of neurotransmitter - block PS receptor bindingPCPA-decreases serotonindecreasing receptor action (antipsychotic)

Tolerance - decreased responsivity to a drug in an attempt to maintain homeostasis.

after taking the drug, you body changes to make the drug less effective

neurotransmitter things attch, and is let out into the cleft

receptors­collection of protiens.

bind with the neurotransmitters

causes a change in the receptor signal  

casade te leads to neuro transmission

drug useover 5 months…goes up every month needs more.

drug effect over 5 months…first month doesnt need as much to get to the "ideal" but need more and more to get the same "ideal" effect each month

body creates a antidrug-started in the body to counter the amount of heroin have to keep over coming the antidrug, by taking more drug. -compensatory response

once you say no more drugs… takes body a while to realize that you’ve stopped taking drugs. no drug but there is still the antidrug, which makes you feel less then great.

Withdrawl - results from compensatory responses that are engaged to maintain homeostasis. -once you stop taking drug all you have in the antidrug, which makes you feel bad.. but will eventually go away (having symptoms of withdrawl)

- The brain of a drug user learns to compensate.when you are in a familiar environment the brain tells your body you are about to take the drug when you are in a unfamiliar environment- no protection from this amount of drug, result is less then great.. result is that he dies.

the compensatory response happens before the drug is taken- in a familiar environment more likely to relapse

- Drug addition is diagnosed when tolerance or withdrawl have developed.Myths: (1) Tolerance leads to withdrawl - LSD (2) Tolerance is required for dependence(3) Physiological dependence causes addiction

Stimulants - increase nervous system activity. Often used to promote euphoria and alertness.Depressants - decrease nervous system activity.Opiates - pain relief and mood changes. Euphoria can come with a heavy price.Hallucinogens - “mind-altering” drugs. Natural and synthetic forms.Marijuana - hallucinogen or depressant. Myths: apathetic, conduit to heavy drugs, not harmful.

Hypnosis is a state of consciousness characterized by a heightened degree of suggestibility.

Dissociation Theory - division of awareness into two streams of consciousness.Social Cognitive Theory - expectation and readiness promotes the success of hypnosis.

We will “see” what we want or expect to “see”.

Quiz questions

Q. Many experiments have demonstrated the impact that visual experience has on our perception of the world. The Muller-Lyer illusion occurs when a line appears longer when the V-shaped lines at its ends radiate outward rather than inward (as is shown in your textbook). Cross-cultural research on this illusion has found that: A. people who live in more rounded environments are less affected by the illusion.

Q. Electromagnetic energy can be characterized by its wavelength.____________ is an example of a short wavelength, while ________________ is an example of a long wavelength.

A. an x ray, a radio wave

Q. As we get older, the auditory system commonly changes so that we are less sensitive to which of the following:A. high frequencies

Q.When you leave a room with dim lighting and enter one with bright lighting, your pupil:

A. constricts

Q. Alexis is participating in a perception experiment where she will be paid $10 for every letter she sees flashed briefly on a computer screen. If Alexis says there is a letter but there is not, she is not penalized – she just does not receive $10 for those responses. Given this situation, Alexis will do well financially to set her decision criterion ______.

A.low; she'll commit more False alarms but also increase her “hits”

Q. According to Weber’s Law regarding the difference threshold (delta I), as the standard stimulus (I) increases, Weber’s fraction (k) will do what?

A. will not change

Q. Opiates bind to and _____________ receptor sites that are usually activated by ___________. A. activate; endorphins

Q. The theory that sleep enables a restoration in the brain points out that a cellular waste product called _____________ accumulates during waking hours and Is restored to baseline levels by sleep.

A. adenosine

Q. The hormone ___________ is secreted from the pineal gland and it is known to have a relaxing effect on the body. It plays an important role in the regulation of circadian rhythms.

A. melatonin

Q. The two primary effects of drugs called ____________ are to reduce pain and to induce euphoria.

A. Opiates

Q. Which of the following is a sleep disorder that is characterized by sudden entry into REM sleep during times when one would normally be awake.

A. Narcolepsy

Q.In an effort to block the negative consequences of sleep deprivation, the human brain will experience ___________. A.microsleeps

Q. As you become drowsy and relaxed your brain waves are mostly made up of ______________, but when you fall asleep and enterstage 1 sleep your brain waves are replaced by slower ___________ waves.

A. alpha; theta Q. Which of the following brain structures has been implicated as being critical for circadian rhythms?

A. superachiasmatic nucleus