Parts of the eye:•Protects the eye and bends light to provide focus?•Small adjustable opening that allows in light?•Colored muscle that controls adjustable opening?•Adjust its thickness to focus an image onto the back surface of eyeball? TERM for adjustment??•Light sensitive multilayered tissue that transduces electromagnetic energy into neural impulses?•Photoreceptors that enable color vision; buried in back of retina?•Photoreceptors that enable black and white vision; buried in back of retina?

• Photochemical reaction in retina triggers what cells?

• WHY do cones deal with fine detail? Direct route to what??

• Axons of what cells converge to create the optic nerve?

• Location where optic nerve leaves the eye to take neural impulses to the occipital lobe (visual cortex).

Rods/Cones – Bipolar– Ganglion – Optic Nerve

• Young – Helmholtz (Trichromatic) theory – retina has

three types of color receptors, each sensitive to one of three colors – green, blue, and red (other colors are combinations)

• Thalamus continues to process color – opponent process explains afterimage (cells that are stimulated by exposure to one type of light will be inhibited by exposure to opponent type of light wave) KNOW opponent sets (B/Y, R/G, B/W) Old Spanish Castle

• Feature detectors (discovered by Hubel and Wiesel) in the visual cortex process information such as edges, lines, angles, and movements (frog dying in sea of flies)

• Information if processed simultaneously, rather than sequentially in different parts of the brain – parallel processing – color, motion, form, and depth

Nearsighted – can see near, but far objects fall in front of retina because eyeball TOO LONG

Farsighted – can see far, but near objects fall behind the retina because eyeball TOO SHORT

Eardrum – membrane that separates outer ear from middle ear and is vibrated by sound waves being amplified by bones of middle ear - hammer, anvil, and stirrup

Inner ear after oval window contains cochlea and basilar membrane, which contains hair like receptors that transduce sound and send neural impulses to the brain (thalamus and temporal lobe) via the auditory nerve

Semicircular canals also in ear, which contain receptors for vestibular sense

Location of sound – stereophonic sound; cock head to one side when trying to pinpoint a sound

Place theory – allows high frequencies to be heard because of PLACE at front of basilar membrane that triggered

Frequency theory – allows low frequencies to be heard; basilar membrane triggers impulses to the brain that is at same rate as the sound wave up to 1000 waves per second

Volley principle – allows moderate frequencies to be heard by allowing alternate firing of neurons; 1000 to 4,000 sound waves per second

DIFFERENT pitched sounds are processed DIFFERENTLY!!!!

What’s being measured?

• Nanometers?• Hertz?• Decibels?• 130 decibel sound is how many times louder

than 100 decibel sound?

Conduction deafness – damage to middle ear; can’t hear certain amplitudes

Sensorineural (nerve) deafness – damage to inner ear; can’t hear certain frequencies

Charts:

Reddish colors / bass sounds

Bluish colors / soprano sounds

Height determines amplitude and intensity; bright / loud or dull / soft

ROY G. BIV

Other senses :Touch – receptors for pressure, pain, cool, and warmth, BUT onlyIdentifiable receptors for pressure

Taste – 4 gustatory receptors – sweet, salty, bitter, and sour (umami – proteins)

Smell – processed in temporal lobe; hotline to limbic system where emotions and memories processed; OLFACTORY receptors

Kinesthesis – receptors are in muscles, tendons, and joints – tells movement and position of body parts

Vestibular sense – sense of balance, whether body is upright or not; RECEPTORS are located in inner ear – semicircular canals

Gate Theory – Pain – Control theory - idea that only so much information can be processed at one time by the brain; pain activated by small fibers in spinal cord can be lessened by activating large fibers in the spinal cord

Lamaze uses distraction , counterstimulation, and relaxation

Firewalking only impressive IF you are unaware how poorly a conductor of heat wood is (example glass pan / cake analogy )

Things that affect sensation: (The Big Four)

Signal detection: shows how psychological factors (such as mood, setting, physical state) can affect the awareness of sensory stimuli; explains WHY thresholds can change

Absolute Threshold: weakest amount of stimuli that can be detected (50% of the time) – hearing test

- What happens to thresholds as vision/hearing get BETTER??

Difference Threshold: weakest amount of stimuli needed to detect difference between stimuli; jnd

- Weber’s law – difference between stimuli must be constant proportion

Sensory Adaptation: less response to unchanging stimuli, but more response to weak stimuli (dark adaptation)

Perception is reality to the perceiver!!!!

Sensation is stimulation of sensory receptors (detection), BUT perception is the interpretation of sensory information.

Bottom up processing is to sensation, and top down processing is to perception

Perceptual Organization: GESTALT says we like to find the “whole” / look for PATTERNS –

Closure: whole even with gaps

Continuity: ongoing rather than disrupted

Connectedness: uniform and linked; see as connected whole (ladder)

Proximity: nearness

Similarity: things that are alike

•Depth Perception: taking two dimensional retinal images and organizing stimuli into three dimensional perceptions

•Kant (innate) vs. Locke (learned) debate

•Visual cliff supports Kant that some depth perception is innate

•Some visual cues require BOTH eyes, while others require only ONE eye

• 2 Binocular cues and 8 Monocular cues

Binocular Cues - need two eyes to use these cues

• Retinal disparity – the brain compares the slightly different images received by each eye and the greater the disparity (difference) between the objects, the closer the object

- So, what happens to disparity as object moves away?

•Convergence – neuromuscular cue that allows brain to determine distance by how much eyes have to move inward (converge) to look at an object

- So, what happens to convergence as object moves closer? Away?

Monocular Cues: (popular way for artists to convey depth)Relative Size – if we assume that two objects are similar in size, we perceive the one that cast the smaller retinal image as farther away; can led to a driver thinking a smaller pedestrian is farther away

•Relative clarity – Because light from distant objects passes through more atmosphere, we perceive hazy objects as farther away than sharp, clear objects

•Linear Perspective – Parallel lines appear to converge with distance

• Light and Shadow – Nearby objects reflect more light to our eyes and if two objects assumed identical, the dimmer one seems father away; example car with only parking lights on seems farther away than really is

•Relative motion (motion parallax) – objects closer than our focal point appear to move backwards, while objects beyond focal point appear to move with you; farther away on object, the lower its apparent speed which the brain uses to compute distance

•Texture gradient – a gradual change fro ma coarse, distinct texture to a fine, indistinct texture signals increasing distance; objects far away appear smaller and more densely packed.

•Interposition - If one object partially bloc k our view of another, we perceive it as closer

• Relative height – we perceive objects higher in our field of vision as farther away.

Motion Perception:

Movies – stroboscopic – brain will interpret a rapid series of slightly varying images as continuous movement

Christmas lights – phi phenomena

Perceptual Constancies: perceiving objects as unchanging (having consistent lightness, color, shape, and size) even as illu8niation and retinal images change

Size – Distance Relationship- how moon illusion, ponzo illusion, the shrinking and growing girls, and

Muller-Lyer illusion all support that PERCEIVED size and PERCEIVED distance interplay and sometimes lead to mistakes; experience supports these illusions

Mueller-Lyer Illusion

Ponzo Illusion and Shrinking Girl

Vase Face Optical Illusion for Figure Ground

Old Lady - Young Lady

Perceptual Adaptation: In vision, the ability to adjust to an artificially displaced or even inverted visual field – animals can’t, humans can (after initial sickness in inverted experiment) – humans can adapt to context and coordinate movements based on experience

Perceptual set: a mental predisposition to perceive one thing and not another; once we have formed a wrong idea about reality, we have more difficulty seeing the truth

Schemas determine our perceptual sets, how we interpret ambiguous information with top-down processing; children’s drawings of human bodies show how schemas change with experience; this preference for human faces important in “lunar face” and focus of eyes and faces in paintings

Context effects: same stimulus can trigger different perceptions based on differing schemas, BUT also on the immediate context * brain can work backward to allow later stimulus to determine how we perceive an earlier one (eel becomes wheel instead of peel)

* Same monsters appearing “aggressive” or “frightened”

* Speaker said “cults and sects” or “cults and sex”, “attacks” or “ a tax” - determine by context of

surrounding words

* Soviet film director experiment – different context but same facial expression (pg. 254) – applied in hospitals “Kulechov effect” on how to transport dead body through crowded hallway

• The effects of perceptual sets and context show how experience helps us construct perception

• Human Factor Psychology – branch of psychology that explains how people and machines interact and how machines and physical environments can be adapted to human behaviors (Designers and engineers should consider the human factor, by designing things to fit people, by being mindful of the curse of knowledge, and by user-testing their inventions before production and distribution)

• Telepathy – mind to mind communication• Clairvoyance – perceiving remote events• Psychokinesis – “mind over matter” ; moving

things with the mind• Precognition – perceiving future events• Parapsychologists - psychologists that study

ESP (extrasensory perception)