Sensation, perception Flashcards
Weber’s Law
JND for a stimulus is proportional to the magnitude of the stimulus and that porportion is constant over most range
Signal detection theory
Effects of nonsensory factors, like experiences motives and expectations, on perception of stimuli
Cornea
Gathers and filters incoming light
Iris
Divides front of eye into anterior and posterior chambers. Contains dilator and constrictor pupillae, open and close pupil
Lens
Refracts incoming light to focus it on the retina and is held by suspensory ligaments connected to ciliary muscle
Aqueous humor
Produced by ciliary body, drains through canal of Schlemm
Macula
Mostly contains cones, especially in fovea at the center
Bipolar cells
Rods and cones synapse on these, which synapse on ganlglion cells
Sclera
White, structural part of eye
Vitreous
Bulk of eye on the inside
Visual pathway
Eye, optic nerves, optic chiasm, optic tracts, LGN of thalamus, visual radiations, visual cortex
Parvocellular pathway
Top four layers of retina-geniculate-striate pathway
80% of its retinal ganglion cells
Detect shape, High spatial, low temporal resolution
Magnocellular pathway
20% of retinal ganglion cells
Receives input from rods mostly,
Low spatial, high temporal resolution
Ossicles
MIddle ear
Malleus, incus, stapes
footplate of stapes rests on oval window. Connected to nasal cavity via Eustachian tube
Bony labrynth
Inner ear. Contains membranous labrynth. Filled with perilymph
Membranous labrynth
Contains endolymph, and consists of cochlea, utricle and saccule and semicircular canals
utricle and saccule (otoliths)
Detect linear acceleration
Utricle: horizontal
Saccule: vertical
Semicircular canals
Detect rotational acceleration (head)
Kinesthetic sense
Proprioception. Ability to tell where your 3d location is
Law of Pragnaz
Perceptual organization will always be as regular, simple, symmetric as possible
Information processing model
Brain encodes, stores, and retrieves info much like a computer
Piaget’s stages of cognitive development
Sensorimotor: manipulating environment to meet physical needs through circular reactions (object permanence), preoperational: symbolic thinking, egocentrism, centration, concrete operational: understanding the feelings of others and manipulating physical objects,
formal operational: abstract thought, problem-solving
Functional fixedness
Tendency to use objects only in the way they are normally utilized, which may create barriers to problem-solving
Heuristics
shortcuts or rules of thumb used to make decisions
Stage 1 sleep
light sleep dominated by theta waves
Stage 2 sleep
slightly deeper and includes theta waves, sleep spindles, K complexes
Stage 3/4
Deep (slow-wave) sleep. Delta waves predominate on EEG
Sleep disorders occur here NREM sleep
REM
paradoxical, mind appears close to awake on EEG, but person is asleep
Melatonin
Released by the pineal gland, result in sleepiness
Cortisol helps promote wakefulness
Dyssomnias
Insomnia, narcolepsy, sleep apnea,
Parasomnia
Night terror, sleep walking
Depressants
Alcohol, barbiturates, benzodiazepines, promote GABA activity in the brain
Stimulants
Amphetamines, cocaine, ecstasy. Increase dopamine, norepinephrine, serotonin concentration at synaptic cleft
Opiates
Heroin, morphine, opium, oxycodone.Can cause respiratory depression
Hallucinogens
LSD, peyote, mescaline, ketamine, mushrooms
Marijuana
Depressant, stimulant and hallucinogenic effects
active ingredient is tetrahydrocannabinol
Mesolimbic pathway
mediates drug addiction, includes nucleus accumbens, medial forebrain bundle, ventral tegmental area. Dopamine is main NT
Nativist theory
Explains language acquisition as being innate and controlled by language acquisition device
Learning theory
Explains language acquisition as being caused by motivation to communicate and interact with others
Whorfian hypothesis
lens through which we view and interpret the world is created by language
arcuate fasciculus
connects Wernicke’s area and Broca’s area
damage results in conduction aphasia
Conduction aphasia
inability to repeat words despite intact speech generation and comprehension
Photopic vision
High illumination, facilitated by cones to generate colored perceptions of high acuity
Scotopic vision
Low illumination, facilitated by rods to generate sensitive but less detailed perceptions
What is responsible for perceiving edges
Rods in retina, there are waaaay more
General ratio of rods to cones in eye
120mil to 6 mil so 20:1
High frequencies create more stimulation at which point of basilar membrane, and where in Sylvian fissure
Closer to base of cochlea, deep into Sylvian fissure
Low frequencies create more stimulation at which point of basilar membrane, and where in Sylvian fissure
Apex of cochlea , shallow region of Sylvian fissure called Heschl’s gyrus
Alpha delta fibers
Myelinated axons of medium diameter that are responsible for conducting information about temperature and fast pain
Retinal is derived from _____
Vitamin A
Upon absorbing a photon, retinal converts to its ___ form, which triggers a series of reactions which ultimately closes the _____ and the cell (hyper/de)polarizes
All-trans form. Sodium channel, hyperpolarizes
Rods and cones release NT ___ onto bipolar cells when depolarized in the dark
Glutamate (inhibiting them from firing)
