PSY 212: Biopsychology Final Review 6 (Sensation and Perception)

What is it called when external information is changed into a signal our brain understands?

signal transduction

What do external stimuli change?

receptor potentials

What do sensory receptors not have?

axons (info goes straight to dendrties)

What are the five senses?

Vision, audition, somatosensation, olfaction, gustation

What is our most evolved, complex, and reliable sense?

vision

What is most cortical space in vision dedicated to?

visual processing

What is vision concerned with?

The detection of light stimuli

What wavelength can our eyes detect?

380-760nm

What can other organisms see?

UV or infrared light

What animals can see UV light?

birds and bees

What animals can see infrared light?

snakes

What are the three dimension of light?

1. Brightness

2. Hue

3. Saturation

What is hue determined by?

wavelength of light

What is saturation?

purity of light

What is brightness determined by?

intensity of light

What is responsible for moving the eye in various directions?

extraocular muscles

What is the outer covering of the eye that attached to muscles?

Sclera

What is the outer most mucous layer of the eye?

Conjunctiva

What is the outer most layer in front of the eye that is transparent and allows light through?

Cornea

What is the aperture that allows light into the eye?

pupil

What is the opening and closing of the eye controlled by?

Iris

What are the layers of tissue that change shape to focus light?

lens

What is shape changed by?

cilliary muscles

What is the fluid that fills the eye between the lens and the retina?

Vitreous humor

What is the back layer of the eye that contains the photoreceptors?

retina

What is the blind spot and a gathering of sensory axons in the area of the retina that contains no photoreceptors called?

optic disk

What does no photoreceptors mean?

no vision!

What are the movements of the eye?

vergence, saccadic, and pursit movements

What movement is when both eyes fix on the same target in coordinated movement?

vergence movement

What movement is a rapid back and forth movement scanning for stimuli?

saccadic movement

What are slower movements used for following objects through space and are usually deliberate?

pursuit moment

How many rod types are there?

1 type

How many cone types are there?

3 types

What are the interneurons connecting photoreceptors with ganglion cells?

bipolar cells

What are sensory neurons that form the optic nerve and enter the brain?

Ganglion cells

What cells parallel connections of the photoreceptors?

horizontal cells

What cells parllel connections of the ganglion cells?

amacrine cells

What segment of photoreceptors contain lameale and photopigments?

Outer-segment

What segment of photoreceptors contains nucleus?

inner-segement

Where are photoreceptor cells situated?

the back of the retina behind the ganglion and bipolar cells

What are the two parts of photopigments?

opsin and retinal

What are the photopigments of rods?

Rhodopsin

What is information from the nasal portion of both eyes processed by?

the contralateral portion of the brain (decussation)

What is crossing called?

decussation

What is information from the temporal portion of both eyes processed by?

ippsilateral portion of the brain (no decussation)

What is the relay station for vision?

LGN of thalamus

Where do optic radiations of the LNG project?

areas of striate cortex

What refers to the region in space to which any visual cell is sensitive?

receptive fields

What is the center of the retina?

fovea

What is the fovia's photoreceptor to ganglion cell ration?

1:1

What region of the eye is not adept at visual acuity but allows us to detect the presence of light in the periphery of our visual field?

periphery of retina

What do ON center ganglion cells respond most to most frequently?

stimulus near center of receptive field

What do OFF ganglion cells respond most to most frequently?

stimulus near the periphery of the receptive field

What produced contrast?

Lateral inhibition

What can inhibit adjacent photoreceptors and ganglion cells?

horizontal and amacrine cells

What did color vision evolve to do?

better identify fruits on a green foliage

What says that Opsin portions of the cones absorb a specific wavelength and are therefore color-specific?

Trichromatic Color Theory

Who do X-linked mutations in the cone genes that produce different types of color blindness affect?

males

What protonopia?

red cones have "green opsin"

What is dueteranopia?

green cones have "red opsin"

What is tritanopia?

no blue cones (rare and not x-linked)

What does red oppose?

red (red-green ganglion cells)

What does blue oppose?

yellow (blue-yellow ganglion cells)

What are some ganglion cells?

brightness detectors

What theory states that certain colors are a product of opposite reactions of a ganglion cell, hence they cannot coexist?

The opponent-process theory

Where is opponent processing transduced?

In ganglion cells downstream from cones

What is the occipital lobe region responsible for processing vision?

Striate cortex

How many layers is the striate cortex?

six

What happens when no stimulus is to cells in the striate?

No tonic activity

What are the three orientation-specific cells?

simple (orientation), complex (movement), and hypercomplex (edges)

What is color constancy?

we compensate for changes in light/darkness when detecting colors, thus they look the same under different conditions

What is damage to the extrastriate cortex called?

cerebral achromatopsia

What is the inability to identify a stimulus?

visual agnosia

What is the inability to recognize faces called?

prosopagnosia

What is gustation?

our sense of taste

What is gustation highly related to?

olfaction

People with what would have difficulties tasting certain foods?

anosmic

What is the combination of both gustation and olfaction?

flavor

What are the six tastes?

1. Bitter

2. Sour

3. Sweet

4. Salt

5. Unami

6. Fast

How many taste buds does the tongue contain?

~ 10,000

Where are taste buds arranged?

around the palpillae

What are the cranial nerves along the pathway to the brain during gustation?

VII, IX, X

What is the anterior 2/3 of the tongue?

fungiform papillae

What is the posterior portion of the tongue?

foliate popillae

What do you detect when tasting salts?

salt ions

What you do detect when you taste sour?

hydrogen ions

Why are sour receptors needed?

to tell of food has gone bad

What do you detect when you taste bitter?

plant alkaloids

What do you detect when you taste sweet?

sugars (gluscose, fructose, etc.)

What do you detect when you taste unami?

monosodium glutamate (MSG)

Bitter, sweet, and unami are all linked to what proteins?

transducin

What are bitter, sweet, and unami receptors all?

metabotropic

What does information from taste receptors intersect with?

facial nerve (chorda tymapni)

Where does information arrive to?

medulla

What is taste always represented as?

ipsilaterally

What is olfaction?

smell

What is one of the older evolutionary sense?

smell

What is the stimulus for olfaction?

oderants

What is the mucous membrane where oderants get trapped?

olfactory epithelium

What are olfactory receptor cells?

bipolar