PSYC Exam 2

Wavelength association

Wavelength of visual light is associated with our perception of colors of the spectrum

Short Wavelength

blue, violet

Middle wavelength

green

Long Wavelength

Red

Wavelength

distance between successive crests of a wave

Amplitude

distance between the resting position and the maximum displacement of the wave

Frequency

number of wave cycle that pass a fixed point in a given unit of time, typically measured in cycles per second, or Hertz

Rods

vertebrate photoreceptor; highly sensitive; primarily dim-light vision

Cones

vertebrate photoreceptor; bright-light vision, color, and visual detail

Intrinsically photosensitive retinal ganglion cells (ipRGCs)

contain melanopsin and detect overall light levels, especially for circadian rhythms, pupil responses

Parietal-eye photoreceptors

found in some reptiles and amphibians. associated with the pineal/parietal eye and detect light for physiological regulation rather than detailed images

Vision

active sensory process where the eyes and brain convert light waves into meaningful pictures and perceptions of the worldL

Light

electromagnetic radiation that can be perceived

Iris

a flat, colored, ring-shaped membrane behind cornea of eye, adjustable circular opening in center

Pupil

hole located at center of iris that dilates and contracts allowing light to fall on retina

Sclera

white of the eye, covering and protecting entire globe of the eye

Cornea

transparent front part of the eye that covers iris, pupil, and anterior chamber; in humans contributes most focusing power

Lens

transparent, biconvex structure of the eye

Choroid

vascular, pigmented layer of the eye

Retina

inner-most, light-sensitve tissue of the eye

Vitreous Humor

clear gel that fills space between lens and retina

Aqueous Humor

transparent fluid secreted by the ciliary bod; fills anterior and posterior chambers of body

Ciliary Body

controls shape of lens and secretes aqueous humor

Macula

pigmented area in center of the retina in humans; constitutes center of out visual field (detail, color vision); yellow in color under red filtered light

Fovea

small central pit of macula, composed of tightly packed cones

Optic Nerve

transmits light information to the brain

Rod shape

large and cylindrical

Cone shape

small and tapered

Rod distribution on retina

Peripheral retina

Cone distribution on retina

concentrated in center; 100% in fovea

Rod photopigment

Rhodopsin

Cone photopigment

Iodopsins (3)

Rod specialization

motion, dim light

Cone specialization

color, detail, bright light

Principle of univariance

once a photon of light is absorbed by a visual pigment molecule, the identity of the light’s wavelength is lost

• receptor doesn’t know the wavelength of light is has absorbed

T/F: rods are responsible for scotopic vision (dim light conditions)

True

Nocturnal animals have more what in the retina

concentration of rods

What is the tapetum lucidum

retroreflector of light behind the retina, increases light levels falling on retina often found in nocturnal animals

T/F: Dogs are trichromats?

False - Dichromats; similar to our S & L cones, resulting in color vision similar to human deuteranopia

Scotopic vision

Rods only (poor acuity)

Mesopic vision

Rods and cones

Photopic vision

Cones only (good acuity)

Simple lens eye

found in certain invertebrates like mollusks and annelids; basic structure that includes simple lens and photoreceptive tissue; small number of vertebrates with limited vision (cave dwelling fish) also have simple lens eyes

Simple corneal eye

les complex; found in certain invertebrates like arthropods (spiders); consists of a cornea and a photoreceptive layer

Compound eye

made of numerous small visual units each providing a portion of the overall image; typically found in insects (housefly)

Complex camera eye

found in humans and other vertebrate animals; consists of cornea, lens, and retina; lens and retina are more complex than that of the simple lens eye

Color Vision Deficiency

group of conditions that impacts how an individual perceives color; may be dichromat, monochromat or anomalous trichromacy

Dichromatism - Protanopia

Missing L cone, reg-green colorblindness

Dichromatism - Deuteranopia

Missing M - cone, red-green colorblindess

Dichromatism - Tritanopia

Missing S - cone, very rare

What is the most common category of color deficient vision

Anomalous Trichromacy

Anomalous Trichromacy

Impairment of color vision, not a loss; Cone variants come in variety of forms and may shift function up/down wavelength

Protanomaly

L cone affected

Deuteranomaly

M cone affected

Tritanomaly

S cone affected

What does the superior colliculus of the tectum do

receives visual signals from retina

Damage to what area can cause blindsight

V1 - Primary visual cortex

What do somatosensation receptors interpret?

Mechano (touch, pressure, stretch), Thermo (hot and cold temps), Noci (pain and intch), Proprio (awareness of body’s position, posture)

What is the main Human Cutaneous mechanoreceptor

Skin

Epidermis

outer layer of skin composed of stratified layers of flat cells sitting on columnar cells

Dermis

inner layer of skin composed of connective tissue, capillaries, nervous tissue, sweat glands, hair follicles

Hypodermis

deep layer of fat and connective tissue that insulates

Merkel Receptors

near surface, small receptive field; fire continuously; sense fine detail and shape

Meissner corpuscle

near surface, small receptive fields; fire only when stimulus is applied or removed; handgrip control, motion across skin

Ruffini cylinders

deeper, large receptive fields; respond continuously to stimulus, stretching of skin

Pacinian corpuscle

deeper, larger receptive fields; respond when stimulus is applied and removed; vibrations and texture

Where are C-FIber Low-Threshold Mechanoreceptors found

hairy skin

Details of C-LTMRs

• gentle, slow mechanical stimulation

• skin-neutral warmth

• pleasant, social touch

• insular cortex

Pheromones

chemicals emitted by one member of a species that triggers a consistent physiological or behavioral response in another member of the same species’ signals for chemical communication that may or may not have a smell

T/F: You must have a VO for pheromone use

False, it is not necessary (bees)

Releaser pheromones

triggers an immediate behavioral response amongst conspecifics (chemical released from bees telling other bees to attack)

Primer pheromones

triggers a physiological change among conspecifics that change behavior over prolonged exposure (female rodents housed together gradually come into estrus at same time)

Chemosignals or psuedo-pheromones

chemicals emitted by humans that are detected by olfactory system and have effect on mood, behavior, sexual arousal

Accessory olfactory bulb

neural structure found in some nonhuman animals; smaller than the main olfactory bulb; located behind main bulb

Order of food molecules

enter taste pores and interact with taste receptor cells in taste buds, which are housed in paillae

Taste pores

small opening at surface of a taste bud through which dissolved chemicals reach TRC

taste receptor cells

specialized sensory cell within a taste bud that detects particular chemical properties of substances and communicates info to nervous sys.

taste buds

cluster of specialized cells that detects chemicals associated with taste; each taste bud contains taste receptor cells and supporting cells

papillae

small anatomical structure on surface of tongue that can contain zero or many taste buds

Salty taste and receptor site

produced by ions like Na+, enters through ion channels = depolarization

Sour taste and receptor site

produced by acids through H+ ions, enter through ion channels = depolarization

Bitter taste and receptor site

associated with aversion, compounds such as quinine and caffeine; detected by G-protein coupled receptors

Sweet taste and receptor sites

sugars, glucose, fructose, aspartame; detected by G-protein coupled receptors

Umami taste and receptor sites

savory or brothy, produced by glutamate; detected by G-protein coupled receptors