6A: Anatomy of sensory perception Flashcards
CONES:
a) Detection type
b) Sensitivity ( function best in)
c) Location
d) Recovery time
a) Color
b) Low ( Function best in bright light)
c) Macula and Fovea
d) Fast
Rods:
a) Detection type
b) Sensitivity ( function best in)
c) Location
d) Recovery time
a) Black and white
b) High ( function even in dim light)
c) Peripheral of the retina
d) Slow
Rhodopsin
Light sensitive receptor protein contained in Rods
Photopsin
Light sensitive receptor protein contained in Cones
Retina
Binds to opsin protein, rearrange go from cis to trans retinal upon light exposure
Transducin
Protein in rods and cones
Attached to rhodopsin until exposed to light, upon which it detaches and becomes active
Visual field summary: Central( Fovea) a) High density b) Light condition c) Perception d) Light sentivity acuity
a) Cones
b) Bright
c) Color and detail perception
d) Low/ High acuity
Visual field summary: Peripheral a) High density b) Light condition c) Perception d) Light sentivity acuity
a) Rods
b) Dim
c) Motion
d) High/ Low
Which organ in the vestibular system detects angular acceleration
Semicircular canal filled with endolymph –> Rotation causes endolymph to shift within canals
Which organ in the vestibular system detects linear acceleration and head?
Otolith organs (utricle and saccule) detects- hair cell with calcium crystal
Causes of dizziness and vertigo
endolymph continues to move briefly after cessation of movement
Eye anatomy: Cornea
a transparent layer of eyes: refract incoming light
Eye anatomy: Iris
a) Control
b) Divide the front of the eye into
c) Contain which muscle
The colored part of the eye- thin circular structure that
controls the diameter of the pupil ( amount of light reaching the retina
b) Anterior and Posterior
c) Dilator and Constrictor
Eye anatomy: Lens
Assisting the cornea in refracting light to be focused on retina
Eye anatomy: Aqueous humour
a) Produced by which cell
b) Fill what of the eyes
a) Ciliary epithelium
b) anterior and posterior chambers of the eyes
Eye anatomy: Vitreous humour
a) Produced by which cell
b) Fill what of the eyes
a) ciliary body
b) Vitreous body ( the space between lens and retina)
Eye anatomy: Conjunctiva
Tissue that lines the inside of the eyelids and covers the sclera
Eye anatomy: Sclera
Opaque, fibrous, outer layer of eye that is white
Eye anatomy: Suspensory ligaments
Connects the ciliary body with the crystalline lens of the eye
Eye anatomy: Retina
The innermost tissue within the eye, sensitive to light
Eye anatomy: Macula
Oval-shaped pigmented area near the center of the retina
Responsible for central, high-resolution, color vision
Eye anatomy: Fovea
Small, central part of the macula containing only cones
Responsible for visual detail
Eye anatomy: Choroid
Vascular layer of eye between the retina and sclera
Eye: Phototransduction cascade
Light in the eyes–> Rods and Cones–> Optic nerve–> Optic Chiasm–> Optic tract–> Lateral Geniculate nucleus–> Visual cortex
Visual mapping in the brain
Due to Optic Chiasm, right visual field is received by the left side of the brain
Trichromatic theory of color vision
Color vision is receptive to 3 different types of photoreceptor: Red, green, and blue
Opponent process theory of color vision
Color information from cones is combined such that we perceive three opposing pairs
Black/White
Blue/ Yellow
Red/ Green
Color is detected by?
CONE
Form is detected by which pathway
Detection by Parvocellular pathway, which is responsible for perception of finer detail, such as form and color
Motion is detected by which pathway
Detection by Magnocellular pathway, which is responsible for perception of coarses detail, such as depth and motion
What is parallel processing?
Ability of the brain to simultaneously process various components (e.g. color, motion) of a visual stimulus, allowing the brain to divide stimuli into four features - color, motion, shape, and depth/distance
Component of the outer ear?
Pinna (auricle), external auditory canal, tympanic membrane
Component of the middle ear?
Connected to nasopharynx via Eustachian tube
Contains ossicles
Ossicle
Malleus, incus, and stapes
Footplate of stapes rests in oval window of cochlea
Component of the inner ear?
Contains bony labyrinth and membranous labyrinth
Responsible for sound detection and balance
Inner ear anatomy: Bony labyrinth
Filled with perilymph
Comprised of three components: vestibule of the ear, semicircular canals, and the cochlea
Membranous labyrinth
Contained within the bony labyrinth. Consists of the utricle and saccule, two membranous sacs, plus ducts within the cochlea and semicircular canal
Ducts are filled with endolymph
Cochlea
Translates vibrations into neural impulses
Sends signals to the auditory nerve which transmits to the medial geniculate nucleus
Organ of corti
Located within the cochlea and contains hair cells
Semicircular canals
Main function is to regulate balance
Part of the vestibular system
Auditory pathway (distal)
Outer ear (pinna, external auditory canal, tympanic membrane) → middle ear (ossicles) → inner ear (cochlea, semicircular canals, utricle/saccule → auditory nerve
Auditory pathway (proximal)
Auditory nerve (part of vestibulocochlear nerve) → medial geniculate nucleus (MGN) → auditory cortex
Superior olive
Function is to localize sound
Located in the brain stem
Inferior colliculus
Function is startle reflex
Component of vestibulo-ocular reflex, which keeps eyes fixed on single point as head rotates
Place theory
Theory that the perception of different pitches is due to various frequencies activating different portions of the cochlea basilar membrane
Hair cells at the base of the basilar membrane are activated by high frequency sounds, whereas hair cells at the apex are activates by low frequency sounds
Basilar tuning
Place theory in practice, whereby hair cells in the cochlea are preferentially activated at specific frequencies, allowing the brain to distinguish between high and low frequency sounds
Hair cells at base of cochlea are activated by high frequency sounds
Hair cells at apex of cochlea are activated by low frequency sounds
Primary auditory cortex
Brain region that processes auditory information
Located within the temporal lobe
Tonotopical mapping
Neurons within the auditory cortex are organized according to the frequency of sound to which they respond best
Pheromone
Chemical signal that triggers an innate response in members of the same species
Anosmia
Inability to perceive odor
Vibrational theory of olfaction
Vibrational frequency of a molecule is responsible for its specific odor profile
Steric theory of olfaction
Also known as shape theory, this asserts that odorous molecules fit into receptors similar to a lock-and-key mechanism
Olfactory epithelium
Specialized epithelium inside nasal cavity that contains olfactory receptor neurons
Olfactory bulb
Specialized region of brain that receives sensations of smell
Input = olfactory receptor neurons of olfactory epithelium
Olfactory bulb projections
Olfactory bulb projects directly to the amygdala and hippocampus
Unlike other senses, olfaction bypasses the thalamus
Cribiform plate
Portion of ethmoid bone with small holes called the olfactory foramina, allowing passage of the olfactory nerves
Olfactory bulb sits atop the cribriform plate
Taste bud
Contain gustatory cells
Provides for detection of all 5 tastes anywhere on the tongue
Types of taste buds
Three types of taste buds. Mnemonic: Fun in the front = fungiform, foliage on the sides = foliate, Circle around the back = circumvallate Fungiform papillae (anterior) Foliate papillae (side) Circumvallate papillae (posterior)
Filiform papillae
Do not contain taste buds
Located all over tongue, most densely at the center of the tongue, accounting for the lack of taste sensation in this region
Nerve innervation
Anterior 2/3 of tongue sends taste signals via the VII cranial nerve
Posterior 1/3 of tongue via the IX (glossopharyngeal) and X (vagus) cranial nerves
GPCR receptors
Utilized in sweet, umami, and bitter taste profiles
Ion Channels
Utilized in salty and sour taste profiles
