Sensory Perception

Synesthesia

a perceptual phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway

Somatic (general) Senses

receptors found throughout the body including joints and organs

Special Senses

specialized receptors found in the head (sight, smell, sound, taste)

Sensation

feeling that occurs when a brain interprets a sensory nerve impulse

Projection

the brain causes a feeling to stem from a source

Sensory adaptation

sensory receptors stop sending signals when they are repeatedly stimulated

Receptor cells in the PNS are activated by …

stimuli in the environment

What are the three different criterias for receptor cells?

cell type, position, function

Free nerve endings

dendrites embedded in tissue as receivers which respond to pain and temperature

Encapsulated

embedded in connective tissue to increase sensitivity (pressure and touch)

Specialized

receptors in the retina of the eye

Exteroceptor

located near external environment (skin)

Interoceptor

interprets stimuli from internal organs

Proprioceptor

located near moving body parts, interprets position

Chemoreceptor

chemicals, mostly found in nose/mouth

Photoreceptor

light

Osmoreceptor

respond to solutes in body fluids

Thermoreceptor

temperature

Mechanoreceptor

pressure, vibration, body position, movement

Visceral pain

occurs in visceral tissues such as heart, lungs, intestine

Referred pain

feels as though it is coming from a different part

Acute pain

originates from skin, usually stops when stimulus stops

Chronic pain

dull aching pain

FLACC

Face, Legs, Activity, Cry, Consolability Scale

Overview of how opioids work

nerve sends signals

opioids slow/block signal

limbic system (emotional) and reward pathway are stimulated

Special Senses

Olfactory, Gustatory, Hearing and Equilibrium

Olfactory

odor

receptor cell

olfactory bulb

olfactory tract

Gustatory

papillae (taste buds)

Taste sensations

sweet

salty

bitter

sour

savory

Umami

A savory taste →mixture of 2 or more tatse

Genetics play a role in

whether you like certain foods

Auricle (pinna)

outer ear

Auditory canal

ear canal

Auriculares

responsible for ear movement

Ear wiggling is considered

vestigial trait

Vestigial Trait

a trait that no longer functions but is part of our evolutionary past

Middle ear

tympanic cavity

Eardrum

tympanum

Auditory Ossicles

malleus, incus, stapes

The malleus, incus, and stapes transmit …

vibrations and amplify the signal

Auditory Tube (Eustachian tube)

connects the middle ear to the throat →helps maintain air pressure

Labyrinth

communicating chambers and tubes

Semicircular canals

sense of equilibrium

Cochlea

snail shaped, sense of hearing

Organ of Corti

contains hearing receptors, hair cells detect vibrations

Loud noises can damage the …

hair cells located in the cochlea

Tinnitus

ringing in the ear

Static equilibrum

maintain stability and posture

Dynamic equilibrum

balance during sudden movement

Cerebellum

interprets impulses from the semicircular canals and maintains overall balance

Otolaryngology

study of ear, nose, and throat

Anosmia

no smell

Anhidrosis

inability to sweat

Congenital Analgesia (CIP)

feel no pain

Syndrome

disease that has more than one feature or symptom

Usher syndrome can also cause …

vision problems

Deafness can also be caused by …

prenatal infections

Prenatal infections

toxoplasmosis

rubella

cytomegalovirus

herpes

Postnatal infections

meningitis

streptococcus

influenza

listeria

Prebycusis

age related hearing loss

Eyelid

covers and protects the eye, thin skin will not protect you from intense radiation

Eyelashes

fine hair that function to protect the eyes from dust and debris

Trichiasis

inversion of the eyelashes, which can irritate the eye

Conjunctiva

a covering around the eye and under the eyelids

Pink eye

conjunctivitis

Extrinsic eye muscles

superior rectus - inferior rectus

medial rectus - later rectus

superior oblique - inferior oblique

Lacrimal glands

produce tears, which drain into the nasal cavity via the lacrimal duct

Tears function to …

moisten and lubricate the eye surface, and it has enzymes that kill bacteria

Cornea

transparent dome that focuses light

Sclera

continuation of cornea, going toward the back of the eye (white part)

Optic nerve

exits at optic disk and transmits information from the eye to occipital lobe of the brain

Optic neuritis

sudden vision loss

Choroid

contains blood vessels

Ciliary body

holds the lens in place

Lens

focusing

Iris

colored portion of the eye

Pupil

opening for light to enter

Aqueous humor

liquid surrounding the lens

Melanin

browish pigment that adds color to your hair, eyes, and skin

Heterochromia

one eye is a different color than the other

Pupils

dilate or constrict to adjust light entering eye

Red eye

light reflecting off the retina

Retina

visual receptor cells

Fovea centralis

region of the sharpest vision, also called macula

Optic disk

where nerve fibers leave eye creating a blind spot

Vitreous humor

supports internal parts, fluid within the eye

Blind spot

the region where the optic nerve and bloods vessels meet. Has no photoreceptors

Photoreceptors in the retina are

sensors for light

Rods

monochromatic (black and white)

Cones

color vision

Accommodation

lens change shape to facilitate focusing

Images are projected to the back of the eye and then …

the lens reverses the image

Zonules of Zinn

connect ciliary body to lens

can change the shape of the lens

also called suspensory ligament

Cataracts

clouding of the eye

Aniridia

a condition where a person is born without an iris

Onchocerciasis

river blindness →disease caused by infection by a parasitic worm

Color blindness

genetic trait that effect boys more than girls

Floaters

occur when the vitreous substance clumps and casts shadows on the retina

Retinsl detachment

occurs ehrn the retina is pulled away from its normal position

Glaucoma

pressure from vitreous humor damages the optic nerve and can lead to blindness