78 terms

chapter 11: the senses

essentials of A&P
special senses
sight, sound and balance, taste, and smell
general senses
sensations of heat, cold, pain, nausia, hunger, thirst and the need to urinate and deficate
cutaneous senses
sensations of touch, heat, cold, and pain on the skin
visceral senses
sensations of nausea, hunger, thirst, and the need to urinate and deficate
extrasensory perception (ESP)
senses outside the normal sensory perceptions; reading minds, intuition
small opening in the eye that allows light to pass through where it goes to the lens
the inner most layer of the eye that focuses the light rays; it is a delicate membrane that continues posteriorly and joins the optic nerve; contains the rods and cones
part of the eye that constricts or dilates allowing more or less light in to focus
cone shaped cavity formed by the skull that houses and protects the eyeball
protective membrane that lines the exposed surface of the eyeball and acts as a protective covering for the exposed eye surface
lacrimal apparatus
produces and stores tears which act as an aniceptic
lacrimal gland
corresponding ducts or passageways that transport tears
the "fluids of the eye"
aqueous humor
bathes the iris, pupil, and lens and fills the anterior and posterior chambers of the eye
vitreous humor
clear, jellylike fluid that occupies the entire eye cavity behind the lens
the outermost layer of the eye that is a tough, fibrous tissue that serves as the protective shield we commonly call the "whites of the eyes", it also contains the cornea
structure of the eye that bends light waves to focus them on the surface of the retina
the middle layer of the eye that is highly vascularized and is also a pigmented region that provides nourishment to the eye; it also contains the iris and the pupil
ciliary muscles
muscles that can alter the shape of the lens, making it thinner or thicker to allow the incoming light rays to focus on the retinal area
combining the action of changing the size of the pupil and the lense curvature to make sure the image converges in the same place on the retina, and therefore is properly focused
globe-shaped organ of vision
active in dim light, and do not perceive color
active in bright light, and do not perceive color
cause a chemical change when light hits them, this chemical change causes an impulse to be sent to the optic nerve and then the brain where the impulse is interpereted and we "see" the object
conjunctival hemorrhage
blood vessels in the conjunctiva to rupture; this can be caused by trauma, sneezing, coughing, vomiting, straining, and high blood pressure
unequal pupils, 20% of the population have some degree of this
pupillary constriction
controlled by the oculomotor nerve (CN III)
an unvoluntary jittery movement of the eyes, usually involves both eyes and is often exaggerated by looking in a particular direction; used in field sobriety tests; can be caused by alcohol, or medication
physicians who specialize in the medical and surgical management of eye disorders
doctors of optometry who perform refractive exams and prescribe glasses and contact lenses
corneal abrasions
scrape of cut on the surface of the corena; commonly caused by contact lens misuse or trauma.
Hemorrhage into the anterior chamber of the eye. Both eyes are patched, bed rest to prevent increase in intraocular pressure & allow for reabsorption of blood in the anterior chamber.
ultraviolet keratitis
severe pain, tearing, light sensitivity, and foreign body sensation that occurs from 6-12 hours after the occular exposure to a welding arc, tanning lights, or bright snow.
acute angle-closure glaucoma
a serious medical emergency, patient often complains of cloudy vision, eye ache, headache, and frequently nausea and vomiting.
eye disorder characterized by optic nerve damage usually caused by the abnormal increase of intraocular pressure, cant use peripheral vision
responsible for hearing and balance; senses vibrations in the air and translating them into an interpretable sound via the eight cranial nerve
pinna (auricle)
collects and directs sound waves into the auditory canal
secreted by the ceruminous glands to lubricate and protect the ear
ceruminous glands
secrete cerumen (ear wax)
auditory canal (external auditory meatus)
contains earwax and houses the ceruminous glands, and the eardrum
tympanic membrane
the eardrum; where the external ear ends and the middle ear begins
tympanic cavity
middle ear; basically a space that contains the three smallest bones of the body (ossicles)
oval window
begins the internal ear and carries the amplified vibrations from the tympanic ossicles; the sound can be amplified as much as 22 times their original level
eustachian tubes
connect pharynx to ears, connect to the middle ear and equalize pressure
inner ear; comprises three seperate, hollow bony spaces that form a complex maze of winding and twisting channels
vestibule chamber
another name for the three areas of the labyrinth, houses the internal ear, cochlea, and the semicircular canals
the bony spiral or snail shell-shaped entrance to the inner ear connected to the oval windown membrane; contains perilymph
fluid in the cochlea that helps transmit the sound through that area to the endolymph
fluid at the back of the labyrinth that carries the sound through tiny hairlike receptors that are stimulated and conduct the signal to the brain via the vestibulocochlear nerve
conductive hearing loss
hearing loss caused by interference with sound transmission in the external auditory canal, middle ear, or ossicles
rinne's test
teast for deafness using a tuning fork placed on the auditory opening of the ear. When the patient ceases to hear the ringing it is placed on the bony area below.
sensorineural loss
hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness.
gustatory sense
sense of taste
bumps on the tongue that contain several taste receptors
the taste sensation produced by glutamate; identifies the presence of amino acids in foods
tactile corpuscles
touch receptors; small rounded bodies located in the skin and especially concentrated at the fingertips; also located on the tip of the tongue
sensory receptors on the skin/ tongue adjust to get used to the temperature (after the 100+ degree summer 89 degrees feels cool outside)
gustatory sense
the sense of taste
medications that help aleviate pain
referred pain
originates in an internal organ yet is felt in another region of the skin
phantom pain
can result from an amputated limb: individual can feel pain or sensations in an arm or leg he or she no longer has
inflammation of the membrane that lines the eye; can either be acute or chronic and is caused by a variety of irritants and pathogens; acute phase commonly called pink eye
condition in which the lens loses its flexibility and transparency and light cannot easily pass through the clouded lense; untreated it can lead to blindness; can be sped up by exposure to sunlight, and is also caused by age
farsightedness; occurs when the eye cannot focus properly on nearby objects; results from the flattening of the globe of the eye or a refraction problem where light rays focus behind the retina
farsightedness; occurs with age, usually between 40 and 45 years; the lens becomes stiff and yellowish, this can make it difficult for the adult to focus, and make them sensitive to glare, which can impair nighttime driving abilities
nearsightedness; causes an object at a distance to appear blurred
lazy eye; usually occurs in childhood; poor vision in one eye is caused by the abnormal dominance of the other eye
Rapid eye movement (REM)
stage of sleep is measured during sleep studies and helps to diagnose sleep disorders
otitis media
an infection of the middle ear usually caused by bacteris or virus; frequently in infants and young children
upper respiratory infection (URI)
a cold
inflammation of the inner ear and usually caused by high fevers; it can cause vertigo
feeling of dizziness or whirling in space
meniere's disease
chronic condition that affects the labyrinth and leads to progressive hearing loss and vertigo
either partial or complete; and is caused by a variety of conditions ranging from inflammation, and scarring of the tympanic membrane to the auditory nerve and brain damage
a ringing sound in the ears which according to superstition, means someone is talking about you