Touch
Difference of interoception, exteroception, and proprioception
interoception - internal organs
exteroception - things on the body's surface
proprioception - positioning of muscles and joints/sense of where we are in space
Explain what happens if the temperature is inside or outside of the ranges of warm and cold receptors
Inside - sensory adaptation will happen rapidly
Why do old people lose their sense of smell and taste
Olfactory receptors are exposed to the environment which makes it easy for them to get damaged. They are regenerated slower than they are damaged as we age.
You take off in an airplane and notice your ear begin to hurt more and more as the plan flies higher. Explain why this is happening and how to fix this.
Their air pressure is getting lower than the air pressure of your inner ear as you raise off the ground. This cause the air in your ear to push outward on your tympanic membrane. To equalize the pressure you must yawn or chew to open the auditory tube that connects to the throat
List and describe the outer three layers of the eye(not the front part)
sclera - dense fibrous connective tissue with lots of collagen, white part of the eye
choroid coat - dark, contains melanocytes - make melanin
retina - contains photoreceptors
Explain the difference of sensation, perception, and projection
Sensation is the vague sense of a sound or image, perception is the processing and understanding of the brain of this sensation. Projection is the brain determining the origin of sensation, such as where you are feeling pain
Where do impulses of nociceptors go, and explain each region
diencephalon - relay system to get info where it needs to go
reticular formation - "will not feel pain until impulse reaches here" - sensation of pain?
cerebral cortex - projection takes place here
limbic system - emotional response to pain
What makes up the taste bud?
taste cell, supporting cells, taste hairs
Frequency of the sound waves is the pitch. Different regions of hair cells will be stimulated by different pitches.
The frequency of action potentials will be the volume that you perceive.
What happens if there is a break in a membrane that causes endolymph and perilymph to combine?
Perilymph is high in sodium and low in potassium. Endolymph is high in potassium and low in sodium. When they mix, this will ruin the concentration gradients of these ions. This will make it very difficult for an action potential to happen, leading to bad hearing/hearing loss
Not being able to hear a certain pitch means certain receptors are damaged.
Explain sensory adaptation
Due to continuous stimulation, the receptors decrease the frequency of action potentials or completely fail to reach threshold, or less neurotransmitter is released
Ex. getting used to the temp of pool water or the clothes you are wearing
Central adaptation is this in the brain and spinal cord, peripheral adaptation is when this happens anywhere else.
What are natural analgesics, what do they do, and why?
They reduce frequencies of impulses, this is necessary because nociceptors do not do much sensory adaptation.
Enkaphalins and serotonin - released in dorsal horn
endorphins - in pituitary glands and hypothalamus
What is the nerve pathway for taste?
Facial, glossopharyngeal, and vagus nerves take information to the gustatory cortex in parietal lobe.
Why does the sound impulse always travel to both temporal lobes
Sound localization in the auditory cortex
Young I-pad kid Bohden is constantly on his I-pad playing clash of clans or taking stats at a baseball game. Explain how this could effect his eye over time.
Constantly looking at something close up means Bohden's lens will be rounded more often. When the lens is rounded, it takes up more space. This will increase the pressure inside the eye. The eye may expand a little due to this, which can cause myopia.
LASIK changes the shape of the cornea to adjust to the person's eye (more convex for hyperopia, less convex for myopia)
If I poke you with a fork on the hand and on the thigh, explain why you might feel 4 different touches on the hand but only one touch on the thing
Higher amount of tactile corpuscles on the hand, therefore 4 tactile corpuscles will be stimulated. On the thigh, only one tactile corpuscle will be stimulated.
Free nerve ending feel very light touch such as itching and extend through the stratum basale and spinous. Lamalleted corpuscles respond to deep pressure, vibrations, stretch
Explain proprioception reflexes
Muscle spindles - Too much stretch = contract
Golgi tendon organ - too much tension=relax
Explain the process from sound wave to brain.
Sound waves are funneled in by the auricle and travel through the external acoustic meatus to the tympanic membrane. This causes the tympanic membrane to vibrate the malleus, which vibrates the incus, which vibrates the stapes, which pushes in on the oval window. This pushes the perilymph in the Scala vestibule which travels into the Scala tympani. This vibration causes the specific hair cells for the pitch of the sound wave that are attached to the basilar membrane to push up against the tectorial plate, which sends an impulse. The cochlear branch of the vestibulocochlear branch takes this to the auditory cortex of both temporal lobes
What are the three types of deafness and the differences of them
Conductive deafness - something is blocking the sound wave or damage to the physical parts of ear(not neurons)
sensorineural deafness - something is wrong in the neural pathway of sound
inattention deafness - too focused on something else
Explain the path that light goes through for you to see
Cornea -> aqueous humor -> lens -> vitreous humor -> retina -> photoreceptors -> optic nerve -> crossing over at optic chiasma -> visual cortex of occipital lobes
How does referred pain happen?
Due to common nerve pathways, the cerebral cortex may project visceral pain onto an area more peripheral such as the skin
Explain the pathway of a smell reaching the brain
Cilia on ends of the cilia bipolar neurons bind with a chemical(chemoreceptor) and the olfactory receptor cells go through holes in the cribriform plate. They communicate with the olfactory nerve, which goes through the ethmoid bone, into the olfactory core and limbic system
Different molecules are sensed by different types of nerves. These combinations make us able to smell a variety of odors. (Olfactory code)
Explain both ways the ear is protected from loud sounds.
The tympanic reflex is when the tensor tympani and the stapedius muscles contract to lower the amount of vibration to soften the sound.
The tectorial membrane helps the bending hair cells to not be damaged.
What organs are being used for each of static and dynamic equilibrium and explain both types of equilibrium?
Static equilibrium - utricle(forward and backward) and saccule(up and down) -
Dynamic - semicircular canals (posterior, anterior, and lateral) - spinning motion
at the ampulla of the semicircular canals, there is a crust ampullaris contain a gelatinous cupula
Explain why you see best at the fovea centrals in the macula lutea
Light directly hits photoreceptors. High density of cones in macula lutea and density of cones slowly decreases outward