Skin Physiology Flashcards
change sensory stimuli into nerve signals that are then conveyed to and processed in the CNS
sensory receptors
sensory receptors example
touch
sound
light
pain
cold and warmth
can cause either an immediate reaction or can be stored
sensory receptors
activities in this system are initiated by sensory experience exciting sensory receptors
nervous system
receptor for mechanical stress or strain
mechanoreceptors
receptor for temperature
thermoreceptors
receptor for damage or threat of damage to body tissues
nociceptors
receptors for visible light
photoreceptors
sense of position receptor
proprioceptors
chemical receptor
chemoreceptor
blood vessel pressure receptors
baroreceptors
humidity receptors
hydroreceptors
electrofields receptors
electroreceptors
osmolarity of fluids receptors
osmoreceptors
infrared radiation receptions
infrared receptors
uv radiation receptors
ultraviolet receptors
significant as it prevents the nervous system from being bombarded with information about insignificant matters
adaptation
sensory receptors adapt either ___ or ____ to any constantly occuring stimulus after a period of time
partially
completely
sensory receptor that adapts slowly to a stimulu
tonic receptor
sensory receptor that adopts rapidly to a stimulus
phasic receptor
classification of receptors based on location
exteroreceptors
interoreceptors
cutaneous
deep
Any receptor that detects external stimuli.
exteroreceptors
examples are the thermoreceptors in the skin, which monitor the temperature of the external environment.
exteroreceptors
re molecular sensors or receptors in neurons that directly detect various interoceptive signals, and transduce them into electrical, hormonal, or other non-neural signals to be integrated and interpreted by the brain.
interoceptors
skin tactile sensibilities in the epidermis and dermis
what kind of receptor
mechanoreceptors
example of mechano receptors in epidermis and dermis
Merkel’s disks
Meissner’s corpuscles
example of deep tissue sensibilities receptors
Ruffini’s endings
Pacinian corpuscles
a main type of tactile end organ highly abundant in human fingertips, whisker hair follicles, touch domes and other tactile-sensitive spots throughout mammalian bodies
merkel disc
consist of a cutaneous nerve ending responsible for transmitting the sensations of fine, discriminative touch and vibration.
meissner corpuscles
slow adapting, encapsulated receptors that respond to skin stretch and are present in both the glabrous and hairy skin. -
ruffini endings
an encapsulated ending of a sensory nerve that acts as a receptor for pressure and vibration.
pacinian corpuscle
thermoreceptors (2)
cold receptors
warm receptors
receptors from 5 to 35 degrees celsius
cold receptors
receptors from 30 to 45
warm receptors
sensory fibers that respond to stimuli that are potentially damaging to the organism.
nociceptors
free nerve endings can be (2)
myelinated
unmyelinated
slowly-adapting small receptive fields
a. merkel’s dics
b. ruffini’s ending
c. meissner’s corpuscle
d. pacinian corpuscle
merkel’s disc
rapidly adapting, small receptive fields
a. merkel’s dics
b. ruffini’s ending
c. meissner’s corpuscle
d. pacinian corpuscle
meissner’s corpuscle
slowly adapting, large receptive fields
a. merkel’s dics
b. ruffini’s ending
c. meissner’s corpuscle
d. pacinian corpuscle
ruffini’s ending
large receptive, rapidly adapting
a. merkel’s dics
b. ruffini’s ending
c. meissner’s corpuscle
d. pacinian corpuscle
pacinian corpuscle
free nerve endings characterize what receptors (2)
nociceptors
thermoreceptors
consist of remaining types of cutaneous receptors
encapsulated receptors
exist for specialized functioning
encapsulation
location of two point sensibility
back of neck
fingertip
forearm
tip of nose
palm of hand
tongue
upper arm
thigh area
leg area
areas of the body having many touch receptors that have a finer sense of “feel” or tactile discrimination
fingers
representation of the human body with proportions determined by cortical representation of distinct body areas
homunculus
will show a short burst of action potentials when the stimulus is first applied on the skin, but then they will cease firing despite the continuous application of the rod
slow adapting (SA) fibers
receptors involved in what adapt slowly
proprioception
start firing action potentials (or increase) their firing rate at the onset of the stimulus and continue to fire until the stimulus ends
rapid adapting (RA) fibers
receptors involved in light touch are what kind of fibers
rate of adaptation
rapid adapting fibers
region of skin from which stimuli can evoke a response
receptive fields
two types of receptive fields
type 1
type 2
have small receptive fields with well-defined borders (ex. glabrous or hairless skin)
type 1 units
have wider receptive fields with poorly defined borders and only a single point of maximal sensitivity, from which there is a gradual reduction in sensitivity with distance
type 2 units
shortest distances between two points that can be felt like two points
two point tresholds
study two point touch tresholds
+1
tactile localization include
plam
fingertips
forearm (dorsal and ventral)
lips
thigh region
what area should serve with neurons that have small receptive fields
high tactile acuity
varies with location although touch sense is easily localized
tactile acuity
generally, the greater the neural representation of a bodily area, the less likely are _____ ____
localization errors
describes the ability of the subject’s senses to feel the pressure made by placing coins inside the antecubital fossa
touch receptors adaptation
the time of pressure sensation ntil it was no longer felt was recorded
what kind of sensation assessment
touch receptor adaptation
free nerve endings that wrap around the bases of hair follicles.
Peritrichial nerve endings
hair receptors that monitor the moevment of hairs
peritrichial endings
what part of the subject were applied with increasing weight in sensation intensity difference
distal phalanges
significant to determine the discrimination threshold of the subject or to identify whether he can tell apart, or discriminate, two things that differ by only a slight addition of weight
Weber’s law
the smallest detectable addition of weight aboev whatever the initial intensity was
discrimination threshold
a subject cannot easily tell whether one stimulus felt twice, half, or three-quarters as strong as nother
weber’s law
gradations of stimulus strength are discriminated and approximately in proportion to the
logarithm of stimulus strength
proportional to equal addition of sensation
equal relative addition
subject was asked to dip each of her hands in two beakers with cold and warm water
temperature adaptation
factors that affect temperature adaptation
-subject’s body temperature
-number and density of thermoreceptors in the skin
maintains a nearly constant body temp which is usually higher than the temp in the environment
human body
considered as slowly adapting
cold thermoreceptor
strange phenomenon of perception of pain in one area of the body when another is actually receiving the painful stimulus
referred pain
happens when afferent-pain conducting fibers from the site of pain converge with afferent-pain conducting fibers of another area on one central neuron
referred pain
reffered happens when afferent-pain conducting fibers from the site of pain converge with afferent-pain conducting fibers of another area on one central neuron of what tract
paleospinothalamic
impulses from the site of pain travel in the same central pathway of another area to reach the same final sensory neuron in the ___
brain
significant in the initial evolution of patients for proper diagnosis and treatment
referred pain
Largest organ in the body.
skin
” is what gives our brains a wealth of information about the natural environment, including temperature, humidity, and air pressure
sense of touch
layer of the skin with dead skin cells, produce melanin, contain touch receptors
epidermis
layer of the skin with hair follicle, blood vessels, skin glands, nerve endings
dermis
layer of skin with insulator and energy reserve
subcutaneous tissue
Responsible for all the sensations we feel – cold, hot, smooth, rough, pressure, tickle, itch, pain, vibrations, and more
somatosensory system
somatosensory system has four main types of receptors
Mechanoreceptors
Thermoreceptors
Pain receptors
Proprioceptors
These receptors perceive sensations such as pressure (indentions), vibrations, and texture
mechanoreceptors
four types of mechanoreceptors
merkel’s disks
meissner’s corpuscles
ruffini’s corpuscles
pacinian corpuscles
Found in the very top layers of the dermis and epidermis (2)
merkel’s disks and Meissner’s corpuscles
Generally found in non-hairy skin such as the palms, lips, tongue, soles of feet, fingertips, eyelids, and the face
Merkel’s disks and Meissner’s corpuscles
These are rapidly adapting receptors that can perceive when you are touching something and how long the object is touching the skin. (2)
merkel’s disks
meissner’s corpuscles
Located deeper in the dermis and along joints, tendons, and muscles (2)
ruffini’s corpuscles and ruffinian
Can feel sensations such as vibrations traveling down bones and tendons, rotational movement of limbs, and the stretching of skin.
ruffini’s corpuscles and ruffinian
Greatly aids the ability to do physical activities (Ex. walking and playing ball).
ruffini’s corpuscles and pacinian corpsucles
These receptors perceive sensations related to the temperature of objects the skin feels.
thermoreceptors
Found in the dermis layer of the skin, and is categorized as hot and cold receptors.
thermoreceptors
The highest concentration of thermoreceptors can be found in the (2)
face
ears
Also known as the Nocireceptor.
pain receptors
Receptors that detects pain or stimuli that can or does cause damage to the skin and other tissues of the body.
nocireceptor
pain receptors Detect pain that is caused by 3 stimuli
mechanical stimuli
thermal stimuli
chemical stimuli
These receptors cause a feeling of sharp pain to encourage you to quickly move away from a harmful stimulus.
pain receptors
These receptors functions with the sense the position of the different parts of the body in relation to each other and the surrounding environment.
p
proprioreceptors
Found in tendons, muscles, and joint capsules (this location in the body allows these special cells to detect changes in muscle length and muscle tension).
proprioceptors
