Cutaneous Mechanoreceptors

Question 1

Hair follicles

Answer 1

Arrays of nerve fibers surrounding follicles; Located in epidermis and dermis

Function: Senses displacement of hair, detect velocity and direction of movement across skin

Question 2

Meissner’s corpuscle

Answer 2

Found in glabrous skin (fingertips, lips, where there is good tactile discrimination)

Function: Two-point discrimination, precise location, tapping, flutter (touch & vibration). Have encapsulated receptors with low threshold, rapidly adapting.

Question 3

Merkel’s receptor

Answer 3

Slowly adapting in glabrous skin (dermis or deep epidermis) Not encapsulated

Function: Detect vertical indentations of skin and response is proportional to stimulus intensity

Question 4

Pacinian corpuscles

Answer 4

Hairy & non-hairy skin found deep in the dermis

Function: Encode vibration; fastest adapting mechanoreceptor

Question 5

Ruffini corpuscle

Answer 5

Dermis of hairy and non-hairy skin and in joint capsules

Function: Stimulated when skin is stretched; slowly adapting receptors; detect stretch and joint rotation

Question 6

CN VII (geniculate ganglion)

Answer 6

Cutaneous sensation from back of ear and external auditory meatus

Question 7

CN IX (superior ganglion)

Answer 7

Somatosensory afferents from tympanic membrane, skin of external ear and posterior third of tongue

Question 8

CN X (superior ganglion)

Answer 8

Somatosensory inputs from skin of back of ear and external auditory meatus