Chapter 13: The body senses Flashcards
what is tactile perception
tactile perception is touch. It is perception of the mechanical stimulation or deformation of the skin
what senses are covered in this chapter?
tactile perception, Proprioception, nociception (pain) Thermoreception, Haptic perception, and vestibular for balance and acceleration perception
what are the two types of skin
hairy skin ex: on head and forearms glabrous skin (hairless) ex: on lips and palms
what are the two layers of skin?
Epidermis (outermost surface)
dermis
In general what are Mechanoreceptors?
mechanoreceptors are sensory receptors that transduce mechanical deformations of skin into neural signals that are sent to the brain
what are the 4 main types of mechanoreceptors? and how do they differ
mechanorecepter types differ in the timing of their response.
slow adapting mechanoreceptors =
SAI and SAII
-these produce a burst of action potentials at the onset of skin deformation but a lower and sustained response until the stimulus is removed
Fast Adapting mechanoreceptors=
FAI and FAII
-these produce burst of action potentials only at onset and offset of deformation.
what are the specialized ending types of the main mechanoreceptors?
merkel cells
meissner corpuscles
pacinian corpuscles
merkel cells
are the specialized endings of SAI mechanoreceptors where transduction takes place
meissner corpuscles
are specialized endings of FAI mechanoreceptors where transduction takes place
pacinian corpuscles
are the specialized endings of FAII mechanoreceptors where transduction takes place
SAI mechanoreceptors
these are slow adapting mechanoreceptors with merkel cell endings.
SAI’s have reletively small receptive fields and they are arranged relatively densely near the surface of the skin (upper dermis)
SAII mechanoreceptors
these are slow adapting mechanorecptors
they have relatively large receptive fields and are distributed within the skin relatively sparse and deep
dermis
FAI mechanoreceptors
these are fast adapting mechanoreceptors with meissner corpuscle endings
relatively small receptive fields
densely arranged near skin surface
FAII mechanoreceptors
fast adapting mechanoreceptors with pacinian corpuscle endings
large receptive fields
sparsely distributed deep in the skin
which skin deformations do each mechanoreceptor type respond most strongly to
SAI mechanoreceptors with merkel cell endings respond strongest to indentation by edges, curves, and textures
