Somatosensory System

Question 1

sensations relating to the body’s superficial and deep parts as contrasted to specialized senses such as sight

Answer 1

somatosensory

Question 2

body

Answer 2

soma

Question 3

what do somatosensory receptors connect/synapse to

Answer 3

with pseudounipolar cells

Question 4

Where are somatosensory receptors?

Answer 4

In the skin
Muscles
Joints
And viscera

Question 5

Describe receptor potentials

Answer 5

Local and graded
Amplitude modulated (more volt change for a larger stimulus, etc.)
Carry info about location and nature of stimulus
By the type of receptor, location and where it projects to in the CNS
Intensity coded by amplitude of the receptor potential, the threshold of the receptors and how many (whole hand touching vs one finger)
Duration coded by the duration of the receptor potential
Slowly adapting—continue to respond but at a diminished level throughout the duration of the stimulus
Rapidly adapting- signal the beginning and end of a stimulus
Combinations of receptors cover the full range of information that needs to be encoded

Question 6

what ytpe of fibers conduct action potentials faster

Answer 6

large diameter vs small fibers

Question 7

what is the nomenclature for axons

Answer 7

A, B, C categories (with A being the largest myelinated axons and C being the smallest unmyelinated axons
A group has alpha, beta, gamma and delta subcategories
Other classification system uses roman numerals I, II, III, and IV (the higher the number the slower the conduction velocity so group IV contains the unmyelinated axons

Question 8

is an α-motor neuron or B fibers have higher conduction velosity?

Answer 8

a motor neurons

Question 9

is a roman numeral 1 faster than a roman numeral 3 and is an a fiber faster than a c faster?

Answer 9

yes

Question 10

Is Cutaneous Receptor Distribution equal?

Answer 10

NO,
Areas such as the lips and fingertips are more densely innervated than other areas such as the back
Test by two-point discrimination –the minimum distance by which two stimuli can be separated and still perceived as two stimuli

Question 11

vibration

Answer 11

Pacinian corpuscle

Question 12

touch

Answer 12

Meissner corpuscle
Merkel endings

Question 13

pressure

Answer 13

Ruffini ending

Question 14

Pain, temperature, itch, touch

Answer 14

free nerve endings

Question 15

Detect muscle length

Answer 15

muscle spindles

Question 16

Detect muscle tension
mechanoreceptor

Answer 16

golgi tendon organs

Question 17

the end of a muscle where it becomes a tendon

Answer 17

Aponeurosis

Question 18

Respond to joint position and movement
proprioceptors

Answer 18

joint receptors