Somatosensory System (Mixed)

Question 1

Broadmann’s Area: Sensory Association Area

Answer 1

39 and 40

Question 2

Pathway: Critical for adjusting movesments and posture

Answer 2

Spinocerebellar

Question 3

Cortical Area: Classification of sounds

Answer 3

Secondary Auditory (B 42)

Question 4

Describe how small efferent fibers adjust spindle fiber length

Answer 4

Small efferents/gamma motor neurons adjust spindle fiber length via specialized intrafusal spindles. There spindles are then responsive through the physiologic range of muscle length

Question 5

Describe the function of the divergent pathway

Answer 5

It’s the medial pain system that carries slow aching diffuse pain

Question 6

Cortical Area: Stereognosis and memory of the tactile and spatial environment

Answer 6

Secondary Somatosensory (B 5&7)

Question 7

Receptor: Alpha Delta

Answer 7

Free nerve ending: conscious pain, temperature, coarse touch

Question 8

Divergent Pathway: Synapses in medial and intralaminar nuclei of thalamus and projects to limbic system

Answer 8

Spinolimbic

Question 9

Divergent Pathway: Synpases in superior colliculus and periaqueductal gray

Answer 9

Spinomesencephalic

Question 10

Divergent Pathway: Synapses in brainstem reticular formation, functions for arousal, attention, sleep/wake cycles

Answer 10

Spinoreticular

Question 11

Receptor: Alpha Beta - Pressure

Answer 11

Merkel’s disc and hair follicles

Question 12

Cortical Area: Distinguishes intensity of light, shape, size, and location of objects

Answer 12

Primary visual (B 17)

Question 13

Cortical Area: Discriminates shape, texture, or size of objects

Answer 13

Primary Somatosensory (B 312)

Question 14

Receptor: Ia

Answer 14

Proprioception, muscle spindles, phasic

Question 15

Term: Integration of tactile and proprioceptive information from manipulating an object

Answer 15

Sterognosis

Question 16

Receptor: Alpha Beta - Touch and vibration

Answer 16

Meissner’s (s) and Pacinian (d)

Question 17

Receptor: C

Answer 17

Free nerve ending, unconscious pain, tempterature, itch, tickle

Question 18

Receptor: Alpha Beta - Skin stretch

Answer 18

Ruffini’s Endings (d)

Question 19

Receptor: Type of LMN

Answer 19

Ia afferents and Gamma efferents

Question 20

Term: area of skin innervated by a single afferent neuron

Answer 20

Receptive field

Question 21

Cortex: Patterns of activity and anticipation

Answer 21

Secondary (somato)sensory cortex

Question 22

Cortical Area: Conscious discrimination of loudness and pitch of sound

Answer 22

Primary Auditory (B 41)

Question 23

Receptor: Ib

Answer 23

Proprioceptive, GTO, phasic/tonic

Question 24

Receptor: II

Answer 24

Propriocetive, muscle spindles, tonic

Question 25

Cortical Area: Analysis of motion, color, and control of visual fixation

Answer 25

Secondary visual (B 18&19)

Question 26

Receptors: Primary superficial fine toch

Answer 26

Meissner’s corpuscles and Merkel’s discs

Question 27

Structure: Sensory organ embedded in skeletal/extrafusal muscles

Answer 27

Muscle Spindle

Question 28

Stimuli Muscle Spindles Respond to

Answer 28

Muscle stretch

1. Quick and tonic stretch registered by Ia
2. Tonic stretch registered by II

Question 29

Pathway: Unconscious proprioception

Answer 29

Spinocerebellar