Somatic sensation

Question 1

Mechanisms that collect sensory information from all over the body

Answer 1

Somatic senses

Question 2

Stimulated by mechanical displacement of some tissue. Tactile and position sensations

Answer 2

Mechanoreceptive Somatic senses

Question 3

Detect heat and cold

Answer 3

Thermoreceptive senses

Question 4

Activated by factors that damages the tissues

Answer 4

Pain sense

Question 5

From the surface of the body

Answer 5

Exteroreceptive sensations

Question 6

Relates to the physical state of the body (position, pressure, equilibrium)

Answer 6

Proprioreceptive sensations

Question 7

Deep pressure, pain and vibration from deep tissues like fasciae, muscles, bone

Answer 7

Visceral sensation

Question 8

Rapidly repetitive sensory signals

Answer 8

Tactile

Question 9

Detect pressure and touch. Found in cornea

Answer 9

Free nerve endings

Question 10

Elongated encapsulated nerve ending of a large (type AB) myelinated sensory nerve fiber

Answer 10

Meissner’s corpuscle

Question 11

Transmit initially strong but partially adaptive signal. Type of an expanded tip tactile receptors

Answer 11

Merkerl’s discs

Question 12

Detects any slight movement of any hair in the body

Answer 12

Hair end-organ

Question 13

Adapts slow and multibranched encapsulated endings

Answer 13

Ruffini’s ending

Question 14

Stimulated only by rapid local compression of the tissues. Adapts in a few hundredths of a second and partially important for detecting vibration

Answer 14

Pacinian corpuscle

Question 15

Detects high frequency vibrations

Answer 15

Pacinian corpuscle

Question 16

Smaller and very small nerve fibers

Answer 16

Cruder types

Question 17

Detected by free nerve endings found in the superficial layers if the skin. Small type C unmyelinated fibers

Answer 17

Tickling/ Itch

Question 18

Decussate at the level of the lower medulla oblongata after synapsing in the dorsal column nuclei

Answer 18

Second order neurons

Question 19

Project the ventrobasal complex of the thalamus tonthe somatic sensory are 1 and 2 in the postcentral gyrus

Answer 19

Third order neurons

Question 20

Where sensation we feel are processed

Answer 20

Somatosensory area

Question 21

Primary somatosensory area 1

Answer 21

Areas 1,2, and 3

Question 22

Somatosensory association area

Answer 22

Area 5 and 7

Question 23

Brain division using numbers based on the kind of histology for each area

Answer 23

Brodmann area

Question 24

Somatosensor cortex always means

Answer 24

Area 1

Question 25

What are the layers of the somatosensory cortex

Answer 25

Molecular layer External granular layer Small pyramidal cell Internal granular layer Large pyramidal cell Fusiform

Question 26

Where is Brodmann area 5 and 7 located

Answer 26

behind somatosensory 1

Question 27

Loses the ability to recognize complex objects and complex forms felt on the opposite side of the body

Answer 27

Amorphosynthesis

Question 28

What happens when somatosensory are is exercised?

Answer 28

Unable to discrete different sensation Unable to judge pressure Unable to judge weights Unable to judge shapes Unable to judge texture

Question 29

aka “surrounds inhibition” Inhibitory signals spreading to the sides of the excitatory signal and inhibit adjacent neurons

Answer 29

Lateral inhibition

Question 30

Unable to judge shape or form is called

Answer 30

Astereognosis

Question 31

Loses ability to recognize complex objects and complex forms felt on the opposite side of the body

Answer 31

Amorphosynthesis

Question 32

What areas are part of somatosensory association areas

Answer 32

Brodmann Area 5 and 7

Question 33

The greater the background sensory intensity, the greater an additional change must be for the psyche to detect the change

Answer 33

Webr-Fechner principle

Question 34

Also called “Proprioceptive senses”

Answer 34

Position senses

Question 35

Linear relationship exists between interpreted stimulus strength and actual stimulus strength

Answer 35

Power law

Question 36

Conscious perception of the orientation of the different parts of the body with respect to one another

Answer 36

Static position sense

Question 37

Also called kinesthesia or dynamic proprioception

Answer 37

Rate of movement sense

Question 38

It detects rate of movement

Answer 38

Pacinian corpuscle

Question 39

Decussate immediately in the anterior commissure of the cord to the opposite anterior and lateral white columns

Answer 39

Second order neurons

Question 40

Project from the ventrobasal complex and intralaminar nuclei of the thalamus to the somatic sensory area 1 and 2 in the postcentral gyrus

Answer 40

Third order neurons

Question 41

Role of thalamus in somatic sensation

Answer 41

relay sensory information to the cortex

Question 42

Signals that are transmitted in the backward direction

Answer 42

Corticofugal signals

Question 43

Each spinal nerve innervates a segmental field of the skin called

Answer 43

Dermatomes

Question 44

Dermatome T4

Answer 44

Nipple line

Question 45

Dermatome T10

Answer 45

Umbilical region

Question 46

Dermatome C7

Answer 46

Middle finger

Question 47

Dermatome S5

Answer 47

Anal part

Question 48

Higher frequency vibratory signals originate from pacinian corpuscle

Answer 48

Vibratory sensation