SomatoSensation

Question 1

Proprioception:

Answer 1

The perception of the position
(and movement) of our limbs in space.

Question 2

Kinesthesia:

Answer 2

Specifically refers to perception of
movement of our limbs (often not used)

Question 3

Somatosensation:

Answer 3

A collective term for sensory
signals from the body

Question 4

Touch receptors: Embedded on (2):

Answer 4

(1) outer layer (epidermis)
(2)underlying layer (dermis) of skin

Question 5

there are __ types of touch receptors

Answer 5

multiple

Question 6

Each touch receptor can be categorized by three
criteria:

Answer 6

1. Type of stimulation to which the receptor responds.
2. Size of the receptive field.
3. Rate of adaptation (fast versus slow)

Question 7

Tactile receptors or
“mechanoreceptors” because:

Answer 7

they respond to mechanical
stimulation: Pressure, vibration, or
movement

Question 8

Tactile receptors or
“mechanoreceptors” because
they

Answer 8

respond to mechanical
stimulation: Pressure, vibration, or
movement

Question 9

4 types of mechanoreceptors:

Answer 9

-Meissner corpuscles
‐ Merkel cell complexes
‐ Pacinian corpuscles
‐ SA II

Question 10

each of the 4 receptor has a different:

Answer 10

range of responsiveness

Question 11

Slowly adapting fibers (SA)
found in (2):

Answer 11

Merkel discs (SA I) and SA II receptors

Question 12

• Slowly adapting fibers (SA) fire:

Answer 12

continuously as
long as pressure is applied.

Question 13

Rapidly adapting fibers (RA)
found in (2):

Answer 13

(1) Meissner recepttor
(2) pacinian corpuscule

Question 14

Rapidly adapting fibers (RA) fire at:

Answer 14

onset
and offset of stimulation

Question 15

Receptor Field Size =

Answer 15

Spatial properties - detail resolution

Question 16

SA1 fibers

Answer 16

Merkel receptor

Question 17

SA1 fibers (Merkel receptor) respond to

Answer 17

patterns of grooves

Question 18

RA2 fibers

Answer 18

Pacinian corpuscle

Question 19

RA2 fibers (Pacinian corpuscle) do not respond to

Answer 19

the details of
these stimuli

Question 20

Frequency response:
Ranges from _ for SA1 fibers and __ for RA2 fibers.

Answer 20

0.3 Hz for SA1 fibers
500 Hz for RA2 fibers

Question 21

The firing of Merkel receptors/SA1 fiber signals

Answer 21

the grooved stimulus pattern

Question 22

does the firing of the pacinian corpuscule/RA2 fiber signal the grooved stimulus pattern?

Answer 22

no

Question 23

Merkel receptor/SA1 fiber signals

Answer 23

details

Question 24

Tactile Sensitivity and Acuity - How finely can we resolve
spatial details?

Answer 24

Two
‐point threshold:: The
minimum distance at which
two stimuli are just
perceptible as separate.

Question 25

Two ‐point threshold:

Answer 25

The minimum distance at which two stimuli are just perceptible as separate

Question 26

Like sensitivity to pressure, spatial acuity

Answer 26

varies across the body

Question 27

___show the highest acuity

Answer 27

Extremities (fingertips, face, and toes) show the highest acuity

Question 28

How finely can we resolve temporal details? Touch:

Answer 28

Sensitive to time differences of only 5 ms

Question 29

How finely can we resolve temporal details?Vision:

Answer 29

Sensitive to time differences of 25 ms

Question 30

How finely can we resolve temporal details: Audition:

Answer 30

Sensitive to time differences of <0.01 ms

Question 31

Haptic Perception

Answer 31

Knowledge of the world that is derived from sensory receptors in skin, muscles, tendons, and joints, usually involving active exploration * For instance, aligning the arrows and opening a child ‐proof aspirin bottle in the dark

Question 32

Perception for action:

Answer 32

Using somatosensation to control our impressive ability to grasp and manipulate objects in a stable and highly coordinated manner and to maintain proper posture and balance

Question 33

Action for perception:

Answer 33

Using our hands to actively explore the world of surfaces and objects outside our bodies

Question 34

Exploratory procedure:

Answer 34

A stereotyped hand movement pattern used to contact objects in order to perceive their properties; each exploratory procedure is best for determining one or more object properties ‐ Example: To determine roughness of an object, use lateral motion

Question 35

Haptic Perception: The __ of touch

Answer 35

what system

Question 36

Geometric properties of objects are most important for

Answer 36

visual recognition

Question 37

Material properties of objects are crucial for

Answer 37

haptic recognition

Question 38

“Pop out” stimuli for vision and touch are

Answer 38

different

Question 39

Loomis:

Answer 39

Touch acts like blurred vision when the fingertips explore a raised pattern

Question 40

FAI Fibers and Grip Control

Answer 40

Perceiving slip and maintaining grip control

Question 41

FAII Mechanoreceptors

Answer 41

Perceiving fine textures through transmitted vibration.

Question 42

Tactile agnosia

Answer 42

The inability to identify objects by touch

Question 43

Tactile agnosia caused by

Answer 43

lesions to the parietal lobe

Question 44

Tactile agnosia:Patient documented by Reed and Caselli (1994):

Answer 44

Tactile agnosia with right hand but not left hand * Could not recognize objects such as a key chain in right hand, but could with left hand or visually ‐ Rules out a general loss of knowledge about objects * Other sensory abilities were normal in both hands

Question 45

Frame of reference:

Answer 45

The coordinate system used to define locations in space

Question 46

Egocenter:

Answer 46

The center of a reference frame used to represent locations relative to the body.

Question 47

Body image:

Answer 47

The impression of our body in space

Question 48

Our body image is

Answer 48

highly changeable

Question 49

touch is just one of our “body senses” the others are

Answer 49

- proprioception/kinesthesia ‣ temperature ‣ pain

Question 50

Proprioceptors:

Answer 50

Play an important role in sense of where limbs are, what kinds of movements are made.

Question 51

Golgi tendon Organs:

Answer 51

Receptors in tendons signal tension in muscles attached to tendons.

Question 52

Joint receptors:

Answer 52

react when joint is bent to an extreme angle

Question 53

Strange case of neurological patient Ian Waterman:

Answer 53

Cutaneous nerves connecting Waterman’s kinesthetic mechanoreceptors to brain destroyed by viral infection. Lacks kinesthetic senses, dependent on vision to tell limb positions.

Question 54

Thermoreceptors

Answer 54

Sensory receptors that signal information about changes in skin temperature

Question 55

Two distinct populations of thermoreceptors:

Answer 55

(1) warmth fibers (2) cold fibers

Question 56

Thermoreceptors respond when

Answer 56

you make contact with an object warmer or colder than your skin

Question 57

Nociceptors

Answer 57

Sensory receptors that transmit information about noxious stimulation that causes damage or potential damage to skin.

Question 58

Two groups of nociceptors

Answer 58

A-delta fibers C fibers

Question 59

nociceptors: a -delta fibers:

Answer 59

: Intermediate sized, lightly myelinated sensory nerve fibers that transmit pain and temperature signals

Question 60

nociceptors: c fibers:

Answer 60

Narrow-diameter, unmyelinated sensory nerve fibers that transmit pain and temperature signals.

Question 61

Touch Physiology : Information must pass through

Answer 61

spinal cord

Question 62

Axons of various tactile receptors combine into

Answer 62

single nerve trunks.

Question 63

Touch sensations are represented ___ in the brain

Answer 63

somatotopically

Question 64

S1

Answer 64

Primary somatosensory cortex

Question 65

S2

Answer 65

secondary somatosensory cortex

Question 66

djacent areas on skin connect to

Answer 66

adjacent areas in brain.

Question 67

Homunculus:

Answer 67

representation of regions of the body in the brain.