Ch 13: Touch

Question 1

Describe the types of somatosensation.

Answer 1

kinesthesis– coodinate how you’re moving about the environ (limbs); proprioception– how the entire body is moving (kinesthetic and vestibular); somatosensation; all sensory signals from the body (touch, pain, cool sensation…)

Question 2

Describe the four types of mechanoreceptors for touch.

Answer 2

Meissner- small receptive fields in the epidermis & fast adaptation rate, 5 to 50 Hz; Pacinian- large receptive fields in the dermis & fast adaptation rate, higher frequency; Merkel- slow adap rate & small receptive field in epidermis, very low frequency; Ruffini– in dermis, slow adap rate & large recep field indermis

Question 3

Describe the kinesthetic receptors and consequences of damage to these receptors.

Answer 3

spindles- convey the rate at which the muscle fibers are changing in length; tendons’ receptors provide signals about tension in muscles attached to tendons; joint receptors react when joint is bent to extreme angle; consequence– damage to musculoskeletal system

Question 4

Describe the homunculus and somatotopic mapping.

Answer 4

sensory map; adjacent areas on skin are connected to adj areas in brain; there are overrepresentations (fingers, lips) due to high acuity

Question 5

Describe phantom limbs and their relationship to somatotopic mapping

Answer 5

after amputation, can feel sensation from the limb that is no longer there; brain is not fully aware that the limb is missing (product of neuroplasticity)

Question 6

Describe haptic perception and the exploratory procedures used in haptic perception.

Answer 6

object identification through sense of touch; lateral motion, pressure, static contact, unsupported holding, enclosure, contour following

Question 7

Describe tactile agnosia.

Answer 7

inability to recognize objects by touch; damage to anterior portion of parietal lobe; not able to integrate features