Week 8 - Sensory Feedback

Question 1

how is voluntary movement created ?

Answer 1

motor neurons bring signals out from the spinal cord to the muscles

Question 2

define perception

Answer 2

the processes of obtaining information about the internal / external environment from sensory stimulation

Question 3

define sensory neurons

Answer 3

(afferent) enter the spinal cord via the dorsal root

Question 4

define interneurons

Answer 4

sit within the CNS

Question 5

define motor neurons

Answer 5

(efferent) exit the spinal cord via the ventral root

Question 6

what are the components of a sensory neuron ?

Answer 6

• cell body
• axon
• peripheral fibre
• central terminal branches
• dendrites

Question 7

define cell body

Answer 7

• contains nucleus and cell machinery

- lie in the dorsal root ganglia

Question 8

define axon

Answer 8

• carries impulses away from cell body into spinal cord

- can continue up spinal cord to brain

Question 9

define peripheral fibre

Answer 9

carries impulses from dendrites to cell body

Question 10

define central terminal branches

Answer 10

make connection with motor neuron dendrites or connector neurons in spinal cord

Question 11

define dendrites

Answer 11

carries impulses from sensory receptors to peripheral fibre

Question 12

define sensory receptors

Answer 12

cells or organs that are selective in their response to different types of stimuli

Question 13

define exteroceptors

Answer 13

• located at / near a body surface

Question 14

define interoceptors

Answer 14

• visceroceptors: impulses from internal organs

- proprioceptors: impulses related to movement

Question 15

define photoreceptors

Answer 15

sensitive to light

Question 16

define mechanoreceptors

Answer 16

sensitive to mechanical inputs

Question 17

define chemoreceptors

Answer 17

sensitive to chemical substances

Question 18

define thermoreceptors

Answer 18

sensitive to thermal energy

Question 19

define sensory adaptation

Answer 19

• the stronger the stimuli, the higher the firing rate in the afferent axon
• response tends to decrease over time if stimulus stays constant

Question 20

what are the 2 types of muscle proprioceptors ?

Answer 20

• muscle spindles

- golgi tendon organ (GTO)

Question 21

define muscle spindles

Answer 21

• lie parallel and between muscle fibres
• sensitive to change in length
• stimulate muscle to produce force to resist stretching