Introductory to Sensory Sytems

Question 1

Exteroception

Answer 1

Perception of stimuli from outside the body

Question 2

Interoception

Answer 2

Perception of stimuli from within the body

Question 3

Proprioception

Answer 3

Joint & muscle position sense

Question 4

A-alpha or group I nerve fibers

Answer 4

Muscle tension

Question 5

A-beta or group II nerve fibers

Answer 5

Touch, pressure & proprioception

Question 6

A-gamma

Answer 6

Motor

Question 7

A-delta or group III

Answer 7

Excessive mechanoreceptors & nociceptors

Question 8

B nerve fibers

Answer 8

Pre-ganglionic sympathetics

Question 9

C nerve fibers or group IV

Answer 9

Nociceptors, thermo-receptors & ANS post-ganglionics

Question 10

Which nerve fibers are unmyelinated?

Answer 10

C or group IV nerve fibers

Question 11

Sensory transduction

Answer 11

Converting sensory information into an AP

Question 12

What is unique about receptor potentials

Answer 12

Graded

Larger membrane depolarization if a larger stimulus is used (not all or none)

Question 13

Name 2 types of sensory transducers

Answer 13

1. Nerve ending itself

2. Another cell (hair cell for hearing or rods for vision) will release a NT

Question 14

Modality

Answer 14

Physical phenomenon sensed through set pathways “labeled lines”, anything that activates that pathway will be interpreted as that phenomenon i.e. pressure on eyeballs is perceived as light

Question 15

Intensity of a stimulus is conveyed by

Answer 15

Frequency of APs

Question 16

Type 1: Rapidly Adapting fibers

Answer 16

Respond to change
Desensitize\adapt very quickly
So only notice when a stimulus is applied or removed

Question 17

Type 2: Slow Adapting Fibers

Answer 17

Continue firing until a stimulus is removed

Question 18

Receptive field is measured by

Answer 18

2 point discrimination tests

Question 19

What increases the speed of a neuron

Answer 19

Increased diameter

Myelination

Question 20

Dorsal column-medial lemniscal pahway

Answer 20

Fine touch, vibration, proprioception & localized pressure

Question 21

Meissner’s corpuscle

Answer 21

Well localized touch

Question 22

Ruffi endings

Answer 22

Touch

Question 23

Pacinian corpuscle

Answer 23

Vibration

Question 24

Muscle spindles

Answer 24

Stretch

Question 25

Joint receptors

Answer 25

Joint position

Question 26

Golgi tendon

Answer 26

Muscle tension

Question 27

Anterolateral system

Answer 27

Pain, temperature & crude touch

Question 28

Anterolateral system decussates in the

Answer 28

Spinal cord, fibers called spinothalamic tract

Question 29

Dorsal Column Medial Lemniscus Pathway decussate in the

Answer 29

Medulla, fibers form the medial lemniscus

Question 30

Unilateral damage to cervical spinal cord or lateral medulla

Answer 30

Pain, T and crude touch lost from ipsilateral face (Trigeminothalamic pathway)

Question 31

Give nucleus where the 1st order neurons synapse with second order neuron

1. Trigeminothalamic Pathway (localized touch, pressure, vibration & proprioception)
2. Trigeminothalamic Pathway (crude touch, tempreture & pain)
3. Trigeminocerebellar Pathway (Proprioceptive Information)

Answer 31

1. Primary sensory nucleus
2. Spinal Trigeminal Nucleus
3. Mesencephalic nucleus

Question 32

Spinoreticular Tract

Answer 32

Pain, temperature, & light touch

Reflexes

Question 33

Spinotectal Tract

Answer 33

Orienting response

Question 34

Periaqueductal Gray

Answer 34

Descending pathways that regulate pain

Question 35

Name 3 Proprioceptive Pathways

Answer 35

1. Dorsal spinocerebellar pathway
2. Ventral spinocerebellar pathway
3. Cuneocerebellar Pathway

Question 36

Which proprioceptive pathway crosses twice

Answer 36

Ventral spinocerebellar pathway

Question 37

WHich pathway includes synapses on Clarke’s column & External nucleus

Answer 37

Dorsal spinocerebellar pathway

Question 38

Which pathway includes only a synapse on Clarke’s column

Answer 38

Cuneocerebellar Pathway