Lecture 3

Question 1

Question 2

Question 3

Spinal cord

Answer 3

White matter organized into tracts (bundles of nerve fibers with similar function)
Each tract has a defined beginning and end point
Each tract transmits a specific type of information
Ascending (cord to brain) tracts vs descending tracts (brain to effector neurons)

Question 4

white and grey matter
butterfly shape grey matter
Discrimination of afferent signals in different tracts
E.g.Vibration, Temperature, Pain, Pressure

Question 5

Tract named according to

Answer 5

origin and termination
Eg: ventral spinocerebellar tract: ascending, from stretch receptors to spinal chord to cerebellum)
Eg: ventral corticospinal tract, descending, from motorcortex to spinal chord motorneurons, to muscles
Damage to particular areas can interfere with some function, leaving others intact

Question 6

Defined ascending and descending tracts

Question 7

Question 8

Question 9

Ascending tracts

Question 10

Descending tracts

Question 11

In the spinal chord, grey matter is

Answer 11

functionally organized

Question 12

Dorsal horn

Answer 12

(interneurons)

Question 13

ventral horn

Answer 13

(efferent motorneurons)

Question 14

lateral horn

Answer 14

(cell bodies for autonomic control of cardiac and smooth muscle and glands

Question 15

Question 16

Spinal nerves:

Answer 16

31 pairs+12 pairs cranial nerves
carry both afferent and efferent fibers, connect via dorsal and ventral root
Cell bodies for afferent fibers: spinal ganglion
Nerve: bundle of peripheral neuronal axons (no neurons)

Question 17

Question 18

Question 19

Question 20

Question 21

Spinal cord and dermatome

Answer 21

Each segment of the spinal cord supplies a defined region afferent and efferent –> sensory and motor deficits can be asessed

Question 22

Sensory region per spinal nerve:

Answer 22

dermatome

Question 23

Each spinal nerve also contains nerve fibers for internal organs –> referred pain (Head’s zones)

Question 24

Can have segmental injuries and viral infections

Question 25

Spinal nerve lesion or peripheral nerve lesion?

Answer 25

Dermatomes vs nerve specific field of sensory innervation