ascending pathways

Question 1

what cranial nerves carries taste

Answer 1

VII and IX (facial and glossopharyngeal)

Question 2

what is interoception

Answer 2

pain, temperature, touch pressure of viscera

Question 3

what is exteroception

Answer 3

pain, temperature, touch pressure of external world

Question 4

what is proprioception

Answer 4

postition sense from joints/tendons/ligaments

Question 5

what do nociceptors detect

Answer 5

monitor tissure damage

Question 6

what do thermoreceptors detect

Answer 6

monitor temperature and hypothalamus

Question 7

what do mechanoreceptors detect

Answer 7

contact and pressure

Question 8

what do chemoreceptors detect

Answer 8

chemical composition of body fluids

Question 9

what do baroreceptors detect

Answer 9

changes in pressure of tubular organs

Question 10

where is the primary motor cortex

Answer 10

precentral sulcus (in frontal lobe)

Question 11

where is the primary sensory cortex

Answer 11

postcentral gyrus (parietal lobe)

Question 12

what is a dermatome

Answer 12

an area of skin supplied by a particular spinal nerve

Question 13

how many dermatomes are in the body

Answer 13

31 dermatomes - 31 spinal segments

Question 14

where is the first neuron between the peripheral receptor and the cerebral cortex.

Answer 14

enters the spinal cord through the dorsal root of a spinal nerve and its cell body lies in the dorsal root ganglion.

Question 15

where does the first order neuron end

Answer 15

terminates in synaptic contact with the 2nd neuron either in the spinal gray matter or in the medulla oblongata

Question 16

what is the function of the first order neuron

Answer 16

makes synaptic connections that mediate spinal reflexes
receive impulses from skin and proprioceptors and send them to the spinal cord

Question 17

where is the second order neuron

Answer 17

has its cell body in the cord or medulla oblongata.

Question 18

describe the path of the second order neuron

Answer 18

Its Axon crosses over to the opposite side of the CNS and ascends to the thalamus where it terminates upon the third neuron.

Question 19

describe the path of the third neuron

Answer 19

has its cell body in the thalamus its Axon passes to the somatosensory cortex in the parietal lobe of the ipsilateral cerebral hemisphere.

Question 20

what are the two paths of the sensory tract of the spinal cord

Answer 20

the dorsal posterior column and the medial lemniscus

Question 21

where does the dorsal column run

Answer 21

from spinal cord to medulla

Question 22

where does the medial lemniscus pathway run

Answer 22

from the medulla to the cortex (continuation of dorsal column)

Question 23

what are the two tracts of the dorsal columns

Answer 23

the fasciculus gracilis situated medially and the fasciculus cuneatus situated laterally

Question 24

where is the dorsal column located

Answer 24

between the dorsal median sulcus and the dorsal horn.

Question 25

what do the tracts of the dorsal column carry

Answer 25

carry impulses concerned with proprioception and discriminative touch. The dorsal columns contain primary afferent neurons they carry information relating to the ipsilateral side of the body

Question 26

where does the fasciculus gracilis enter the spinal cord

Answer 26

that join the cord at sacral lumbar and lower thoracic levels and thus includes those from the lower limb.

Question 27

where does the the fasciculus cuneatus enter the spinal cord

Answer 27

via the upper thoracic and cervical dorsal roots and thus involve those from the upper limb.

Question 28

what information does the spinothalamic tract carry

Answer 28

to pain and thermal sensations and also non discriminative touch and pressure.

Question 29

Interoception, exteroception and proprioception from trunk and limbs are delivered to the CNS by ________

Answer 29

first order neurons (PNS) to the spinal cord.

Question 30

describe the path of Pain, temperature and crude touch pathways

Answer 30

decussate in the spinal cord and ascend contralaterally via the STT to the primary somatosensory cortex.

Question 31

describe the path of Tactile and proprioceptive pathways

Answer 31

ascend ipsilaterally via the fasciculus gracilis and the fasciculus cuneatus before decussating in the brainstem to ascend contralaterally to the primary somatosensory cortex.

Question 32

what does the Trigeminothalamic tract provides somatic sensation to

Answer 32

face and head

Question 33

where is the trigeminal ganglion

Answer 33

convergence of the ophthalmic, maxillary and mandibular nerves.

Question 34

where does the chief sensory nucleus lie

Answer 34

the pontine tegmentum close to the entry of the trigeminal nerve.

Question 35

what is the function of the chief sensory nucleus

Answer 35

. It mediates fine touch stimuli, joint position and vibration.

Question 36

what is the function of the spinal nucleus

Answer 36

It mediates pain and temperature.

Question 37

where does the trigeminal sensory nucleus run

Answer 37

extends throughout the length of the brain stem and into the upper cervical spinal cord.

Question 38

what is the spinal nucleus

Answer 38

the nucleus of the spinal tract of the trigeminal

Question 39

Proprioceptive afferents from the muscles of mastication and the temporomandibular joint have their cell bodies in the ______

Answer 39

mesencephalic nucleus of the trigeminal

Question 40

what are the only primary afferents to have their cell bodies located within the CNS

Answer 40

afferents from the muscles of mastication and the temporomandibular joint

Question 41

Axons of 2nd order neurons in the trigeminal nucleus decussate to form the _______

Answer 41

contralateral trigeminothalamic tract to the ventroposteromedial (VPM) nucleus of the thalamus.

Question 42

3rd order neurons in the thalamus project to the _______

Answer 42

postcentral gyrus i.e. primary sensory cortex.

Question 43

what is syringomyelia

Answer 43

disrupts the decussating fibres of the spinothalamic system