NEURO 2 PART 2

Question 1

What is the somatic sensory pathway?

Answer 1

Relay station for information going to the somatosensory region of the cerebral cortex and the cerebellum

Question 2

What are the three types of neurons that pass into the pathways?

Answer 2

First order
Second order
Third order

Question 3

What’s the first order neurons?

Answer 3

Conduct impulses to the receptors of the brain stem or spinal cord

Question 4

What are the cranial nerves of the first order?

Answer 4

Somatic sensory neurons that innervate the face, mouth, teeth, and eyes

Question 5

What are the spinal nerves of the first order?

Answer 5

Send sensory impulses to the neck, trunk, limbs, and posterior head

Question 6

What are secondary order neurons?

Answer 6

Conduct impulses to the brain stem and into the thalamus

*they cross over at the spinal cord before they reach the thalamus. All neruons information reaches the thalamus on the the positive side

Question 7

What are third order neurons

Answer 7

Conduct impulses from the thalamus to the primary somatosensory area

Question 8

What is the relay stations?

Answer 8

An area where neurons synapse with other neurons. The main stations are the thalamus, Brian stem, and spinal cord

Question 9

What is the posterior column medial lemniscus pathway?

Answer 9

Never impulse for touch, pressure, and vibrations and some proprioceptors.

Question 10

What are the pathways of the PCP?

Answer 10

Gracile fascicules (lower body)
Cuneate fascicules (upper body)
*found in the white mater tracts of the spinal cord

Question 11

Describe the pathway of the posterior column

Answer 11

1.First order neurons extend to the sensory receptors of your limbs

2.The cell bodies of these neurons are found in the posterior root ganglion

3.the first order synapses with the second order neurons at the dendrites

4. Once the they enter the medulla it crosses over the the medial lemnisucs

Question 12

What is the medial lemnisucs?

Answer 12

Thin Ribbon like projections that extend from the medulla

Question 13

What is the anterior pathway (spinothalamic)?

Answer 13

Nerve impulses for pain, temperature, itch, and tickle of limbs, trunks, posterior head and neck

Question 14

Do all three neurons compose the anterior lateral pathway?

Answer 14

Yes

Question 15

Describe the pathway of anterior lateral pathways

Answer 15

1.first order neurons synapses with the second order in the posterior horns of the grey matter

2.the second neurons cross over to the opposite spinal cord side to the tracts

3.the second order synapses with the third order at the posterior nucleus of the thalamus

4. They then project into the primary somatosensory area on the same side of the thalamus

Question 16

What is sensory homunculus?

Answer 16

A distorted somatic sensory map of the body

Question 17

What areas have the highest receptors?

Answer 17

Lips
Tongue
Hands
Fingers

Question 18

When you feel something with your right hand, what side of the brain responds to the sensory?

Answer 18

Left side

Question 19

What is the anterior and posterior spinocerebeller ?

Answer 19

Conveys nerve impulse from proprioceptors in the trunk and lower limbs of the same side

*helps with detailed movements and creates smooth movement with good balance

Question 20

Somatic motor pathways

Answer 20

Orhestrate all voluntary and involuntary movements

Question 21

Lower motor neurons provide output for what system

Answer 21

CNS to skeletal muscle fibres
*in the spinal cord and brain stem

Question 22

How does the LMN innervate the cranial regions?

Answer 22

By the lower motor neurons (axon) extending through the cranial nerves to innervate the skeletal muscles of the face and head

Question 23

How does the LMN innervate the spinal nerves?

Answer 23

The axons of the LMN extend through the spinal nerves to innervate the muscles of limbs and trunk

Question 24

What are the four distinct neural circuits?

Answer 24

Local
Upper Motor
Basal nuclei
Cerebellar

Question 25

What are Local circuits

Answer 25

Located close to LMN in the Brian stem and spinal cord Help with specific muscle group coordination

Question 26

What are Upper motor neurons?

Answer 26

Local circuited and provided output ti LMN most UMN synapses with local circuits and some LMN Helps with planning and execution of muscle movement, help regulate of posture and balance, and reflexive movement of head and trunk

Question 27

What do the posterior rami supply?

Answer 27

Synovial joints of vertebral column, deep back mm, overlying skin in a segmental pattern. Facet joints (medial branches), thoracic walk, Dermatomes T2-T12, skin over neck and occipital C2

Question 28

What is sensation?

Answer 28

The subconscious and conscious of external and internal environments Reacts to touch, pressure, vibration, pain, taste.

Question 29

What is Perception

Answer 29

The primary function of the cerebral cortex, awareness of sensory

Question 30

What are the 2 classes of sensory modalities ?

Answer 30

General : contains somatic and visceral Special : taste, smell, vision, hearing, equilibrium

Question 31

What are sensory receptors ?

Answer 31

Are specialized cells or dendrites that respond to one particular kind of stimulus

Question 32

What are the four events for sensation ?

Answer 32

Stimulation Transduction (converts energy in Stimulus into a graded potential) Generation (graded hits threshold and triggers nerve impulse) Integration (traveling to CNS and receiving)

Question 33

What are the four characteristics of receptors?

Answer 33

Location Microscopic Structure Origin Type of stimulus

Question 34

What are the types of microscopic structures?

Answer 34

Free nerve endings -bare dendrites -receptors for pain, temp, tickle, some touch Encapsulated nerve endings -clear structure and respond to some touch pressure and vibrations

Question 35

What are the kinds of graded potential responses

Answer 35

Receptor potential Post synaptic potential

Question 36

What are the three locations

Answer 36

Exteroceptors (external and sensitive) Interceptors (aka visceroceptors and internal ) Proprioceptors ( muscles and tendons, ligaments, inner ear)

Question 37

What are the type of stimulus?

Answer 37

Mechanoreceptors Thermoreceotors Nociceptors Photoreceptors Chemoreceptors osmoreceptors

Question 38

What are the kind of touch

Answer 38

Corpuscles of touch / Meissner (rapid to hairless skin surfaces ) Type 1 cutaneous mechanoreceptors / merkel (fingers, hands, lips, external genitalia and slow) Type 2 cutaneous mechanoreceptors / Ruffini (slow and ligaments and tendons ) Pacinian / lamellated (fast and submucosal membrane )

Question 39

What does the basal nuclei neurons do?

Answer 39

Assist in movement by input to the UMN Helps terminate and imitate movements and normal muscle tone

Question 40

What do cerebellar neurons do?

Answer 40

Assist movement via control of activity of UMN Prime function of cerebellum Monitor differences between intended movements and movements performed Maintain posture and balance

Question 41

What are the two pathways of UMN?

Answer 41

Direct motor pathway (provides input to lower neurons by extending from cerebral cortex) Indirect motor pathways (provides input to lower neurons from basal nuclei, cerebellum, and cerebral cortex)

Question 42

What are the largest representations in the motor homunculus ?

Answer 42

Lips tongue thumbs fingers vocal cords

Question 43

What are pyramidal pathways?

Answer 43

Action potential for voluntary movements propagate from cerebral cortex to LMN