Brain stem and diencephalon

Question 1

what are the 3 primary vesicles?

Answer 1

Prosencephalon; mesencephalon; rhombencephalon;

Question 2

what are the 5 secondary vesicles? What structures do they give rise to?

Answer 2

Telencephalon (cerebrum); Diencephalon; mesencephalon; Metencephalon (Cerebellum and Pons); Myelencephalon (Medulla oblongata)

Question 3

what structures does the Prosencephalon become>

Answer 3

Telencephalon; diencephalon;

Question 4

what structures does the Mesencephalon become?

Answer 4

Mesencephalon;

Question 5

what structures does the Rhombencephalon become?

Answer 5

Metencephalon; Myelencephalon

Question 6

In the orientation of the brain what is anterior referred to? Posterior? Superior? Inferior?

Answer 6

Rostral; caudal; Dorsal; Ventral

Question 7

the meynert axis is through what structures? Forel axis is through what structures?

Answer 7

Spinal cord; Cerebrum and diencephalon

Question 8

the brainstem is located between? It is composed of what three structures?

Answer 8

Located between the diencephalon (interbrain) and spinal cord; Midbrain; Pons; Medulla oblongata

Question 9

what ventricle is associated with the pons medulla and cerebellum?

Answer 9

4th ventricle

Question 10

what are the ventricles in the cerebrum?

Answer 10

1st and 2nd (lateral) ventricles

Question 11

what is the ventricle of the interbrain? What is the interbrain?

Answer 11

3rd ventricle

Question 12

what is the ventricle of the midbrain?

Answer 12

aqueduct

Question 13

what is the ventricle of the spinal cord?

Answer 13

central canal

Question 14

the CSF flows form the ventricle to the subarachnoid space via three foramina located in what ventricle? What are the foramina called?

Answer 14

4th ventricle; There is one median called the Magendie; and two lateral called the Luschka foramina

Question 15

what is the defining feature of the mesencephalon (posteriorly)?

Answer 15

superior and inferior colliculus

Question 16

almost all cranial nerves arise from the? What nerves do not arise from this?

Answer 16

Brain Stem; Olfactory and Optic nerves

Question 17

what are the three longitudinal substructures of the brainstem? From anterior to posterior

Answer 17

Base; Tegmentum; tectum

Question 18

the base of the brainstem contains only?

Answer 18

Descending fibbers

Question 19

what does the superior and inferior Colliculus are important in?

Answer 19

Superior colliculus: is important for reflex movement of the head towards stimulus (e.g. Light; noise etc.); Inferior colliculus: is a relay station for the auditory pathway

Question 20

the tegmentum contains? (three things)

Answer 20

ALL Ascending pathways; ALL Nuclei of the cranial nerves; some descending pathways; prominent nuclei (reticular formation; red nucleus; substantia nigra)

Question 21

the Base is composed of?

Answer 21

crus cerebri of the mid-brain; base of the pons; pyramids of the medulla

Question 22

Crus cerebri contains?

Answer 22

Crus cerebri contains all descending pathways that originate from brain hemispheres (e.g. pyramidal tract

Question 23

the major dopamine containing neurons in the brain are located in ?

Answer 23

the substantia nigra and VTA

Question 24

the destruction of the substantia nigra is associated with disease?

Answer 24

Parkinson’s disease

Question 25

the pons is wedged between what two structures? It release information to and from what?

Answer 25

midbrain and medulla; cerebellum and cerebrum/spinal cord

Question 26

the pons maintains contact with the cerebellum through the?

Answer 26

Middle cerebellar peduncle

Question 27

most nuclei of the cranial nerves are located in?

Answer 27

the pons

Question 28

what cranial nerve emerges from the pons? What cranial nerves emerge at the border between the pons and medulla

Answer 28

Cranial nerve V (trigeminal); cranial nerves VI-VIII emerge at the border between the pons and medulla

Question 29

the medulla contains what major structures? What does this structures contain?

Answer 29

Pyramid; contains the pyramidal tract

Question 30

the reticular formation is located in the? It is made up of what four zones?

Answer 30

Tegmentum of midbrain pons and medulla; Midline zone (consists of the raphe nuclei); Medial Zone (Controls Motor activity); Lateral Zone(processes sensory information); intermediate field (Locus Coeruleus)

Question 31

the major purpose of the reticular formation is to?

Answer 31

Regulate activity throughout the nervous system

Question 32

Damage to the reticular formation or axons of the reticular activating system can result in?

Answer 32

States of altered consciousness: (Coma; Stupor; Vegetative State)

Question 33

the locus coeruleus is located? Its axons project to? It modulates? And it is linked to?

Answer 33

Pons; axons project to all parts of the CNS; modulates pain; attention; and mood; is linked to depression; anxiety; and post-traumatic stress disorder

Question 34

the Rapha nuclei are located? It is the largest collection of what type of neurons in the CNS? It modulates?

Answer 34

are located in the median part of the whole brainstem and are the largest collection of serotonergic neurons in the CNS; modulates pain; attention; and mood

Question 35

what are the four tracts for unconscious movements? They make up?

Answer 35

Tectospinal tract; Rubrospinal tract; Reticulospinal tract; Vestibulospinal tract; The Extrapyramidal system

Question 36

what are the two tracts for conscious movements? They make up?

Answer 36

corticospinal tract; cortico[bulbar]nuclear tract; Pyramidal system

Question 37

the pyramidal system originates in? the Extrapyramidal System originates in?

Answer 37

Pyramidal system originates in the Cerebral cortex; the Extrapyramidal system originates in the Brain stem

Question 38

At levels of brachial & lumbosacral plexuses; the à & gamma-motoneurons that supply the axial muscles are located in? whereas those that supply the limb muscles are located on the?

Answer 38

At levels of brachial & lumbosacral plexuses; the à& ?-motoneurons that supply the axial muscles are located in the medial part of the anterior horn referred to as the medial motoneurons pool; whereas those that supply the limb muscles are located on the lateral giving rise to the lateral motoneurons pool

Question 39

All motor pathways are located either the?

Answer 39

lateral or ventral funiculi of the spinal cord

Question 40

the lateral motor pathways feed into the? What two tracts make up this? They control what?

Answer 40

Feed into the lateral motoneurons pool; contains the lateral corticospinal tract and the rubrospinal tract; they control the fine voluntary movement of limb muscles and flexor-biased movement of upper limbs

Question 41

the medial motor pathways feed into the? What four tracts make up this? They control what?

Answer 41

feed into the medial motoneuron pool; contains the anterior corticospinal tract; reticulospinal tract; vestibulospinal tract; tectospinal tract; controls postural & reflex movement of axial muscles

Question 42

describe the general characteristics of the medial descending motor system?

Answer 42

mostly extrapyramidal tracts; is phylogenetically older than the lateral descending motor system; controls coordinated whole-body postural and orienting movements

Question 43

describe the general characteristics of the lateral descending motor system?

Answer 43

is phylogenetically younger than all other descending motor tracts and highly developed in humans; is concerned with movements of the limbs (with more emphasis on distal limbs for fine movement)

Question 44

where are the cell bodies of the upper motor neurons located? (two systems; two locations)

Answer 44

pyramidal tract (located in motor cortex of the brain); extrapyramidal tract(located in motor nuclei of the brainstem)

Question 45

Spinal reflex's involve? They are? And they do not require?

Answer 45

SPINAL REFLEXES: involve the spinal cord; are automated & stereotyped (predictable)reflexes; Do NOT require cortical input

Question 46

supraspinal reflexes involve? They are? And they require?

Answer 46

SUPRASPINAL (POSTURAL) REFLEXES; involve spinal cord & supraspinal centres; are NOT stereotyped reflexes; instead they are flexible and goal-oriented (adaptive) reflexes; mostly coordinate their action with voluntary movements (goal oriented); hence require cortical input for coordination of their actions

Question 47

the task of supraspinal reflexes is to?

Answer 47

to maintain equilibrium during ongoing voluntary movements (goal-oriented anticipatory reflex that is flexible and can improve after training; hence adaptive reflex); to regain equilibrium when it is disturbed (automated fast reflex that is less flexible)

Question 48

where does the rubrospinal tract originate? Where does it decussate?

Answer 48

Rubrospinal tract originates in the red nucleus and decussates near its origin at midbrain level

Question 49

The rubrospinal tract descends with what other tract? Where do they descend

Answer 49

The tract descends contralaterally and accompanies the lateral corticospinal tract (lateral motor pathway)

Question 50

the rubrospinal tract innervates?

Answer 50

The tract innervates all flexor muscles of the upper limbs ("grabbing? behaviour)

Question 51

the rubrospinal tract receives inputs from?

Answer 51

The rubrospinal tract gets input from the pyramidal system; Cell bodies of the rubrospinal tract are located in the red nucleus and receive inputs from motor cortex

Question 52

what are the primary functions of the Reticulospinal tract?

Answer 52

It serves postural (upright position) & gait adjustments (balance) during movement (by acting on anti-gravity muscles; e.g. extensor muscles of the leg; hip; arm; and back (extensor-biased tract)); maintain body posture.

Question 53

what are the two divisions of the Vestibulospinal tract? What are there functions?

Answer 53

Lateral vestibulospinal tract generates muscle tone (tonic active) in deep back & limb extensors in response to gravity (to maintain stance & balance); Medial vestibulospinal tract subserves selective and coordinated head and neck movements in response to sensory input from the vestibular system (mainly semicircular canals)

Question 54

The tectospinal tract controls reflex movements of the?

Answer 54

The tectospinal tract controls reflex movements of the head; neck & upper limbs in response to all relevant sensory stimuli(visual; auditory; tactile; temperature; pain etc.)

Question 55

describe the blood supply of the brain stem

Answer 55

Paravertebral arteries become the basilar artery; splits at the top of the brainstem to become the two posterior cerebral arteries

Question 56

the diencephalon consists of ?

Answer 56

the diencephalon consists of the Thalamus; Hypothalamus; Epithalamus; Subthalamus; metathalamus and the 3rd ventricle

Question 57

the thalamus is an important relay station for?

Answer 57

Thalamus is an important relay station for general sensation; special senses (except olfactory); and motor signals to the cerebral cortex. Partially; it also relays pathways of the limbic system

Question 58

the hypothalamus plays a vital role in what?

Answer 58

Hypothalamus plays a vital role that includes various domains; e.g. it links nervous and endocrine system (the ?master gland?); modulates the autonomic nervous system; controls blood pressure; body temperature; hunger; thirst; and circadian rhythm. Briefly it maintains the homeostasis.

Question 59

the Subthalamus is functionally part of? It plays a role in modulating?

Answer 59

Subthalamus functionally part of the basal ganglia and plays a role in modulating motor activity

Question 60

What are the three parts of the Epithalamus?

Answer 60

Pineal body (involved in control of the circadian rhythm) ; Habitual (variety of functions); Stria medullaris ( contains fibre bundles to the habitual)