Neuroscience Week 3: Lab 2 Study Guide

Question 1

Identify

Answer 1

Question 2

Houses the caudate head in its lateral wall

Answer 2

Frontal horn of the lateral ventricles

Question 3

extends deep into the occipital lobe

Answer 3

Occipital horn

Question 4

houses the hippocampus in its anterior medial wall

Answer 4

Temporal horn of lateral ventricles

Question 5

(aka trigone) is the convergence of the body, and temporal and occipital horns

Answer 5

Atrium

Question 6

Choroid plexus is found in?

Answer 6

s the temporal horn, body and atrium produces cerebrospinal fluid (CSF)  CSF flows from the lateral ventricles through the paired foramina of Monro into the 3 rd Ventricle

Question 7

within the midbrain connects the 3rd and 4th ventricles.

Answer 7

Narrow cerebral aqueduct (of Sylvius)

Question 8

CSF from the 4 th ventricle flows into the subarachnoid space through the

Answer 8

foramen of Magendie (in midline) and the bilateral foramina of Luschka (laterally)

Question 9

Dural venous channels are mostly filled with ________ because the rate of ________ and ____________ is far slower than the rate of ___________ and ____________ into and out of the cranial vault

Answer 9

Dural venous channels are mostly filled with blood because the rate of CSF production and reabsorption is far slower than the rate of blood entry and reabsorption into and out of the cranial vault

(about 20ml per hour).

Question 10

Arachnoid granulations comprise

Answer 10

e arachnoid villi, which drain from the subarachnoid space into the venous sinuses.

Question 11

Neoplastic arachnoid villi cells form

Answer 11

meningiomas; thus meningiomas are typically found where there are the greatest concentration of arachnoid villi: at the cerebral convexity (falx cerebri) and base of the skull

Question 12

Basal ganglia Description

Answer 12

The basal ganglia are deep brain nuclei that are involved in motor function and addiction/reward behaviors.

Question 13

Parts of the Basal ganglia

Answer 13

Caudate nucleus

Putamen

Globus pallidus

Question 14

Identify

Answer 14

Question 15

Caudate nucleus

Answer 15

has a c-shaped structure with a rostral/superior Head, a Body extending caudally Tail projecting inferiorly into the temporal lobe

Question 16

Putamen

Answer 16

Collectively, the caudate and Putatmen are known as The Striatum due to the striations that connect them.

Question 17

Globus pallidus

Answer 17

which incorporates an External (lateral) and Internal (medial) segment, sometimes referred to as Palladium

Question 18

Collectively the Putamen and the Globus Pallidus are known as

Answer 18

Lentiform nucleus due to their lens shape.

Question 19

Lentiform nucleus is composed of?

Answer 19

Collectively the Putamen and the Globus Pallidus

Question 20

Thalamus

Answer 20

The thalamus is a deep brain structure that relays information between cortex and brainstem and between cortical structures.

Question 21

Thalamic nuclei

Answer 21

the thalamus consists of a large number of nuclei that form eight nuclear masses according to their anatomic locations. It can be divided into three major subdivisions: Anterior, Medial and Lateral.

Question 22

Identify

Answer 22

Question 23

Identify

Answer 23

Question 24

Corticospinal Motor Pathway

Answer 24

• Originates from upper motor neurons located within the Primary Motor Cortex of the precentral gyrus.
• Descends through the white matter of the cerebral hemisphere (corona radiate) and then the Posterior Limb of the Internal Capsule.
• Exits the cerebrum via the crus cerebri (Cerebral Peduncles) of the Midbrain.
• Continues descending internally through the base (ventral surface) of the Pons.
• Forms the prominent Pyramids of the Medulla.
• At the junction of the Medulla and Cervical Spinal cord, the fibers decussate (crossover) and enter the column of white matter in the spinal cord on the side opposite of where they originated.
• Synapse on Lower Motor Neurons (Second Order Neurons) in the anterior horn which exit at the appropriate level.

Question 25

Dorsal Column Medial Lemniscal Pathway

Answer 25

Question 26

Anterolateral Pathway / Lateral Spinothalamic tract

Answer 26

Question 27

Identify

Answer 27

Question 28

Decerebrate posturing

Answer 28

• occurs when brainstem impairment occurs between the levels of the rostral poles of the red nucleus and vestibular nuclei.
• Both upper and lower limbs extend when a comatose patient receives an appropriate stimuli (startling painful or auditory).
• Extensor posturing is likely because of impaired extensor inhibition.

Question 29

Decorticate posturing

Answer 29

• occurs when the brainstem lesion occurs more rostrally above the red nucleus (shown in dark blue).
• The lower limbs extend and the upper limbs flex following appropriate stimulus in a comatose patient.

Question 30

Control of Facial Motor Function

Answer 30

• Corticobulbar input is bilateral to the portion of the facial nucleus innervating the frontalis and orbicularis oculi muscles (upper face).
• The fibers innervating the muscles of facial expression in the lower half of the face arise in the portion of the nucleus that receives only contralateral corticobulbar projections.

Question 31

UPPER MOTOR VS LOWER MOTOR NEURON FACIAL WEAKNESS

Answer 31

• With an upper motor lesion (Lesion A), the upper face is spared because both hemispheres can compensate.
• With a lower motor neuron lesion (Lesion B), the entire face is affected on one side.

Question 32

Control of Ocular Motor Function

Answer 32

• Brainstem motor nuclei that innervate extraocular muscles (CNIII, IV and VI) do not receive direct corticobulbar innervation.
• Coordinated eye movements are carried out by cortical input to centers in the reticular formation either in the midbrain or pons, that project to the various brainstem nuclei on both sides of the midline (R and L, CNIII, IV or VI).
• Voluntary horizontal movement of the eyes is controlled by neurons in the frontal eye fields of the cerebral cortex, and each hemisphere evokes conjugate eye movement towards the opposite side.

Question 33

Upper motor neuron type facial weakness vs Lower motor neuron type

Answer 33

Question 34

Identify

Answer 34

Question 35

Identify & Cord Segment

Answer 35

Question 36

Identify & Cord Segment

Answer 36

Question 37

Identify & Cord Segment

Answer 37

Question 38

Identify & Cord Segment

Answer 38

Question 39

Identify & Cord Segment

Answer 39