Week 4

Question 1

What is the largest of the 3 peduncles ?

Answer 1

The middle cerebeller peduncles that connect the cerebellum to brainstem

Question 2

What is the infundibulum?

Answer 2

A narrow hollow stalk that connects the pituitary gland to the hypothalamus

Question 3

What does the cerebral crus connect ?

Answer 3

The midbrain to the cerebellum . Corticospinal fibres travel through the crus

Question 4

What is an epidural haematoma?

Answer 4

Collections of blood in the epidural space between the cranium and the dura mater. The source of bleeding is usually arterial therefore can expand rapidly and cause deterioration of neurological function

Question 5

Subdural haematoma ?

Answer 5

These form in the space between the dura mater and the arachnoid mater . Typically bridging veins are stretched and sheared apart . Haematoma rate is slower than arterial.

Question 6

What are bridging veins ?

Answer 6

The vessels traversing the area in between dura mater and subarachnoid space . They drain venous blood from the surface of the brain coursing the arachnoid and subdural spaces before emptying into the venous sinuses

Question 7

What is a concussion

Answer 7

A temporary disturbance in brain function as a result of trauma

Question 8

What do the semi circular canals do?

Answer 8

Detect angular acceleration of the head /body in three planes .
Gives rise to the vestibulo-ocular reflex and disturbance leads to nystagmus .

Question 9

What do otolith organs do? (Utricle and saccule )

Answer 9

Detect linear acceleration (horizontal and vertical respectively) and orientation in a gravitational field . Detect head or body tilt

Question 10

In vestibular receptors , what causes deflection of the cilia and receptor transduction?

Answer 10

Due to inertia , endolymph lags behind in the semi circular canals during head movement

Question 11

Nerve impulses generated during hair cell activation travel to the brainstem via which cranial nerve

Answer 11

Vestibulo- cochlear

Question 12

What is the purpose of the vesticulo-cochlear reflex?

Answer 12

To stabilise images on the retina during head movements

Question 13

What is caloric stimulation?

Answer 13

Injection of water into the external auditory meatus which leads to heat transfer and sets up convection currents in the horizontal semicircular canal . Fluid movement in the canal stimulates hair cells which activates the vesticbulocochlear reflex . This generates dizziness as a symptom of horizontal nystagmus as a sign of activation of the reflex

Question 14

What conditions can cause vestibular dysfunction?

Answer 14

Labrynthitis and vestibular neuritis (infection) and Ménière’s

Question 15

Primary function of semicircular canals is?

Answer 15

To stabilise images on the retina during head movements via the vestibulo-cochlear reflex .

Excessive stimulation can lead to disorientation and may cause disability

Question 16

Motor Stimulus to test motor skills

Answer 16

Supraorbital notch

Trapezius pinch

Question 17

What does the basal ganglia do?

Answer 17

Influence motor activity and motor control

Question 18

What are the parts of the corpus callosum ?

Answer 18

Posterior - selenium
Middle - body
Anterior - rostrum and genu

Question 19

What does CSF do ?

Answer 19

Affords mechanical and immunological protection to the brain and spinal cord

Question 20

What are the parts of the ventricular system

Answer 20

Body of lateral ventricle 
Aqueduct of midbrain 
Interventricular foramen 
Third ventricle 
Fourth ventricle

Question 21

What makes up the lentiform nucleus

Answer 21

Putamen

Globus pallidus

Question 22

Boundaries of lentiform nucleus ?

Answer 22

Anterior limb
Genu
Posterior limb
Claustrum

Question 23

What type of axons transmit senses from mechanoreceptors of skin

Answer 23

A beta

Question 24

what part of the brain is in control of the declarative memory (fact and events)?

Answer 24

medial temporal lobe ; diencephalonn

Question 25

non declarative memory is controlled where?

Answer 25

procedural memory (skills and habits) - striatum

classical conditioning
skeletal musculature - cerebellum
emotional responses - amygdala

Question 26

what are ballistic movements?

Answer 26

Movement based largely on
a set of pre-programmed
instructions.
• Rapid but at expense of
accuracy – little opportunity
for compensation for
unexpected changes
 e.g. striking a cricket ball,
returning a tennis serve

Question 27

Pursuit or visual feedback

movements ?

Answer 27

Motor command continually
updated according to
sensory feedback (e.g.
visual)

Question 28

what does SMC standfor?

Answer 28

Supplementary motor cortex.

Question 29

what is Proprioception

Answer 29

feedback
from peripheral sensory
receptors on the positions
and movement of limbs -
somatic sensory cortex

Question 30

Lateral pathways:

Main function is

Answer 30

is
control of
voluntary
movement and
distal muscle
groups

Question 31

Ventromedial
pathways:
Mainly control…

Answer 31

proximal and axial
(trunk) muscles
and maintain

Question 32

what is declarative memory

Answer 32

factual info
available to consciousness
easily formed and forgotten
life events

Question 33

non declarative memory

Answer 33

procedural memory
motor skills
not available to consciousness
less easily formed and forgotten

Question 34

what is alpha-synuclein

Answer 34

is a major component of the lewy bodies that are found in the brain tissue in people with parkinsons, mutations in the it cause a very rare , autosomal dominant form of the disease

Question 35

mutations in the protein PARKIN is associated with

Answer 35

an autosomal recessive early onset of parkinsons disease

Question 36

what is the parkinsons tremor

Answer 36

The presenting symptom in 70% of patients. Almost always starts in the fingers and hand and like akinesia, is unilateral initially, spreading later to the leg on the same side and then the opposite arm. The tremor is present at rest and reduces or stops completely when the hand is in motion.

Question 37

parkinsons rigidity

Answer 37

Stiffness on passive limb movement is described as ‘lead pipe’ as it is present throughout the range of movement and unlike spasticity, is not dependent on speed of movement. When stiffness occurs with tremor, a ratchet-like jerkiness is felt, described as cogwheel rigidity.

Question 38

bradykinesia in parkinsons

Answer 38

Slowing of movement (bradykinesia) is the cardinal clinical feature of Parkinsonism and the main cause of disability. What distinguishes it from slowness of movement from other causes is a progressive fatiguing and decrement in amplitude of repetitive movement.s

Question 39

postural instability of parkinsons

Answer 39

A stooped posture is characteristic. Gait gradually becomes shuffling with a small stride length, slow turns, freezing and reduced arm swing. Postural stability eventually deteriorates, leading to falls, but this is a late stage feature which should arouse suspicion of alternative diagnosis if present during the 1st 5 years.

Question 40

speech and writing in parkinsons

Answer 40

can be monotonous at first and progress to slow/weak/ imprecise/ slurring caused by loss of control of muscles involved . dribbling common. writing becomes small and spidery .

Question 41

what is LEVODOPA

Answer 41

it is a precursor for dopamine and is used because dopamine itself cannot cross the blood brain barrier . in the periphery , levodopa is metabolised to dopamine and then to adrenaline /NA which can cause altered blood pressure

Question 42

what is given with Ldopa to stop high blood pressure side effects

Answer 42

it is combined with carbidopa which blocks the conversion of levodopa to dopamine in the periphery thus allowing it to cross the blood brain barrier . other common side effects are nausea and vomiting . it is a dopa decarboxylase inhibitor

Question 43

how do monoamine oxidase b inhibitors work in parkinsons

Answer 43

these reduce the breakdown of dopamine in the CNS , especially the corpus striatum , thus allowing more dopamine to be present . selegilline - prevents MPTP induced neurotoxicity

Question 44

COMT inhibitors

Answer 44

these also prolong dopamine activity by blocking their breakdown . TOLCAPONE

Question 45

dopamine agonists

Answer 45

used in parkinsons .
drug acts directly on the dopamine receptors .
Pramipexole and Ropinirole are D2/3 selective agonists .
main problem is side effects - can cause hallucinations

Question 46

deep brain stimulation to treat parkinsons

Answer 46

involves surgical implantation of high frequency thalamic electrical stimulator that interrupts the tremor causing nerve impulses , minimising dystonia (abnormal muscle tone)