Anatomical features of the brain

Question 1

What is the medulla continuous with?

Answer 1

The spinal hole - through a hole in the base of the skull called the foramen magnum

Question 2

What does the medulla oblongata contain?

Answer 2

1. nuclei for cranial nerves 9-12
2. respiratory and cardiovascular centre
3. ascending and descending neural pathways between brain and spinal cord
4. medullary olives - bundles of neurons connected to cerebellum

Question 3

Why is the medulla important for processing sensory information?

Answer 3

Because several groups of ascending sensory neurons from the spinal cord pass through it

Question 4

Neurons carrying sensory information about what pass through the medulla?

Answer 4

1. texture, grip and joint position
2. pain
3. temperature

Question 5

What is the pathway of neurons carrying sensory information about texture, grip, and joint position?

Answer 5

1. Up spinal cord
2. Synapse in posterior medulla
3. Cross over and go up to thalamus and contralateral sensory cortex

Question 6

What is the pathway of neurons carrying sensory information about pain?

Answer 6

1. up spinal cord
2. synapse in medulla or pons in reticular formation
3. go up to thalamus and contralateral sensory cortex

Question 7

What is the pathway of neurons carrying sensory information about temperature?

Answer 7

1. travel up spinal cord
2. through medulla but do not synapse there
3. synapse in thalamus

Question 8

What descending neurons pass through the medulla?

Answer 8

motor neurons from the motor cortex

Question 9

What do motor neurons form in the medulla?

Answer 9

Two ridges on the anterior surface on the midline known as the ‘pyramids’

Question 10

What do the medullary olives do?

Answer 10

Communicate with the cerebellum to help control movement

Question 11

Where is the pons?

Answer 11

The middle section of the brainstem bridging between the two halves of the cerebellum

Question 12

What does the pons contain?

Answer 12

1. axons linking the two halves of the cerebellum
2. axons linking cerebral cortex and spinal cord
3. cranial nerves 5 and 6

Question 13

Which important pathways does the pons contain?

Answer 13

1. sensory axons travelling up from spinal cord
2. sensory axons travelling across and up from cochlear nuclei to auditory cortex to form the lateral lemniscus
3. motor axons travelling down to the spinal cord form the pyramidal tract anteriorly

Question 14

What does the midbrain contain?

Answer 14

1. cerebral penduncles anteriorly
2. tectum posteriorly
   The areas are separated by and imaginary line through the cerebral aqueduct

Question 15

What are the cerebral penduncles made up of?

Answer 15

1. motor axons travelling down from the cortex to the brainstem and spinal cord
2. sensory axons travelling up from brainstem and spinal cord to cortex

Question 16

What is the tectum made up of?

Answer 16

1. superior colliculi
2. inferior colliculi

Question 17

What does the superior colliculi do?

Answer 17

coordinates eye and head movements to follow objects in a visual fieldW

Question 18

What do the inferior colliculi do?

Answer 18

Centres for coordination of auditory reflexes to turn the head towards a sound source

Question 19

Which important pairs of nuclei are found in the anterior part of the midbrain?

Answer 19

1. red nuclei
2. substantia niagra

Question 20

What do the red nuclei do?

Answer 20

Connect the cerebellum with descending motor pathways

Question 21

What do the substantia niagra do?

Answer 21

Part of the basal nuclei involved in movement control

Question 22

What is the cerebellum involved in?

Answer 22

1. control of motor activity (rate, range, and force)
2. learning motor skills
3. balance

Question 23

What do the cerebellar peduncles connect the cerebellum to?

Answer 23

1. cerebral hemispheres - superior cerebellar peduncles
2. pons - middle cerebellar peduncles
3. medulla oblongata - inferior cerebellar peduncles

Question 24

Which parts of the cerebellum have developed over the course of evolution?

Answer 24

1. flocculondular lobe (vestibulocerebellum)
   2 spinocerebellum/vermis
2. cerebrocerebellum

Question 25

What does the flocculonodular lobe do?

Answer 25

1. receives input from the vestibular nuclei in the pons and medulla via the inferior cerebellar peduncles
2. sends efferent info back to vestibular nuclei and then to descending motor neurons
3. primarily concerned with balance

Question 26

What is the role of the spinocerebellum?

Answer 26

Influences muscle tone and posture through spinal motor nerves

Question 27

What inputs and outputs are in the spinocerebellum?

Answer 27

1. majority of inputs are from neurons carrying proprioceptive info from muscles and joints
2. major outputs are the red nucleus in midbrain - muscle contraction and joint control
3. input and output mainly via superior cerebellar peduncle

Question 28

What are the main inputs of the cerebrocerebellum?

Answer 28

1. areas of the cerebral cortex involved in planning and execution of movement
2. connect to the cerebellum via the pons through the middle cerebellar peduncles

Question 29

What are the main outpputs of the cerebrocerebellum?

Answer 29

1. red nuclei in midbrain
2. thalamus -> motor cortex
3. most axons exit through the superior cerebellar peduncles

Question 30

What are the basal ganglia?

Answer 30

System of nuclei located deep in each cerebral hemisphere (corpus striatum) and the midbrain

Question 31

What makes up the basal ganglia?

Answer 31

1. caudate nucleus
2. lentiform nucleus
3. substantia niagra