HNN Topic 4 - Cerebrum

Question 1

Describe the functions of the parietal lobe

Answer 1

• Postcentral gyrus - primary somatosensory area
• Sensory association areas
• Body orientation
• Motor feedback
• Primary gustatory cortex - taste

Question 2

Describe the function of Brocca’s area

Answer 2

Motor aspect of speech

Question 3

Describe the external structure of the cerebrum

Answer 3

• Folded to give sulci (grooves) and gyri (ridges)
• Divided into 2 hemispheres by the longitudinal fissure - runs in median sagittal plane

Question 4

What would be the effect of damage to Wernicke’s area

Answer 4

Receptive aphasia, extremely poor comprehension of speech

Question 5

List the major sulci of the cerebrum

Answer 5

• Central sulcus
• Lateral sulcus
• Luneate sulcus
• Calcarine sulcus

Question 6

Describe the parts of the caudate nucleus

Answer 6

Has an anterior head which is wider, then tapers to a body and posterior tail, with a ‘knee’ (genu) between

Question 7

What is the function of the insular cortex?

Answer 7

Involved in the emotional response to pain

Question 8

Describe the functions of the occipital lobe

Answer 8

• Primary visual cortex
• Visual association area - vision
• Visual interpretation

Question 9

Describe the contents of the internal capsule

Answer 9

• Contains ascending and descending axons, going to and from the cerebral cortex
• Large part is cortiospinal tract - carries motor information from the primary motor cortex to lower motor neurons in the spinal cord

Question 10

Describe the location of the subthalamic nucleus

Answer 10

Inferior to thalamus, above substantia nigra

Question 11

Describe the appearance of the substantia nigra

Answer 11

Dark appearance due to neuromelanin

Question 12

Describe the function of the globus pallidus

Answer 12

Inhibiting muscular activity and reducing muscle tone

Question 13

Describe the internal structure of the cerebrum

Answer 13

• Grey matter - surface of cerebral hemispheres (cortex)
• White matter - deeper parts of brain

Question 14

List the nuclei of the basal ganglia

Answer 14

1. Caudate nucleus
2. Lentiform nucleus - globus pallidus + putamen
3. Substantia nigra
4. Subthalamic nucleus

Question 15

What is the function of the grey matter structures of the cerebrum?

Answer 15

Processing and cognition

Question 16

Describe the structures of the internal capsule

Answer 16

• V shaped
• 3 parts -
  
  • Bend in V = genu
  • Anterior limb
  • Posterior limb

Question 17

Describe the location and function of the corpus callosum

Answer 17

• Wide, thick white matter nerve tract
• Spans part of longitudinal fissure, connecting the cerebral hemispheres
• Forms part of walls of lateral ventricles

Question 18

Describe the function of the putamen

Answer 18

Reinforcement and coordination of learned motor skills

Question 19

Describe the general function of the basal ganglia

Answer 19

Initiate and maintain appropriate motor output

Question 20

List the lobes of the cerebum

Answer 20

• Frontal
• Parietal
• Temporal
• Occipital

Question 21

What would be the effect of damage to Brocca’s area?

Answer 21

Expressive aphasia, non-fluent, slow speech

Question 22

List the major gyri of the cerebrum and their functional significance

Answer 22

• Precentral gyrus - primary motor cortex
• Postcentral gyrus - primary somatosensory cortex
• Superior temporal gyrus - inferior to lateral sulcus, primary auditory cortex

Question 23

What is the function of the white matter structures of the cerebrum?

Answer 23

Connect the grey matter areas

Question 24

Describe the gross structure of the cerebrum

Answer 24

• Largest part of the brain
• 2 cerebral hemispheres - L + R, separated by the falx cerebri of the dura mater
• Separated from cerebellum by tentorium cerebelli

Question 25

Describe the position of the central sulcus

Answer 25

Separates the frontal and parietal lobes

Question 26

List the major white matter bundles of the cerebrum

Answer 26

Internal capsule, corpus callosum

Question 27

Describe the functions of the temporal lobe

Answer 27

* Primary auditory area - hearing * Auditory association area - hearing * Wernicke's area - speech comprehension * Learning and memory (retrieval) * Emotions

Question 28

Describe the location of Brocca's area

Answer 28

* Inferior frontal gyrus (pars opercularis and pars triangularis) * Most commonly in L hemisphere (dominant in 90%)

Question 29

Describe the location of the caudate nucleus

Answer 29

Forms the lateral wall of the lateral ventricles, separated from putamen by white matter fibres (internal capsule)

Question 30

Describe the position of the lateral sulcus

Answer 30

Separates frontal/parietal lobes from the temporal lobe

Question 31

Where are the luneate and calcarine sulci found?

Answer 31

In the occipital lobe, calcarine sulcus marks the position of the primary visual cortex

Question 32

Describe the dorsal and ventral striatum

Answer 32

Dorsal striatum = caudate nucleus + putamen Ventral striatum = olfactory tubercle + nucleus accumbens

Question 34

Describe the function of the caudate nucleus

Answer 34

Sub-control of voluntary movement

Question 35

Describe the location of the internal capsule

Answer 35

Separates the caudate nucleus and thalamus from the putamen and globus pallidus (Lentiform nucleus)

Question 36

Describe the structure of the corpus callosum

Answer 36

4 parts - splenium (posterior), body, genu and rostrum (anterior)

Question 37

Describe the parts of the globus pallidus

Answer 37

Internal and external segments

Question 38

Describe the location of Wernicke's area

Answer 38

Usually in posterior area of superior temporal gyrus, most commonly in L hemisphere

Question 39

Describe the function of Wernicke's area

Answer 39

Sensory language area - lexical processing

Question 40

Describe the main functions of the frontal lobe

Answer 40

* Precentral gyrus = primary motor area (movement) * Motor association area - movement * Primary olfcatory area - smell * Broca's area - motor speech production * Cognitive thought and memory * Control of voluntary movements

Question 41

What are the basal ganglia?

Answer 41

Collection of nuclei strongly associated with the cerebellum, brainstem and cerebral cortex

Question 42

Describe the connections and contents of the corona radiata

Answer 42

* White matter sheet that continues ventrally as the internal capsule * Sheet of ascending and descending axons to and from the cerebral cortex * Fibres radiate out from cortex and come together in the brainstem * Associated w/ corticopontine, corticobulbar and corticospinal tracts

Question 43

Where is the insular cortex found?

Answer 43

Part of cerebral cortex folded deep within the lateral sulcus, lateral to lentiform nucleus

Question 44

Why is the cerebrum folded?

Answer 44

To give a larger surface area to volume ratio