Cerebral hemispheres

Question 1

What is the difference between a sulcus and a fissure

Answer 1

Fissure is deeper than a sulcus

Question 2

What are elevations in the cerebral hemispheres called in the cerebrum and the cerebellum Called?

Answer 2

Cerebrum: gyrus Cerebellum: Folia

Question 3

What does the longitudinal fissure divide?

Answer 3

The two cerebral hemispheres

Question 4

what does the central sulcus divide?

Answer 4

The frontal and parietal lobe

Question 5

What does the lateral sulcus/ sylvian fissure

Answer 5

Separates the temporal lobe from the parietal/frontal

Question 6

What does the calcirine fissure divide?

Answer 6

The two occipital lobes

Question 7

What is the insula?

Answer 7

-Small section of the cerebral cortex located in the lateral sulcus -Separates the Frontal and parietal lobes from the temporal lobe

Question 8

What is the principle on which cortical mapping is based on?

Answer 8

Based on the idea that different parts of the brain have different functions as they are histologically different

Question 9

What are the different parts of the cerebrum responsible for?

Answer 9

Anterior Cerebral hemisphere: Motor function of any kind (Frontal)

Posterior Cerebral hemisphere: Sensory function –

• Temporal: smell and hearing
• Parietal: somatosensory (pain, temperature…) -
• Occipital: Vision

Lateral cerebral hemisphere: Limbic function (emotion)

Question 10

What is the difference between a primary area and an associated area?

Answer 10

-Receptors initially send an impulse( based on a detection of change) to the primary areas -Primary areas send info to the adjacent associated areas -Associated areas then process the information and make you aware of what you are feeling

Question 11

Which area are found in the frontal lobe?

Answer 11

Area 4: primary Motor cortex

Area 44,45: Broca’s area

Area 6 is the pre-motor zone

Question 12

Answer 12

Area 4: primary motor cortex

Area 44, 45: Broca’s area

Area 6: Pre-motor zone

Cognition, intellect also controlled in pre-frontal cortex

Question 13

Answer 13

Area 3,1,2: primary sensory cortex

Receives sensory information from contralateral side of body

Superior parietal cortex:

Association area

Interpretation of general sensory information and consciousness

Inferior parietal cortex:

Also known as globule

Interface between primary sensory cortex and the associated cortexes of vision, nose and smell

Only on dominant side contributes to speech

Question 14

Answer 14

Areas 41,42

Primary Auditory cortex

In superior temporal gyrus

Wernicke’s area :

Posterior to primary auditory cortex

Sensory control of speech- crucial for understanding speech

Inferior tract:

Receives sensory information about smell

Question 15

Answer 15

Area 17

Primary vision cortex

On either side of calcimine sulcus

Association area is rest of it

Question 16

Answer 16

Limbic lobe

Hippocampus

Cingulate gyrus

Parhippocampal gyrus

Amygdala

Question 17

What happens when Wernicke’s area is damaged

Answer 17

Cannot make sentences

Cannot understand that what is being said does not make sense

Cannot understand what is being said

Question 18

What happens when Broca’s area is affected

Answer 18

Can still make sense of everything

Cannot formulate speech

Question 19

Which speech area is most likely to be affected by a stroke?

Answer 19

Broca’s as it is found in the frontal cortex

Question 20

What do commisural fibres do?

Answer 20

connect two hemispheres

Question 21

What do projection fibres do?

Answer 21

connect the cerebrum with everything (subcortical centres)

-The neurone pass up to the cerebrum from here through the Corona Radiator

Question 22

what do association fibres do?

Answer 22

connect different part of the hemispheres

• short: from primary to associated
• Long: e.g. from visual cortex to temporal

Question 23

What is the internal capsule?

Answer 23

Collection of white matter which transmits all sensory and Motor information

Question 24

why is the internal capsule usually implicated in strokes?

Answer 24

Its main blood supply is the middle meningeal artery

Question 25

What are the basal ganglia

Answer 25

Collection of neuronal cell bodies in the CNS- should be called basal nuclei

Grey matter

Question 26

What is the function of the basal ganglia

Answer 26

• The caudate nucleus and the putamen are input zones from the pre-motor cortex, the thalamus and the motor cortex
• The output regions are the globus pallidus and the substantial nigra
• The output regions then project back to the thalamus
• They basically are involved in co-ordination of initiation and termination of movements

Question 27

What are the basal ganglia also known as?

Answer 27

The extrapyrimidal system as they are involved in the motor system

Question 28

What makes up the lentiform nucleus?

Answer 28

The globus pallidus and the putamen

Question 29

What does somatotopic mean?

Answer 29

Somatotopic: neurones from a specific area of the precentral gyrus will send impulses to specific part of the body

Lot more neurones to the hand- to allow movement- compared to the rest of the arm as the movements of the hand are a lot more fine tuned.

Depending on how much movement a muscle can perform it will get more or less room on the precentral gyrus