6. Cerebrum
The cerebral hemisphere presents:
A. Three surfaces:
1. Superolateral surface.
2. Medial surface.
3. Inferior surface.
B. Three borders:
Superomedial border.
Inferolateral border presents the pre-
occipital notch which is about 5 cm
in front of the occipital pole.
Medial border: which is divided into:
a) Medial orbital border.
b) Medial occipital border.
6neuro anatomy Dr Melad Naim
7. C. Three poles:
Frontal pole.
Occipital pole.
Temporal pole
• Each cerebral hemisphere is divided into 4 lobes :
1. Frontal lobe. 2. Parietal lobe.
3. Temporal lobe. 4. Occipital lobe.
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10. Supero-lateral Surface
Central sulcus:
• The upper end of this sulcus lies almost midway between
the frontal and occipital poles.
• descends downwards on the supero-lateral surface where
it ends above the lateral sulcus.
• extends on the medial surface of the cerebral hemisphere.
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11. Superolateral surface
Lateral sulcus:
consists of a stem and 3 rami.
The stem is present on the inferior surface of the cerebral
hemisphere.
This stem ends on the supero-lateral surface by dividing
into 3 rami.
• Anterior ramus.
• Ascending ramus.
• Posterior ramus.
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12. The main sulci and gyri of the frontal lobe are:
• Precentral sulcus: parallel to and in front of the central sulcus.
• Precentral gyrus:
between the central and the precentral sulci.
extends on the medial surface of the cerebral hemisphere to form part
of the para-central lobule.
corresponds to area 4 of Brodmann.
Functionally, considered as first orprimary somatomotor area. Here,
the body is represented upside down.
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14. Superior and inferior frontal sulci:
• The superior frontal sulcus runs about the middle of the upper
part of the precentral sulcus.
• The inferior frontal sulcus runs below and parallel.
• These two sulci divide this area of the frontal lobe into 3 gyri:
Superior frontal gyrus: Above the superior frontal sulcus.
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15. Middle frontal gyrus: Between the superior and inferior frontal
sulci.
The posterior part of this gyrus presents area 8 which is the main part of
the frontal eye field. (controls conjugate eye movements)
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Inferior frontal gyrus: Below the inferior frontal sulcus.
receives the anterior and ascending rami of the lateral sulcus.
The motor speech area ( Broca's Area) lies on both sides of the
ascending ramus.
concerned with the motor mechanisms of speech (spoken and
written).
17. The main sulci and gyri of the parietal lobe
• Post central sulcus: parallel to and behind the central sulcus.
• Post central gyrus: between the central and the post central sulci.
extends on the medial surface of the cerebral hemisphere to form part
of the para-central lobule.
Functionally it lodges the first or primary somato-sensory area.
the body is represented upside down.
17neuro anatomy Dr Melad Naim
19. • Intraparietal sulcus: behind the post central gyrus dividing that area into
superior and inferior parietal lobules
The superior parietal lobule (somatosensory association area)
The inferior parietal lobule receives the posterior ends of 3 sulci:
1. the posterior ramus of the lateral sulcus which is surrounded by the
supramarginal gyrus.
2. the superior temporal sulcus which is surrounded by the angular gyrus.
3. the inferior temporal sulcus
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21. The main sulci and gyri on the temporal lobe
Superior temporal sulcus:
• parallel to and below the
posterior ramus of lateral
sulcus.
Inferior temporal sulcus:
• parallel to and below the
superior temporal sulcus.
Superior temporal gyrus:
• The auditory area is in the floor
of the lateral sulcus. It extends
into the superior temporal
gyrus below the sulcus, and is
surrounded by the auditory
association area.
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22. The main sulci and gyri on the temporal lobe
Middle temporal gyrus:
• below and parallel to the
superior temporal sulcus.
Inferior temporal gyrus:
• below and parallel to the
inferior temporal sulcus.
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23. The main sulci and gyri on the occipital lobe
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24. The main sulci and gyri on the occipital lobe
• Lunate sulcus: curved sulcus that lies in front of the occipital pole.
• Lateral occipital sulcus: It runs in front of the lunate sulcus dividing that part
of the occipital lobe into superior and inferior occipital gyri.
• The occipital lobe contains areas 17, 18 and 19 which are visual.
• Area 17 is the primary visual area.
• Area 18 and 19: called secondary visual areas or visual association areas.
24neuro anatomy Dr Melad Naim