Cerebrum - sulci and gyri Flashcards
Name the median cleft that separates the 2 hemispheres of the brain.
Longitudinal fissure
The two hemispheres are connected to each
other by a large commissure =
Corpus callosum
Each hemisphere contains an irregular cavity
containing CSF =
Lateral ventricle
What does the cerebrum consist of?
- Grey matter (cortex- externally)
- White matter (internally)
Describe the cerebral cortex
Cortex is thickest in motor area & thinnest at occipital pole (not uniform)
What does the cerebrum have?
The cerebrum has convolutions (gyri) and
these are separated by fissures (sulci) of
varying depth (increase surface area)
What does the white matter consist of?
The white matter consists of nerve fibres which
transmit impulses to and from the cortical nerve
cells and from one cortical area to another
What does the cerebrum enclose?
The cerebrum encloses some larger and smaller masses of
grey matter such as corpus striatum, claustrum,
amygdaloid body
The cerebrum consists of 4 lobes, viz:
❑Frontal
❑Parietal
❑Occipital
❑Temporal
The cerebrum has 3 surfaces, viz:
➢ Supero-lateral
➢ Medial
➢ Inferior
Which sulci divides the supero-lateral surface into the frontal, parietal, occipital and temporal parts?
The supero-lateral Surface is :
Divided into frontal, parietal, occipital and temporal parts by central,
parieto-occipital and lateral sulci
SUPERO-LATERAL SURFACE - Frontal lobe - anteriorly :
superior and inferior frontal sulcus dividing
it to superior, middle and inferior frontal gyri
SUPERO-LATERAL SURFACE - Frontal lobe - posteriorly :
Pre – central sulcus and Pre- central gyrus
the motor area
SUPERO-LATERAL SURFACE - Parietal lobe :
Divided into superior and inferior
parietal lobule by intra-parietal sulcus
SUPERO-LATERAL SURFACE - Temporal lobe :
has the superior & inferior temporal sulci
which divides it into superior , middle &
inferior temporal gyri
SUPERO-LATERAL SURFACE - Occipital lobe :
divided by transverse occipital sulcus and
consists of superior and inferior Occipital gyri
MEDIAL SURFACE - FRONTAL LOBE _ Medial frontal gyrus :
extends above the
cingulate gyrus to the superior border
MEDIAL SURFACE - FRONTAL LOBE _ The central gyrus :
on the medial surface
is a continuation from the supero-lateral
surface and its surrounded by the Paracentral Lobule
MEDIAL SURFACE - PARIETAL LOBE _Paracentral lobule:
part of it behind
the central sulcus
MEDIAL SURFACE - PARIETAL LOBE _ Pre - cuneus :
the area before the
parieto-occipital sulcus
MEDIAL SURFACE - OCCIPITAL LOBE _ The cuneus :
bounded superiorly by the
parieto-occipital sulcus and inferior by
the calcarine sulcus
MEDIAL SURFACE - OCCIPITAL LOBE _ The lingual gyrus :
lies between the calcarine and the collateral sulcus
What does the inferior surface consist of?
smaller anterior and larger
posterior parts
What is medial to the olfactory sulcus?
The gyrus rectus
Where does the olfactory bulb lie?
On the gyrus rectus
Where does the olfactory tract run?
olfactory tract runs in the olfactory sulcus along
side the gyrus rectus
Which sulcus is lateral to the olfactory bulb and sulcus ?
An H - shaped sulcus
The H-shaped sulcus divides the inferior surface of the cerebrum into :
anterior,
posterior, medial and lateral orbital gyri
What is the posterior part[ tentorial area] of the inferior surface partly superior to?
the tentorium cerebelli and
also the middle cranial fossa
What is the posterior part[ tentorial area] of the inferior surface traversed by?
the antero-posterior collateral sulcus
laterally) and occipito-temporal sulcus (medially
What does the lingual gyrus pass into?
the lingual gyrus passes into the
parahippocampal gyrus anteriorly
What does the parahippocampal continue into anteriorly?
anteriorly the parahippocampal gyrus continues
into the uncus
The cerebrum consists of 3 poles, viz :
❑Frontal
❑Occipital
❑Temporal
Which gyrus does the motor function correspond to?
The precentral gyrus
What do the large areas of the motor homunculus represent ?
The muscles
of the hand and face
Which cortex does the postcentral gyrus correspond to?
The primary somatosensory cortex
Where does the Broca’s area or motor speech area lie?
Broca’s area, or the motor speech area, lies just above the lateral sulcus in the frontal lobe
What does the temporal operculum house?
The temporal operculum houses the primary auditory cortex
Where is the visual area situated?
On the posterior pole
and medial aspect of the cerebral
hemisphere in the occipital lobe
In which region is the visual area located?
The region of the
calcarine sulcus
The visual is the…
receiving area for visual
impressions
