The document provides information about the cerebral cortex. It discusses that the cerebral cortex is the outermost layer of the cerebrum and is divided into left and right hemispheres. It plays a key role in functions such as memory, attention, language, and consciousness. The cerebral cortex has six layers and is folded into gyri and sulci. It also describes the different lobes of the cerebral cortex including the frontal, parietal, occipital and temporal lobes. Each lobe has different functional areas that control motor skills, sensory processing, hearing, and other cognitive functions.

1. • Dr.Zulcaif Ahmad
• 03444737311
• Hajvery University
Lahore
12/28/2012 1

2. Physiology
Topic Name:-
Cerebral Cortex
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3. Cerebral Cortex
Introduction:-
• The cerebral cortex is a sheet of
neural tissue that is outermost to
the cerebrum(It is the part of the brain that controls
thought, memory and the senses) of the
mammalian brain. It covers the
cerebrum and cerebellum(Help in maintaining
body's sense of balance.
• Coordinates muscular movements with sensory information)
• , and is divided into left and right
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4. • hemispheres. The cerebral cortex
plays a key role in memory, attention,
awareness, thought, language,
and consciousness.
• In human being , it has an area of 2.2
sq.m.
• The human cerebral cortex is 2–4 mm
(0.08–0.16 inches) thick.
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5. Grey Matter
Grey matter (or gray
matter) is a major
component of
the central nervous
system, consisting
of neuronal cell
bodies, neuropil (den
drites and unmyelinat
ed axons), glial
cells (astroglia and ol
igodendrocytes)
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6. Sulcus
• The surface of the cerebral cortex
is folded in large mammals, such that
more than two-thirds of it in
the human brain is buried in the
grooves, called "sulci“
• depression in the surface of the
brain called sulcus.
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7. Gyrus
• A gyrus (pl. gyri) is a ridge on
the cerebral cortex. It is generally
surrounded by one or
more sulci (depressions or furrows;
sg. sulcus).
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8. 12/28/2012 8

9. Location of cerebral cortex
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10. Layers of Cerebral
Cortex
• Cerebral cortex consists of gray
matter that surrounds the deeper
white matter. It is formed by
different types of nerve cells along
with their processes and neuroglia.
• Cerebral cortex is formed by six
layers of structures.
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11. Layers
1) Molecular or Plexiform
layer
2) External Granular
Layer
3) Outer Pyramidal Layer
4) Internal Granular
Layer
5) Ganglionic Layer or
Internal Pyramidal
layer
6) Fusiform Cell Layer
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12. 12/28/2012 12

13. Diffrence B/W Neocortex and
Allocortex
Neocortex Allocortex
It is the top layer of the • Remaining part of
cerebral hemispheres, cerebral cortex has less
2-4 mm thick, and made than six layers of
up of six layers, labelled structure. The part of
I to VI (with VI being cortex is called
the innermost and I allocortex.
being the outermost) • It includes archicortex
• Neocortex forms the and paleocortex that
major portion of form the part of limbic
cerebral cortex. system.
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14. 12/28/2012 14

15. Cerebral Dominance
• Domaninance of one cerebral
hemisphere over the other in the
control of cerebral function.
(the normal tendency for one half of th
e brain, usually the left
cerebral hemisphere in right-
handed people, to exercise more
control over certain functions (e.g. hand
edness and language)than the other.
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16. Lobes Of Cerebral
Cortex
• In each hemisphere there are three
surface lateral , medial and inferior
surface. The neocortex of each
cerebral hemisphere consists of four
lobes.
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17. Lobes
1)Frontal
Lobe
2)Parietal
Lobe
3)Occipital
Lobe
4)Temporal
Lobe
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18. 1) Frontal Lobe of
cerebral cortex
• The frontal lobe
forms one third of
the cortical
surface. It extend
from frontal pole
to the central
sulcus and limited
below by the
leteral sulcus.
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19. The frontal lobe of cerebral
cortex is divided in to two parts.
1) Precentral
cortex (which is
situated)
posteriorly.
2) Prefrontal
cortex (which is
situated
anteriorly.)
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20. Precental cortex
• The posterior part of frontal lobe is
called precentral lobe cortex.
• Precentral cortex is further divided
in three functional areas.
1) Primary motor area
2) Pre motor area
3) Supplementary motor area
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21. 12/28/2012 21

22. Function of primary
motor area
• Primary motor area is concerned with
initiation of voluntry movements and
speech.
Function of premotor area
The posterior part of the premotor
cortex sends its signals either
directly to the primary motor cortex
to excite specific muscle.
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23. Function of Supplementary
motor area
• The exact function of this area is not
understood clearly.
• It is suggested that it is concern
with the co-ordinated skilled
movements.
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24. Prefrontal cortex
• It is the anterior part of frontal lobe
of central cortex, in front of area 8
and 44.
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25. Function of Prefrontal
cortex
• It forms the center for the higher
functions like emotion , learning ,
memory , and social behavior. short
term memory are register here.
• This area is the seat of intelligence
so it is also called the organ of mind.
• It is responsible for personality of
the individual and various autonomic
changes during emotional condition.
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26. Frontal lobe syndrome
• The injury or ablation of prefrontal
cortex leads to a condition called
frontal lobe syndrome.
• Features:-
• Emotional instability
• Lack of concentration
• Lack of initiation and difficulty in
planning any course of actions.
• Hyperphagia (increased food intake)
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27. 2-PARIETAL LOBE
• Parietal lobe extends from central
sulcus and merges with occipital lobe
behind the temporal lobe below
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28. Parietal lobe are
further divided into
three functional areas
1) Somesthetic area I
2) Somesthetic area II
3) Somesthetic association area
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29. 1) Somesthetic area I
It is also called somatosensory area I
or primary sensory area. It is
present in the posterior lip of central
sulcus.
Function of Somesthetic area I
. Discriminative(diffrence krna) function:-
In addition to perception of cutaneous and
kinesthetic(detects bodily position)
sensation , this area is also responsible for
recognization the discimitive features of
sensation.
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30. • This area sends sensory feedback to
the premotor area. It is also
concerned with the movement of
head and eyeballs.
• It receives sensory impulses from
cutaneous receptor (touch, pressure ,
pain and temperature ).
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31. 2) Somesthetic area II
• It is situated in postcentral gyrus
below the area of face of
somesthetic area I .
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32. Function of Somesthetic
area II
• This area receives sensory impulses
from somesthetic area I and from
Thalamus directly. Though exact role
of this area is not clear , it is
concerned with preception( ) of
sensation.
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33. 3) Somesthetic
Association Area
• This area is situated posterior gyrus
, above the auditory cortex and in
front of visual cortex.
• Function of Somesthetic
Association Area:-
• It is concerned with the synthesis of
various sensation perceived by
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34. somesthetic area I. thus the
somesthetic association area
forms the center for combined
sensation like stereognosis
(understanding the form and
nature of objects by the sense
of touch. The lesion of this
area causes astereognosis (The
inability to determine the form
of an object by touch.)
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35. Parietal lobe syndrome
• Lesion or ablation of parietal
lobe(sensory cortex) results in the
following disturbances
1) Contralateral disturbance of
cutaneous sensation.
2) Disturbances in kinesthetic
sensation.
3) Loss of tactile(the ability to identify, without looking)
localization and discrimination
(understanding diffrence b/w one thing
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and another).

36. Temporal Lobe
• Temporal lobe of cerebral cortex
include three functional area.
1) Primary Auditory area
2) Auditopsychic area
3) Area of equiblirium
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37. 12/28/2012 37

38. 1) Primary Auditory area
• Primary auditory area includes.
1) Area 41
2) Area 42
3) Wernicke’s area
Area 41 and 42 are situated in anterior
transverse gyrus and leteral surface
of superior temporal gyrus.
Wernick’s area in upper part of
superior temporal gyrus posterior to
areas 41 and 42.
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39. Function of Primary
Auditory area
• Primary auditory area is concerned
with perception of auditory impulses ,
analysis of pitch and determination
of intensity and source of sound.
• Area 41 and 42 are concerned only
with perception of auditory impulses.
• Wernicke’s area is responsible for
the interpretation of sound. It
carries out this function with the
help of auditopsychic area (Area 22) 39
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40. 2) Auditopsychic area
• It occupies the superior temporal
gyrus .it is called area 22.
• Functions:-
• This area is concerned with interpretation
of auditory sensation along with
Wernicke’s area.
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41. 3) Area of equiblirium
• This area is the posterior part of
superior temporal gyrus.
• Function:-
• It is concerned with the maintenance
of equilibrium of the body stimulation
of this area causes dizziness, swaying
(rhythmical movement) , falling and
feeling of rotation.
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42. Temporal lobe Syndrome
• It is observed in animal. It occurs in
human being during bilateral lesions
of these structure. The
manifestation of this syndrome are :
• Aphsia ( inability to understand)
• Auditory disturbance
• Disturbance in smell and taste
• Dreamy states
• Visual hallucination (real preception of some thing
which is not present actually).
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43. Occipital Lobe
• Occipital lobe is called the visual
cortex.
• Areas of Visual Cortex:-
1) Primary visual area-area 17
2) Visual association area-area 18
3) Occipital eye field – area 19
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44. Function of Occipital
Lobe
• Primary area-area 17 is concerned
with perception of visual impulses.
• Visual association are-area 18 is
concerned with interpretation of
visual impulses.
• Occipital eye field-area 19 is
concerned with movement of eye.
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45. Occipital lobe syndrome
• Lesion in the upper or lower part of
visual cortex results in hemianopia.
• Bilateral lesion leads to total
blindness.
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46. Cerebral Cortex Lobes
• Frontal Lobes -involved with decision-
making, problem solving, and planning.
• Occipital Lobes-involved with vision
and color recognition.
• Parietal Lobes - receives and
processes sensory information.
• Temporal Lobes - involved with
emotional responses, memory, and
speech
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47. 1.review.ca/I10-80-prefrontal.jpg
www.universe-review.ca
2.8:30 AM
Google Image Result for
http://4.bp.blogspot.com/_aWjmeDtLYpk/TODVISxIYSI/AAAAAAAAAAg/i-
Fo0Um9bCU/s1600/brain3.gif
4.bp.blogspot.com
3.8:29 AM
parts of frontal lobe of cerebral cortex - Google Search
www.google.com.pk
4.
• Morphonix - Brain - Cerebral Cortex: The Thinker
•
Virgil:Basic Neuroanatomy
•
Google Image Result for
http://morphonix.com/software/education/science/brain/g
ame/specimens/images/cerebral_cortex.gif
• 12/28/2012 47

48. • uic.edu/classes/bios/bios100/lecturesf04am/lect22.htm
• www.uic.edu
• 7:37 AM
• Google Image Result for
http://www.uic.edu/classes/bios/bios100/lecturesf04am/ce
rebrum_1.gif
• www.uic.edu
• 7:37 AM
• Google Image Result for http://3.bp.blogspot.com/_G7la-
BXebak/S94bOMmqHwI/AAAAAAAAC04/qo5jIaZsXto/s1
600/cerebral-cortex.jpg
• 3.bp.blogspot.com
• 7:36 AM
• parts of cerebral cortex - Google Search
• www.google.com.pk
• 7:35 AM
• Google Image Result for
http://www.benbest.com/science/anatmind/FigV5.gif
12/28/2012 48
• www.benbest.com

49. Thank You
12/28/2012 So Much 49