Motor cortex

Question 1

بسم الله الرحمن الرحيم وبه نستعين
توكلنا علي الحي الذي لا يموت سبحان الله وبحمده كفي به بعبادة خبيرا بصيرا
Dfine cerebral cortex ?

Answer 1

area of cortex responsible for motor functions
1- Primary motor area 4
2-lateral area 6 premotor cortex
3-Medial area 6 supplemental motor area
4-Specialized areas in Premotor cortex

Question 2

Body represenation of Primary motor area
map !

Answer 2

Smoatotopic topographic :
Crossed Inverted
Motor repsesnation :
is disproptionate to actuale muscle sizes but proportionate to skilled motor Value of muscle

Question 3

Area 4 is crossed and inverted function excpet for ?

Answer 3

Respiratory
Abdominal
Head
Upper face muscles
are bilateral Represnted

Question 4

large and small reperesntation in area 4 for?

Answer 4

Large : Tongue + lips + hands
Small : back muscles

Question 5

Explain characters of Area 4

Answer 5

has Betz cells :
Dynamic and static compare!
Dynaminc:
Dishcarge Rapidly for short time + responsible for intiating and dierction of contratcion of muscles
Static : Discharge slowly for long time + responsible for maintatince of force and rate of contraction

Question 6

Connections of Area 4 mention

Answer 6

Area 6
Neocerebellum contralateral
Basal ganaglia
Motor neurons a y of spinal cord pyramidal
motor neuorns a of nuclei of cranial Nerves pyramidal

Question 7

Functions of area 4 ?

Answer 7

1- intiation gine movments Contraction of Distal limb muscles of opposite side
2-share in intiation gross movments contraction of axial and proximal limb muscles of opposite side
3-++Muscle tone
4-++SR and tenodn jerks
5-++superficial refelxes
6-essential for normal Plantar reflex

Question 8

Effect of lesion to area 4 ?

Answer 8

1- loss of fine movement contraction of distal limb muscles in opposited side
2-paresis of gross movment of axial and proximal limb muscles
3-Hypotonia
4-Hyporeflexia
5-loss of abdominal reflex + partial + babinski
6-+partial + babinski dorsifelxion of big toe

Question 9

Mention site and represntation of premotor cortex

Answer 9

lateral area 6 behind the area4
____________
Crossed inverted except eye muscles abdominal and respiratory muscles

Question 10

Connections of area 6 ?

Answer 10

Area 4567
Area 4
Supplemental motor area medial area 6
Area 5,7
Basal gangailia
Paleo Cerebellum
Spinal cord motor nuerons via extrapyramidal tracts

Question 11

Characters of premotor area ?

Answer 11

less Betz
Less excitabel

Question 12

Characters of premotor area ?

Answer 12

less Betz
Less excitable than area 4

Question 13

Functions of Premotor area or lateral area 6 mention

Answer 13

1-Share in gross movments of axial and proximal limb muscles in opposite sides
2-Adjust posture for skilled muscle movments
3-Planning of movments
4-With basal ganglia for automatic unconscious momvmentns as swinging of hand during walk
5-Inhibits muscle tone
6-Inhibits SR and tendon jerks
7-Inhibits Grasp Reflex
8-For Intact plantar reflex

Question 14

Effects of lesion of Premotor cortex lateral area 6 mention

Answer 14

0-Contains memory for Learned motor acts
1-Paresis of Gross movments of axial and proximal limb muscles in opposite side
2-Inability to adjust posture for skilled movments
3-decrease in abilitly of planning movments
4-loss of Automatic unconsous movments
5-hypertonia
6-hyperReflexia
7-grasp Reflex Reappear
8-Partial +Babinski sign and fanning lf lateal 4 toes

Question 14

Effects of lesion of Premotor cortex lateral area 6 mention

Answer 14

0-Inability to perform learned motor acts in absence of paralysis called motor apraxia

1-Paresis of Gross movments of axial and proximal limb muscles in opposite side
2-Inability to adjust posture for skilled movments
3-decrease in abilitly of planning movments
4-loss of Automatic unconsous movments
5-hypertonia
6-hyperReflexia
7-grasp Reflex Reappear
8-Partial +Babinski sign and fanning lf lateal 4 toes

Question 15

سبحان الله وبحمده سبحان الله العظيم
site and representation of the supplemetnal motor area medila area 6

Answer 15

Site anterior and superior to area 6
Representation =Bilateral + Horizontal

Question 16

Functions of Supplemetnal motor area medial area 6 mention ?

Answer 16

Helps in Gross movments which helps in Fine movments
Planning of Complex Bilateral Internally directed
Motor Movments

Question 17

Effect of lesion of Supplemetnal motor area ?

Answer 17

Inability to perform complex motor functions
Inability to perform fine movements or direct and coordinate hands and fingers in bilateral bimanual movments

Question 18

explain broca/s area

Answer 18

spiclaized motor area for storage of programs of vocalization
effect of lesion motor aphasisa

Question 19

Head rotation area ?

Answer 19

Specialized Motor area
for rotation of head without bodu

Question 20

Head rotation area ?

Answer 20

Specialized Motor area
for rotation of head without body

Question 21

Exner,s area ?

Answer 21

Specialized motor area
Hands skills area
for Complex skilled movments with hand
effect of lesion : Agraphia
Incoordinated skilled hand movments but other ordinary are perserved

Question 22

Frontal eye field area 8 ?

Answer 22

fUCNTIONS ?
Contralateral voluntary conjugate eye movments
effect of lesion loss of contalateral voluntary conjugate eye movments
but conjugate eye movments still can be done reflexly
by Tectospinal Tract

Question 23

Area 4
Area 4,6
area 6 supllemtnal motor area

Answer 23

area 4 only intiator of fine movments of hands so lesion cause loss of fine movemetn of hands
4.6 shrares in gross movments so loss of one of them casue paresis of gross movments
Area 6 and supplemental motor area ?
For skilled Movements:-
memory + postural back ground =.=
Lesion cause motor apraxia

Question 24

الحمدلله رب العالمين

Answer 24

الحمدلله حمدا كثيرا طيبا مباركا فيه