Cerebral Hemisphere

Question 1

Site of 1st somatosensory area

Answer 1

Postcentral sulcus + part of paracentral lobule (B 3,1,2)

Question 2

Body representation of S1 is proportionate to …

Answer 2

Number of receptors in body area

Question 3

Function and lesion of S1

Answer 3

It recieves sensory impulses from2 nuclei of thalamis
Cotralateral hemianesthesia

Question 4

Site and function of S2

Answer 4

S,In superior lip of post. ramus of lateral sulcus
F,Invovled in recognition of hand-held objects by texture and size

Question 5

Describe S2 lesion

Answer 5

Deficits in learning by object manipulation and in recognizing the texture and size of hand-held objects

Question 6

S&F of gustatory area

Answer 6

S, In sup lip of post ramus of latetal sulcus (parietal operculum) extending into the ant part of insula
F, recieces ipsilateral solitario-thalamo-cortical fibers via thalamus

Question 7

Site, Function and lesion of areas 5&7

Answer 7

Superior parietal lobe and precuneus
F, somatosensory association area collects and combines information arriving from multiple areas to understand its meaning.
L, astereognosis

Question 8

S&F of inferior parietal lobule

Answer 8

S, supra marginal gyrus (40) and angular gyrus (area 39)
F, they are parts of Wernicke’s area (sensory speech area) this also incules middle temporal gyrus for comprehension of auditory and visual information then selects suitable words and sends them via the arcuate fasciculus to Broca thus producing speech.

Question 9

Describe lesion of Wernike’s area

Answer 9

Sensory (receptive aphasia), the patient cannot understand spoken or written words thus speaks wrong words but fluently, they do not feel that they have any problem.

Question 10

Define neglect syndrome with giving iys other name

Answer 10

Partial neglect (inattention) to tactile, proprioceptive, and/or visual stimuli delivered from the contralateral side of the lesion site.
Amorphosynthesis

Question 11

Body representation of M1 is proportionate to ….

Answer 11

Skill

Question 12

Describe function and lesion of primary motor area

Answer 12

F, initiates discrete voluntary movements planned in area 6
L, contralateral hemiplegia especially skilled fine movements

Question 13

S,F & lesion of area 6

Answer 13

S, in front of area 4 sup,middle & inf frontal gyri extends on medial surface
F, plans movement, stores the plan, adjusts posture for beginning of movement, inhibit muscle tone & grasp reflex.
L, awkwardeness of movements, spasticity of musckes & reappearance of grasp reflex.
Also called premotor area

Question 14

S&F of frontal eye field

Answer 14

S, in front of area 6 (sup & middle frontal gyri)
F, conjugate voluntary (contra)lateral eye movemets thus to side opposite of its hemisphere

Question 15

Lesion of frontal eye field

Answer 15

Ipsilateral deviation of both eyes & inability to turn eyes to opposite side

Question 16

GR, reflex lat eye movements are not affected in frontal eye field lesion

Answer 16

Because it is controlled by occipital eye field

Question 17

S,F & lesion of Broca’s area

Answer 17

S, pars triangularis (45) & pars opercularis (44) of inf frontal gyrus only in dominant hemisphere
F, contains motor speech area, recieves info from Wernike area then plans proper sequence of contractions to produce speech & sends it to nearby area 4.
L, expressive motor aphasia in which patient have difficulty speaking but selects proper words

Question 18

S&F of supplementary motor area

Answer 18

S, on medial surface of cerebral hemispheres within medial frontal gyrus
F, it stores programmed motor sequences for stereotyped movements also contains a superior speech center
L, temporary akinetic mutism

Question 19

Prefrontal area S,F & lesion

Answer 19

S, remainder of sup, middle & inf frontal gyri + orbital gyri + most of medial frontal gyrus
F, it has a role in intelligence, normal expression of emotion, ability to predict consequences of action also affect behaviour and personality.
L, changes in behaviour, personality & mood