Master Of Medicine

Frontal Lobe

Primary motor cortex(Ms1)- Area 4, located in precentral gyrus( front of central sulcus)

Premotor area- Area 6 and 8

Prefrontal cortex-9,10,11

Frontal eye field- Common area supplied by premotor area and prefrontal cortex.

Supplementary motor area(MsII)- On medial surface.

Lesions of frontal lobe

MsI- Contralateral hemiplegia

Premotor area-Difficulty to perform skilled movements

MsII-B/L flexor hypotonia

Prefrontal cortex-Also called silent area of brain.Concerned with Intelligence,memory,absract thinking,behaviour,pleasure and displeasure.Involved in depressed fracture of frontal bone.

Frontal eye field-Deviation of eyes to the side of lesion and inability to move eyes to the opposite side(Loss of conjugate eye movements)

Parietal lobe

Primary sensory area(SmI)- Areas 3,1,2

Sensory association area-5,7

Sensory speech area-39,40

Secondary sensorya Area(SmII)-Upperlip of posterior ramus of parietal lobe.

Lesions of parietal lobe

SmI-Loss of appreciation of all sensations from opposite half of body.

SmII-Ablation may relieve intractable pain.

Sensory association area-Tactile agnosia/astereognosis

Wernicke’s area-22,39,40-Sensory aphasia/receptive aphasia.Inability to understand written word(Word blind)

Temporal lobe

Primary auditory area-41,42

Secondary auditory area(Auditary association area)-22

Lesions

Dejavu-due to temporal lobe lesion

b/l lesion-total deafness.

secondary association area-Inability to intepret meanings of words heard(Word deafness)

Psychic Cortex-Anterior part of temporal lobe.In lesions visual and auditory hallucinations develop.Dejavu.Removal of this part leads to deletion of past experiences from memory.

Occipital lobe

Primary visual area-Striate area-area 17

Secondary visual areas/psychovisual areas

• Peristriate area-area 18
• Parastriate area-area 19

Lesions

Primary visual area-Loss of vision in opposite visual field(Crossed homonemous hemianopia)

Secondary visual area-Inabiliy to recognize objects in opposite visual field.

Other areas

Area -44 -Area for taste

Area 28-Olfactory area