Cortical Function

Question 1

1. Frontal lobe

Answer 1

• Eye deviation away from side of lesion (frontal eye field lesion)
• Behaviour change
• Primitive reflex - grasp, glabellar, sucking , rooting
• Olfactory loss/ hallucination

2. Parietal lobe:
•  Sensory loss: Astereognosis
•  Loss of 2 point discrimination
•  Sensory inattention
•  Agraphaesthesia
•  Epilepsy 
•  Visual field defect (opposite side)
•  Constructional apraxia

3. Motor cortex
   • Jacksonian epilepsy
   • Motor aphasia (Monoplegia)
4. Temporal lobe
   • Receptive aphasia
   • Upper quadrant anopia - opposite
   • TLE
5. Occipital lobe
   • Homonymous haemianopia
   • Visual hallucination

Question 2

Visual field defect

Answer 2

1. Eye - Blindness involving 1 eye
2. Optic nerve - Blindness involving 1 eye
3. Optic Chiasma - Bitemporal hemianopia
4. Optic tract - Contralateral homonymous hemianopia, spare macula
5. Optic Tract -
   • Parietal lobe (upper fibre) - Quadrantanopia
   • Temporal lobe (lower fibre) - Quadrantanopia
6. Optic radiation - Contralateral homonymous hemianopia, involving macula
7. Occipital lobe - Contralateral homonymous central scotoma

Question 3

Assessment of cortical function

Answer 3

1. Greet the child and talk to him/ her, note the conscious state
2. Speech
   • Ask for spontaneous talk - sex, age , name, address
   • Ask to obey simple commands
   • Ask child to repeat my sentence
   • Name object
   If defective –> Dominant hemisphere defect
3. Test cortical sensory functions
   • Apraxia - to draw a clock
   • Astereognosis - recognise object in hand: key, cube
   • 2 point discrimination
   • Agraphesthesia - recognise figure drawn on palm
   • Sensory inattention
4. Test memory -
   • Both recent and distant, digital reverse
   • Problem solving ability e.g. calculation, etc
5. Note the affect of child
6. Test visual field