Module 9: age 3-5 years. Learning, developing, and making connections

Question 1

Which part of the eye provides sharp vision?

Answer 1

• The fovea (centre of the macula)
• Has most receptors

Question 2

Which part of the eye senses light and creates electrical impulses that are sent through the optic nerve to the brain.

Answer 2

Retina

Question 3

What is the path of info received from left visual fields?

Answer 3

• Info hits Right side of retina
• Travels through optic chasm to Right lateral geniculate body
• travels to R occipital lobe = primary visual area

Question 4

what eye muscles are enervated by oculomotor Nerve?

Answer 4

• Superior rectus
• inferior rectus
• medial rectus
• inferior oblique

Question 5

Which nerve is lateral rectus supplied by?

Answer 5

• Abducens

Question 6

Trochlear N innervates which muscle?
which direction of vision does this accomodate

Answer 6

• Superior oblique
• In & down
  (medial & inferior)

Question 7

What are the 6 eye movements that keep the fovea on target?
(All eye movements are about foveating)

Answer 7

1. Saccadic
2. Smooth Pursuit
3. Vergence movements - eyes move in opposite directions (disconjugate)
4. Vestibulo-ocular movements
5. Optokinetic movements
6. Fixation system

Question 8

What are the 6 eye movements that keep the fovea on target?
(All eye movements are about foveating)

Answer 8

1. Saccadic
2. Smooth Pursuit
3. Vergence movements - eyes move in opposite directions (disconjugate)
4. Vestibulo-ocular movements
5. Optokinetic movements
6. Fixation system

Question 9

What distance is expected for normal convergence?

Answer 9

• 5cm (5yrs - adult
• 10cm ( 3ys child)

Question 10

Which nucleus is responsible for extra ocular eye muscles innervated by oculomotor N?

Answer 10

• Somatic motor nucleus

Question 11

Which spinal tract controls ipsilateral tone that is referred to in relation to PMRF?

Answer 11

• RETICULOSPINAL tract

**Ipsilateral
- Muscle tone & posture
- tone of respiratory muscles
- FROM reticular formation
- TO LMN ventral horn

Question 12

what drives Pursuit movements?

Answer 12

• Parietal lobe pulls
• same side parietal as direction of pursuit
  eg. pursuit to L = L parietal pulls

Question 13

What drives Saccadic movements?

Answer 13

• Frontal eye field pushes
  eg. Saccade to L = R frontal eye field pushes

Question 14

What eye movements make up OPK movements?
describe what’s happening if checking OPK reflex to L?

Answer 14

• Pursuits (slow phase) & saccades (fast phase)
• L parietal pulls, L cerebellum catches
• L frontal eye fields push & L cerebellum initiates saccade to R
• R cerebellum catches at midline
• pursuit to L initiated by R cerebellum & L parietal pulls

Question 15

Cerebellar tests for 3-5yrs old

Answer 15

• Posture
• gait
• DDK - clapping, fingers, piano fingers
• single leg balance
• Dysmetria