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Describe the pathway of accommodation reflex

Following are the structures through which light  passes 
Light falls on retina will pass through the following

  • Optic nerve 
  • Optic chiasma 
  • Optic tract 
  • Lateral geniculate body
  • Optic radiation 
  • Occipital cortex
  • Frontal eyefleld area or area 8 through superior longitudinal association tract 
From here fibres descend to the oculomotor nuclei at midbrain as follows .
  • Nucleus for medial rectus  produces medial convergence of eyeball.
  • E W nucleus  produces miosis.
  • Nucleus of Perlia  contraction of cillaris muscle and thus, anterior convexity of lens increases.
  • From oculomotor (E.W) nucleus, the pathway for accommodation reflex is the same as light reflex.
Afferent visual pathway to occipital lobe
  • Frontal lobe
  • Frontal eye fields 
  • Cortico mesencephalic fibers through internal capsule 
  • 3rd cranial nerve nucleus 
  • Medial rectus nucleus and Edinger Westphal nucleus