Central Visual Pathways
Mason and Kandel
Retinal & Visual Fields
Retinal Fields
Visual Fields
Binocular Field (Zone)
Monocular Fields (Temporal Crescents)
Control of Pupil Size, Eye Position & Movement
Pupil Size is Controlled via the Pretectum & Edinger-Westphal N.
Pathways--
Optic N. →Optic Tr→Pretectum→E.W. N→Oculomotor N→Ciliary G.
(Ciliary G. control pupillary sphinctor muscles)
Clinical Diagnosis of Damage
Eye Position & Movement are Controlled by midbrain Superior Colliculi
Pathways
Optic N→Optic Tr→Sup Colliculus→Frontal Eye Fields
Colliculus→Midbrain + Pons Gaze Centers + Paramedian N.
Colliculus→Spinal Cord (Tectospinal Tract)
Colliculus→Pons (Tectopontine Tract) (To cerebellum)
Anatomy--7 layers
Function--
Make eye + head movements towards stimuli
Interface with auditory, somatosensory, visual & motor information
Maps in Colliculus
Three Sensory and one Motor
Sensory- Visual, Auditory & Somatosensory
Motor
Map Organization
Maps are in register
Arranged relative to proximity to eye (density of fibers↑ closer to eye)
Colliculus Processes Information from--
Motion
Object Outlines
Attentiveness (Visual)
In order to make a saccade and/or head movement
Frontal Eyefields Processes Information from--
Fine Visual Details
Complex Visual Stimuli
In order to make a saccade and/or head movement
