Visual System (Mixed) Flashcards
Visual area: Nasal receptors in the eye receive information from
Peripheral visual fields
Structure: Important for central vision and visual acuity, bright ligh vision, provides color
Cones
Structure: Most located in the fovea
Cones
Describe where information from the superior and inferior optic radiation are coming from
Superior optic radiations carry information from the inferior visual field
Inferior optic radiations carry infromation from the superior visual field
Structure: Located in the peripheral retina
Rods
Structure: Connections from CN nuclei to the primary visual cortex
Optic radiations
Describe the how rods and cones effect your functionality
Cones: in daylight provide much greater spatial sensitivity in the central retina, however can’t perceive color in our periphery/in low light due to low cone density in the peripheral retina
Rods: In low light we are much more sensitive in our peripheral vision, however in daylight we have poor visual acuity in our periphery
2 Objectives of the Visual System
- Keeping the position of hte eyes stable during head movements so that the environment does not appear to bounce (maintain stable gaze)
- Directing gaze at visual targets
Structure: Receptors that cross in the optic chiasm
Nasal receptors in the eye
Describe how maintaining a stable gaze is achieved
By the VOR: using information from head motion to keep eyes still
By the optokinetic reflex: using visual information to keep eyes still
Describe what can be differentiated between the pupillary reflex and accomodation reflex
Pupillary occurs in the brainstem and is unconscious
Accomodation occurs in the cortex and is conscious
Allows you to differentiate between the location of the problem
Structure: Important for peripheral, low light vision, provides gray scale
Rods
Visual area: Temporal receptors in the eye receive information from
Central visual fields
Structure: Receptors that remain on the same side
Temporal receptors in the eye
