The Blind spot Hannah allen P.4
Photoreceptors *Some are used to detect light while othersAre used to detect the absence of light (note The different colors of the photoreceptors).
*These photoreceptors are arranged in certain ways to help us recognize different objects.
*Each photoreceptor “circle” creates what is known as a receptive Field which is connected to a certain cell in theRetina that gives information to and from the brain allowingus to Know what we are looking at and how bright it is.
The dark ones activate in the absence of light
The light onesactivate in thepresence of light
Why is this important to
know?The reason we have a blind spot in our eyes is because that specific part in our eye is MISSING PHOTORECEPTORS!
IN the optic nerve head, neurons come together & travel in groups through the “photoreceptor sheet” to form the optic nerve! The problem with this is that The optic nerve needs some way pass through eye, thus causing there to be no photoreceptors in the part it exits... this is Where your blind spot is!
Optical nerve head
Center of vision
*Blind spot
Pupil
Retina
Optic nerve
LEFT
Right
THE PartsOfTheEye
Test your blind spot! Cover
your left eye with your hand and stare directly into the
cross... Move your attention
left until the dot disappears
Why don’t you regularly notice your blind spot?
Left eye vision Right eye vision
blind spot
