The Blind spotHannah allen P.4

Photoreceptors

*Some are used to detect light while others

Are 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 the

Retina that gives information to and from the brain allowing

us to Know what we are looking at and how bright it is.

The dark ones

activate in the

absence of light

The light ones

activate in the

presence 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

PHOTORECEPTOR

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

LE

FT

Right

THE

Parts

Of

The

Eye

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