- Rods and cones are the photoreceptor cells in the human retina.
- Rods are responsible for letting us see in low levels of light, they don’t regulate color and are not very good at spatial acuity (ie our ability to discern two points in space)
- Cones are active at higher light levels, they are particularly good at spacial acuity and color reception
- *In the back of the eye where the optic nerve pierces the retina, there are no rods and cones
- SO if light from an object lands on this spot* then the object will be invisible to the eye. This is called the optic disc or the blind spot
- We don’t normally perceive the blind spot on a regular basis because our brain interprets the information it receives from our other eye and fills in the needed information to formulate a visual shape.
TRY IT OUT!
Close your right eye, look at the “L” with your left eye, and now move your eye toward or away from the screen until you notice the “R” disappear. Repeat on the other side. Once you move further past the blind spot in either direction, the letter will reappear.