The ability to tell apart points that are close together
What type of photoreceptor give low visual acuity?
Rods
What do rods give?
Low visual acuity
Why do rods give low visual acuity?
Because many rods join the same neurone, which means light from two points close together cannot be told apart
what type of photoreceptor gives high visual acuity?
Cones
Why do cones give high visual acuity?
Because cones are close together and one cone joins one neurone
when light from 2 points hits 2 cones, two action potentials (one from each cone) go to the brain- so you can distinguish 2 points that are close together as two separate points
