This is Hermann's Grid. It's a really cool grid that shows how receptive fields and lateral inhibitions. We were just talking about the eye and how light goes into the eye and hits the cones and rods and I was like.. OH! We just learned some stuff about the eye in AP Biology!So basically, neurons in the eye send electrodes to the brain that then interprets the images creating an image in our brain. When light is sensed, action potentials go down the axon if the nerve cells, which transmits the signal to the brain. Action potentials are caused by sodium and potassium flowing into the cell/being actively pumped out. The change in concentration changes the voltage within the cell, which causes the signal to be transfered basically. The axons are insulated with myelin sheaths, which speed up the reactions because less action potentials need to be generated.
Anyways, without going too much into biology, the white intersections have more light falling on it than the white spaces between two black blocks. Lateral inhibition increases visual response by contrast and sharpness. Receptive fields are the space where the photoreceptors respond. The increased luminance in the intersection causes the intersection to appear darker because of the increased inhibition.
So I thought this would be a cool thing to do my journal on, but it involved a lot of biology, which I kind of did know about and some that I did not know about. The physics of this is less of an impact on the illusion, but it is still really cool. When we learned about this in AP bio, I thought it was pretty cool, but then didn't really think about it again. But we started talking about eye stuff in Physics too so I thought, wow, COOOL! Well, sorta.
