When you see an object—say, a duck—light in the form of wavelike particles called photons is reflected off the object into your eyes.
At the back of your eyes, your retina has photoreceptor cells that convert light energy into chemical signals that travel to your brain via the firing activity of cells in the optic nerves. These signals are carried to the back of the brain where multiple areas of the visual cortex are engaged. Cells in the area called V1 respond to basic features such as color, motion, and orientation, while other areas contain neural populations that are specialized for more elaborate representations, such as faces. Different neural populations interact to determine what features can be grouped together, as when you perceive both the color of the duck and the shape of its bill. These neural interactions can also fill in gaps in your visual information, as when you can see that the object is a duck even though you can see only part of its bill. The brain manages to tie various features together, so that you don't perceive separately the duck's bill, its color, and its motion, but rather you
see together a white duck with a yellow bill moving down the road.