Sensation and PerceptionThe primary function of the senses is to act as biological transducers, devicesthat convert one kind of energy into another. Each sense translates a specifictype of external energy into patterns of activity in neurons. Information arrivingfrom the sense organs creates sensations. Then the brain processes thesemessages. When the brain organizes sensations into meaningful patterns, wespeak of perception.VisionMost people agree that vision is one of the mostimportant senses. And yes, this might be true. Whenyou open your eyes in the morning the first thing yousee is the world that’s around you. Although the visualsystem is much more complex than any other digitalcamera, it still has some similarities. Each one of themhas a lens that helps to focus our vision. In the eyethere is a layer of photoreceptors in the retina which isan area about the size and thickness of a postagestamp.Most focusing is done by the cornea of the eye. Its located on the front part ofit. Our eyes focal point changes when muscles attached to the lens alter itsshape. This process is called accommodation. The eye has two types of imagesensors. It consists in receptors cells called rods and cones. The 5 million cones
