Sensation is the process whereby we receive raw information about the environment from the action of our sense organs. Wilhelm Wundt in 1879 set up the first psychological laboratory in Leipzig, Germany, in order to study sensations. The sensory systems provide our brains with the basic inputs from which our experiences are constructed. We respond to the world as we perceive it not as it is.
Nature of the sensory process
Sensation is the stimulation of sensory receptors to receive information about the outside world. Light, sound, taste, smell, cold, heat, touch, or pain can all produce different sensations. There are eight sense organs and eight corresponding sensations.
The stimulation of the senses is mechanical. It results from sources of energy like light sound, or the presence of chemicals as in smell and taste. Some of these senses work in combination and our response may be a result of this combination. The satisfaction that we enjoy on sipping coffee for example is a combination of the odor and taste of the coffee. Though vision is a very important sense to lives successfully, blind people adapt themselves to their lives and find satisfaction by inventing ways that make them lead successful lives. They channelize the available senses to maximum enjoyment and success in life. The same could be the case with other senses too. The adaptive nature of the sense organs makes life possible in the absence of one or two of those senses. These senses organs function continuously though we may not be aware of their functioning always.
Each sensory channel consists of a sensitive element called the receptor. A receptor is a group of cells specialized to respond to small changes in a particular kind of energy. Each of the receptors responds to a certain kind of physical energy. Sight responds to electromagnetic energy. Hearing responds to mechanical energy sound. Taste or gustatory sense to chemical substances.
Sensation involves a neurological activity. This physical energy which is a stimulus has to be changed into activity within the nervous system. Transduction occurs at the receptors converting physical energy into electrical potential. Each sense organ is connected to a particular part of the brain and that is why the sense-impression (sensation) results.