After reading this article you will learn about the Comparison of Taste and Smell Sensations.
I. Chemical Senses:
Both the gustatory sense and the olfactory sense are chemical senses. The action of the stimuli on the sense-organs is chemical in nature. The stimulus of taste is a liquid or a solid substance soluble in saliva. The stimulus of smell is a gas or particles of matter soluble in the air.
There is the phenomenon of adaptation in tastes as well as smells. When we enter a paint shop, we note that the peculiar odour gradually increases in intensity. The salesman hardly notices it because of adaptation. There is adaptation to taste stimuli also.
After eating some sweet-meat we require more sugar to get the desired sweet sensation from tea or coffee. Adaptation indicates the fact that the sensation gradually decreases in intensity with prolongation of a stimulus.
There is successive contrast in taste as well as smell sensation. In both adaptation to one stimulus often increases, the vividness of the response to others. Adaptation to sweet increases responsiveness to sour; adaptation to sour increases sensitivity to sweet; adaptation to salt increases responsiveness to sour and sweet; adaptation to bitter increases sensitivity to sweet.
Adaptation to a foul odour increases responsiveness to fragrant odour. But simultaneous contrast effects, which are apparent in vision, are not so clear in taste and smell.
After-images or after-sensations, though quite common in vision, are also present in taste and smell. If a person feels a ‘hot’ taste, it will linger in his consciousness even after the stimulus ceases to operate on the tongue. This is after-sensation of taste due to the activity of the taste buds.
Similarly, if a person smells a strong perfume, he will continue to feel an after-sensation of smell even after the withdrawal of the stimulus due to continued internal response.
Thus taste and smell sensations agree in the phenomena of adaptation, successive, contrast effects, and after-sensations. They also agree in having a little cognitive value. They have a great affective value. They give us pleasure and pain. Taste and smell sensations cannot be easily revived.