Most people are familiar with and often enjoy visual illusions. The kinesthetic sensory system has its own type of illusions. One type is known as tactile illusions. They relate to the sense of touch. I recall my mother (who loved to wear hats), removing her chapeau at the end of the day and then briefly touching her head with her hand. When I asked her the reason she touched her head she laughed and said, “For a moment it felt as if the hat was still on my head.” Some of you may have experienced a similar illusions. Here's another: Hold one hand in a pan of very cold water and place the other hand in a pan of quite hot water (not hot enough to get burned!). Hold them in this position for at least a minute or two. Now remove both hands and immediately submerge them in lukewarm water. If you’ve done this experiment, you likely found that the lukewarm water felt hot to the hand you had submerged in cold water while the lukewarm water felt cold to the hand you previously immersed in hot water. A tactile illusion.