Tricking your sense of touch

While looking through my Facebook page I came across a video that was about the sense of touch. The video showed ways of actually tricking your sense of touch. There were four demonstrations in total. The first was writing on a chalkboard. The first time they write they can hear the chalk crunching on the board. The second time they have ear plugs in and say that the board seems much smoother. When the element of sound is taken out the surface seems to be different. The second one is called the imaginary string. This one you clutch your hands together extending your index fingers, and then someone circles their finger around your fingers. They tell you to imagine that they are typing a string around them. Eventually almost against your will they begin to pull together. The third one takes three bowls of water, one hot, cold, and warm. You put one hand in the hot water and the other in the cold. Then take them both out and put them into the warm water, your senses won't be able to tell the difference which hand was in which temperature. And finally the last one involves putting your hand up against another person. While doing this stroke both of the index fingers, this will cause you to feel like your finger is numb. The way your senses can be affected by taking one away or manipulating one is amazing.