Q. Can you explain why some areas are erogenous and others are not? I know not everyone has the same spots but what makes them erogenous in the first place?
Touching a person creates a sensation from pressure placed on the skin. It is the only one of our senses that we can experience simultaneously with another person.
Beneath the skin's surface are nerve endings which respond to specific types of touch. Some nerve endings or receptors detect pain, others light touch, or cold and still others deep pressure, which seems to override all other sensations. Where these receptors are more dense, stimulation is more pleasurable.
As a survival mechanism our bodies register pleasure when we engage in certain activities (i.e. eating, nursing, sexual intercourse, and defecation). Our brain assumes we are eating when pressure is applied to the lips or tongue, that we are nursing when nipple stimulation occurs and so forth. By this natural process, we are able to become aroused by touching areas of the body other than genitals.
There is a simple test you can try with a hairpin and a ruler to find your most erogenous areas. The tips of the hairpin are spread from two millimeters to seven centimeters in distance and run along the surface of the skin. The object is to determine at which point one can feel the sensation of two pin tips instead of one. The closer the two points can be recognized, the more sensitive the area is to touch. The following is an example of the variances:
tip of tongue 1-2mm
glands of penis 5-9mm
post orgasm 3-4mm