Depending on the individual, what is felt ranges from very powerful sensations to no sensation at all. Some people feel a tingling, burning or prickling sensation, coldness, draft, pressure, momentary relief, fatigue or drowsiness, uncontrollable laughter or crying, a floating sensation in the extremities, body movement, dizziness or vertigo. Whether or not a patient feels something during therapy, is not an indication of the success of the therapy, because everybody is unique and therefore they react in unique ways.