Boys with different growth and development and physique, there will be differences in the time of the appearance of physiological reaction, normal development of boys in 11 ~ 13 years old before the appearance of physiological reaction. General boys appear physiological reaction in puberty, if the 5 to 6-year-old boy appeared physiological reaction, usually local stimulation, such as bumping or local stimulation, normal boys almost in 11 to 13 years old. Puberty when androgens began to increase secretion, physiological development will appear laryngeal knot increase, change voice, body hair increase and other manifestations, the specific circumstances according to the individual physical development, there are differences between individuals. Adolescent boys are tempted to stimulate sexual fantasies, there will be a physiological reaction, generally belong to the normal reaction phenomenon.