The sample comprised 542 adolescents with 218 females (40,2%) and 324 males (59,8%). The mean age was 15,5 years. The main experimental group (46 adolescents) included only those respondents who had high levels of Internet addiction combined with the objective data from the questionnaire. The control group consisted of adolescents with no signs of Internet-dependent behavior of comparable age and sex (213 adolescents).

The group of adolescents with Internet-addictive behavior revealed the predominance cyclothymic, labile, asthenoneurotic, sensory, anxiety-pedantic, introverted, excitable, demonstrative and unstable types. We suggest that when characterological traits reach a level of accentuation, that becomes the factor associated with the formation of Internetaddictive behavior. The adolescents with problems of using the Internet show the general emotional instability, the tendency to experience the polar emotions simultaneously; they are excitable and have the aggressive style of communication. One of the main features of their characters is sensitivity to the danger, anxiety that caused the need to escape from the “harsh” reality. It could also be proposed that the adolescents with Internet addictive behavior separate emotions and cognitions, physicality and mentality. They isolate their own feelings and attach greater importance to the intellect. That cause the feeling of themselves as the subjects, more to do with information than with emotions, which could be poorly understood and classified.