Adolescence is a very complicated period which consistently affects the life and behavior of adolescents. It should be pointed out that it is during this period the behavior of children becomes particularly unpredictable and, what is more, their mood becomes highly changeable.
The behavioral changes that could be observed among adolescents are, to a significant extent, determined by the fact that adolescence is the transitional stage between childhood and adulthood. During this period, adolescents undergo dramatic physiological and psychological change and by the end of adolescent period their identity is practically shaped. On the other hand, such dramatic changes often lead to such serious problems as adolescent depression which results in considerable behavioral change that could observed among teenagers.
On analyzing major problems of the development of children during the period of adolescence, it should be pointed out that basically such problems as adolescent depression are determined by the profound changes which could be observed in behavior of adolescents. At the same time, such changes basically meet the ideas developed by Vygotsky, whose theory stands on the ground that individual passes through several stages of the psychological and physiological development and they may be identified through the development of though and language of individuals. In this respect, the formation of cognitive abilities of adolescents and their speech is often reveal their internal psychological state and may indicate to such a serious problem as depression.
In fact, according to specialists 3-5% of children and adolescents suffer from depression. This problem may reflect the communication and language adolescents use. For instance, often adolescents that suffer from depression refuse to communicate. In this respect, it is important to underline that they tend to avoid the communication not only with their parents or adults that is quite natural for this stage, but also with their peers, even though the inclusion of teenagers in peer groups is of a paramount importance for them. Such an isolation and refusal of communication may be observed in different socio-cultural contexts, but they are particularly unusual in such countries as Japan when the membership and acceptance of a person, especially adolescent, by community is determinant factor of his/her effective socialization. Also, the language of adolescents that suffer from depression is, as a rule quite rude. At any rate, they are not wordy and use short sentences preferring to separate themselves, in such a way, from their social environment.
At the same time, their behavior is highly unpredictable and changeable, especially under the impact of the change in the environment that may be viewed as the Hawthorne effect. Adolescents suffering from depression may change their social behavior and attempt to bridge contacts with a person they feel confident in, but it may occur when this person proves t be able to find some subject for discussion, for instance, which interests the teenager. Finally, it should be said that teenagers suffering from depression feel fatigue and loss of energy practically all the time that leads to their passive behavior, disinterest in social activities, etc.
Thus, adolescent social behavior is characterized by significant changes and sometimes adolescents may suffer from depression, which leads to their isolation, unwillingness to communicate and participate in social activities. However, their behavior may change, at least for short periods of times, as their social environment changes.