1) Purpose of the study
The purpose of this study is to compare and analyze the results of clinical and normal controls through various social and brain medical tests to identify the overall causal relationship of excessive game use for teenagers who are the main targets for game use. 
2) Background and necessity of research
In order to discuss whether game addiction should be defined as a disease and to prepare a diagnostic standard for the disease, one needs to pay attention to the diverse characteristics of game players. Recent research suggests that problem use of games, along with individual development problems, should be considered in combination with both demographic and individual characteristics, which requires a distinct approach to general game users and problem users. The lack of reliable data necessary for game research, which is currently a problem, is due to the fragmentation of game research in various fields, such as medical, clinical psychology and social science, and thus is an integrated study that can support diverse groups. 
Therefore, research on the factors necessary to define the use behavior of game users and the environment and psychological variables is required, including simultaneous study of physical and environmental factors such as neuropsychiatry, clinical psychology, and social science and media. In addition, it is important to analyze brain magnetic resonance imaging (fMRI) results to verify the impact of games on brain function and to identify the relationship between them by examining their neurological status and factors such as physiological examination, home environment, social capital and stress. 
This study will buid the comparative data between excessive game use group and normal use group, identify causal attributes of clinical, environmental, and psychological variables that determine the nature of game use behavior and suggest the social science and medical convergence with a comprehensive causal connection through fMRI, clinical psychology, and social science.

Cohort/Group Label

excessive game use group

Cohort/Group Description

In excessive game use group, middle and high school students scoring higher than 60 in Young internet addiction scale, having problems in home and school, spending 35 hours a week playing game, visiting the department of psychiatry, Chung-Ang University Hospital are targeted.
excessive game use group every years will be conducted psychological scale test and fMRI at 1 year intervals.

Cohort/Group Label

normal group

Cohort/Group Description

In normal group, middle and high school students who are not included in excessive game use group are targeted.
Normal group will be conducted psyhological scale test and fMRI at 1 year intervals

: DNA Collect & Archive: Sample with DNA

blood

middle and high school

In excessive game use group, middle and high school students scoring higher than 60 in Young internet addiction scale, having problems in home and school, spending 35 hours a week playing game, visiting the department of psychiatry, Chung-Ang University Hospital are targeted.
In normal control group, middle and high school students visiting to the departmemt of pediatrics, Chung-Ang University Hospital and recruited through other advertisements are targeted.
The study participants are extracted using non-probablity sampling method.

Gender

Age

Description

In excessive game use group, middle and high school students scoring higher than 60 in Young internet addiction scale, having problems in home and school, spending 35 hours a week playing game, visiting the department of psychiatry, Chung-Ang University Hospital are targeted.

①	Those who have had a history of psychologically diagnosed or are on drugs other than game addiction.
②	Those who are currently suffering from 1 axis and 2 axis mental illness, as a result of the structured interview
③	Those who are the intellectually challenged
④	Those who are diagnosed with congenital genetic disorder
⑤	Person with a history of acquired brain damage, such as cerebral palsy and head trauma
⑥     Person with developmental disabilities, including autism
⑦	Person with speech or learning difficulties
⑧	Those who don't use online (Internet) games or mobile (Mobile) games
⑨	Those who have family members related in the medical profession (intention, doctor, etc.), game company related position, newspaper/ broadcast/media/PR related field, consulting company, market and opinion survey company

Neurocognitive test (K-WISC-IV/K-WAIS-IV)

When participants agree the participate in the study, Neurocognitive test is conducted.

psychological scale test(Comprehensive Scale for Assessing Game Behavior, CSG)

When participants agree the participate in the study, CSG is conducted. Follow-up test is conducted at one-year intervals.

psychological scale test(Young's Internet Addiction Test, YIAS)

When participants agree the participate in the study, YIAS is conducted. Follow-up test is conducted at one-year intervals.

fMRI

When participants agree the participate in the study, fMRI is conducted. Follow-up test is conducted at one-year intervals.

genetic test

When participants agree the participate in the study, Neurocognitive test is conducted.

questions about personal game use, epidemiological survey

When participants agree the participate in the study, question and survey are conducted. Follow-up is conducted at one-year intervals