Video games are likely to affect the way we behave in a number of ways. For instance, there is concern about whether violence in games makes young people more violent. This is controversial even within the scientific community. Numerous studies about the effects of games on the brain have come up with conflicting results. A team of scientists gathered all scientific articles to date and compared results. In total they found 116 experiments, the first from the 1980s. Many compared regular video game players with people who had never played. Changes in the brain were measured using techniques which detect brain regions increase or reduce in size and these changes affect the brain’s activity. The study found that the clearest negative impact is the risk of addiction, which could affect other brain functions. Games that heavily rely on online multiplayer modes are the most associated with addiction, due to social interactions being more rewarding than just playing against the computer. However, since video games usually display increasing levels of difficulty, they are continually challenging our skills, making the brain perform at 100% of its capacity, resulting in effective cognitive training. Video games also contribute to the proper functioning of the brain, and can even improve it.