A new study conducted in New Zealand and started in the 1970s has shown a small link between large amounts of TV watching among children and negative behaviors later in life, including aggression, criminality, and anti-social behaviors:
Emerging research suggests that children and adolescents who watch a lot of television are more likely to manifest antisocial and criminal behavior when they become adults.
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Experts then analyzed the data and discovered a small relationship in the data that suggests there is a connection between antisocial personality traits in adulthood and more television watching as a child. The researchers also found that people with a criminal conviction said that they watched more TV as a child compared to those who didn’t have one.
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The study also found that watching more television in childhood was associated, in adulthood, with aggressive personality traits, an increased tendency to experience negative emotions, and an increased risk of antisocial personality disorder, which is characterized by persistent patterns of aggressive and antisocial behavior.