Toddlers who show less fear at the age of three may be more likely to become criminals later in life. Researchers from the University of Pennsylvania studied nearly 1,9000 children born in 1969 and 1970 on the Indian Ocean island of Mauritius. The children were tested on their response to unpleasant noises when they were three and, 20 years later, the researchers looked to see whether they had a criminal record. 137 of the sample did so and compared to the other participants they had a much smaller response to the unpleasant noises at three years old. It could be the case that the children who did not associate unpleasant experiences with fear felt less fear of punishment if they committed a crime. The researchers took into account factors such as parents' education, single parents, socioeconomic status and family size.
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