The first child in the family is the smartest

According to the study of more than 250,000 soldiers in Norway, the first children in the family often have higher IQ scores than those who are second-born. The reason is that the first child is better cared for by their parents. Researchers say this difference is due to social factors, not biological factors.

Frank Sulloway, of the University of California, Berkeley, in the US explained that older children in the family may have higher IQs because sometimes they have to replace parents to teach them in some cases.

Another explanation is that parents have more time and more resources for their first baby. Therefore, the first child is more often with the parents and is exposed to the greater intelligence of adults.

Sulloway thinks parents can help raise their children 's IQ by spending more time with each child. The thing will have a higher IQ if they are raised as the first child.

Petter Kristensen, the University of Oslo in Norway, and his colleagues looked at data from soldiers aged 18 and 19 who served in the military from 1985 to 2004. Intelligence index test This is part of the mandatory military service for them.

Researchers then looked at the birth records of these soldiers to see if they were the first or second child. In addition, they also looked at medical records to see if they had siblings who died soon after birth or died when they were very young.

Analysis showed that the first children had an average IQ score of 2.3 points higher than those of the second child. This trend continues when the second child has a higher IQ than the third one, and so on, the third child will have a higher IQ than the fourth one.

TAM HA