First-born children are more intelligent than their siblings because they receive more mental stimulation in their early years, new research has shown. University of Edinburgh economists found that first-born children achieved higher IQ test scores.
The researchers examined data from 5,000 children. Every child was assessed every two years. The tests included reading recognition, such as matching letters and reading single words aloud. First-born children tended to score higher on verbal, reading, math and comprehension skills.
All children were found to receive the same level of emotional support, but parents appeared to spend less time on brain-stimulating activities with their younger children, took part in fewer activities with them such as reading, crafts and music.
Researchers said the findings could help to explain a phenomenon called the birth order effect which means children born earlier in a family have better wages and higher levels of education later in life.
first-born：形容詞，頭生的，初生的，第一胎的。例句：Charles is their first-born son.（查理是他們第一胎生的兒子。）
nurture：名詞，（後天）養育，培育。例句：The nature versus nurture dilemma is one that scientists have been studying for decades.（先天對上後天的兩難，是科學家數十年來研究的課題之一。）
craft：名詞，技藝，工藝。例句：He learned his craft from an old master.（他從一位老師傅身上學得技藝。）