The study by the University of Miami shows that overly shy preschool children are at greater academic risk than their loud cunterparts.
Researchers found that children displaying shy and withdrawn behaviour early in the preschool year started out with the lowest academic skills and showed the slowest gains in academic learning skills across the year.
"Everybody wants his child to be ready for kindergarten, to know the ABCs and to be able to count, but we often don't understand that having social-emotional readiness is equally important," says Rebecca J Bulotsky-Shearer, assistant professor of psychology at the University of Miami College.
The findings show that behavioural problems in the classroom arise when there is a gap between the child's developmental skills and the expectations of the school environment.
"Preschool children who are very introverted tend to 'disappear within the classroom'," said Elizabeth R Bell, doctoral candidate in developmental psychology at Miami and study co-author.
"It appears that while these children are not causing problems in the school, they are also not engaging in classroom activities and interactions, where almost all learning occurs during this age."
The results also raise the possibility that children who are loud and disruptive may be more likely to get the teacher's attention and benefit from specific educational strategies, according to a Miami statement.
The study is based on an analysis of 4,417 pre-kindergarten children aged three to five years from a diverse population living in a large urban district.
The findings are published in the Journal of 'School Psychology'.
