David Hawker, a psychologist at Keele University, said the most dangerous type of bullying could be overlooked by schools and teachers.
He told the BPS conference that pupils and teachers worried more about physical bullying and rated psychological bullying - such as being shunned by their class-mates - as less serious and upsetting to the victim.
However, a survey of 178 junior (aged 8 to 9) and secondary school children (aged 11 to 12) in six north Staffordshire schools, found that feelings linked to victimisation - depression, anxiety, loneliness, social dissatisfaction and low self-esteem - resulted more from psychological bullying.
It could involve social exclusion from games, parties and outings, or being sent to Coventry by classmates, and the less serious psychological subordination, such as social put-downs, teasing or name-calling. Research suggests that these forms of bullying, particularly social exclusion, appear to have more damaging long-term effects.
Girls were more adept at psychological bullying, through social exclusion of the victim or indirect means, such as social manipulation, or talking behind someone's back, for example. They believed physical bullying was more stressful.
Boys preferred the physical approach, and told researchers that social exclusion worried them more. As both groups got older, psychological methods became the bullying technique of choice.
Previous research suggests that 1 in 10 children is bullied at school, about three per class. Mr Hawker, and his colleague Michael Boulton from the Department of Psychology at Keele said there was growing awareness of bullying in its different forms in schools.
However, children as young as five appeared to accept bullying as a fact of life, and did not believe it could be stopped by rules and regulations.Reuse content