In the classroom, mental imagery seems to be especially important for reading comprehension and learning word meanings, and, according to at least to one theory, is a cornerstone for literacy.
We conducted a secondary analysis on surveys of students who participated in a classroom mental health course taught by their usual teachers.
In contrast, the study conducted in South Korea assessed more than 55,000 children, ages 7 to 12, not only from special education classrooms and mental health service organizations but also regular schools.
Mr Clegg, who is in the city for the Liberal Democrat spring conference, said an average of three children in every classroom had mental health problems that were not being properly identified or supported.
But the deputy prime minister will say that more needs to be done to target help at the young after figures showed that three children in every classroom have diagnosable mental heath conditions.
"The results of this survey suggest schools and young people are often let down and left to fend for themselves," said Paul Burstow MP, chair of the commission, who warned that, on average, about three children in every classroom would experience mental health problems.
Key Findings and Conclusions Observations made in houses and classrooms of children with mental disabilities and those with multiple disabilities found that the caregivers spent more time caring for these children than they did with other children in the family.
So says Ken Smith, author of "Mental Hygiene: Classroom Films 1945-1970".
Three children in every classroom have a diagnosed mental illness, according to the charity YoungMinds.
Friday at 7 p.m. "Mental Hygiene: Classroom Guidance Films 1947-61 "Delinquencyinquency and Diversity".
