New York: Dear parents, if you want your child to be mentally fit, Read on. Inadequate night time sleep alters several aspects of children's emotional health, warn researchers.

For the study, published in the Journal of Child Psychology and Psychiatry, the research team studied 53 children ages 7-11 over more than a week. The children completed an in-lab emotional assessment twice, once after a night of healthy sleep and again after two nights where their sleep was restricted by several

"After sleep restriction, we observed changes in the way children experience, regulate and express their emotions," said study lead author Candice Alfano, Professor at the University of Houston in the US.

The multi-method assessment had children view a range of pictures and movie clips eliciting both positive and negative emotions while the researchers recorded how children responded on multiple levels.

In addition to subjective ratings of emotion, researchers collected respiratory sinus arrhythmias (a non-invasive index of cardiac-linked emotion regulation) and objective facial expressions. The researchers pointed out the novelty of these data.

"Studies based on subjective reports of emotion are critically important, but they don't tell us much about the specific mechanisms through which insufficient sleep elevates children's psychiatric risk," Alfano said.

The research team highlights the implications of the findings for understanding how poor sleep might 'spill over' into children's everyday social and emotional lives.

The experience and expression of positive emotions are essential for children's friendships, healthy social interactions and effective coping. "Our findings might explain why children who sleep less on average have more peer-related problems," the study authors said.

Another important finding from the study is that the impact of sleep loss on emotion was not uniform across all children. Specifically, children with greater pre-existing anxiety symptoms showed the most dramatic alterations in emotional responding after sleep restriction."These results emphasize a potential need to assess and prioritize healthy sleep habits in emotionally vulnerable children," the study researchers noted.