Here, it acts on gene-expression and disrupts brain activity, brain development or both.

ECONOMIST: ADHD and lead

"What we find is that there's correlated activity but that doesn't mean that the production of the facial expression actually causes these changes in the brain, " he says.

WSJ: Stress-Busting Smiles

Most often practised as a communal activity, embroidery strengthens interpersonal relationships and community cohesion, while allowing for individual artistic expression.

UNESCO: MEDIA SERVICES