Toronto, Jun 12 (IANS): Do you use anti-ageing creams? Besides hiding your wrinkles, they may also negatively impact people's perception of your sincerity, say researchers.

The findings showed that human brains are pre-wired to perceive wrinkles around the eyes as conveying more intense and more sincere emotions.

This eye-wrinkle feature, called the Duchenne marker, occurs across multiple facial expressions, including smiles, expressions associated with pain, and expressions of sadness.

When participants were shown images of faces grinning and frowning with and without eye wrinkles, the participants focused on which one their brain deemed most important.

They systematically ranked the Duchenne smiles and Duchenne sad expressions as more sincere and more intense than the non-Duchenne expressions, the researchers said.

"The expressions involving the Duchenne marker were always dominant," said Julio Martinez-Trujillo, Professor at Western University in Ontario, Canada.

"So if the emotion is more intense, your brain actually prefers to bring it into perceptual awareness for longer time."

The results, published in the journal Emotion, are a step toward understanding the more general questions of why facial expressions contain the specific facial actions they do, and how that contributes to our understanding of emotion, the researchers said.

"These findings provide evidence of a potential universal language for reading emotions. In other words, a given facial action may have a single role across multiple facial expressions -- especially if that facial action shapes your social interactions," said Nour Malek from the university.

"My interest now is, what will be the results if we do this same test with people with autism spectrum disorder.

"They often have trouble reading out emotions from other people, so we wonder if that might have to do with their ability to read this marker for sincerity," he said.