Finger pointing is considered rude - but new research shows that the gesture helps preschoolers figure out the world around them.

Across generations and cultures, pointing the finger can be seen as rude and aggressive, even if done to an object.

Pointing can be misconstrued and also attracts attention to a person who probably doesn't want to be the object of curious glances and stares, wrote Emily Post, deceased etiquette expert.

Preschoolers found information more trustworthy when it came from a finger-pointing adult rather than an adult who used other gestures, according to research published Wednesday.

Even when incorrect, the preschoolers trusted the pointers more than adults using other gestures.

Children were willing to attribute knowledge to a person solely based on the gesture they used to convey the information, Carolyn Palmquist, graduate student at the University of Virginia, wrote in a statement. They have built up such a strong belief in the knowledge that comes along with pointing that it trumps everything else, including what they see with their eyes.

The test went like this: Palmquist and her adviser Vikram K. Jaswal showed a video to 48 preschoolers split evenly between girls and boys.

In the video, one woman hid a ball under a cup while the other one covered her eyes and faced the other direction. The children could see where the ball was hidden.

The women then faced the cups and either did nothing, grasped a separate cup or pointed at separate cups.

Preschoolers correctly told researchers the cup with the hidden ball when the women did nothing or grasped a cup. However, when both women pointed at separate cups, the children got the answer wrong half the time.

The power of pointing was so strong, the researchers found, that the gesture overrode what the children had witnessed.

From an early age, when children see pointing, they understand it as an important gesture used in contexts of teaching and learning, Palmquist said. Generally people point because they have good reason to do it.

Pointing is a fundamental gesture, scientists found.

Human beings, of course, find such gestures as pointing and pantomiming totally natural and transparent: just look where I am pointing and you will see what I mean. Indeed, even prelinguistic infants use and understand the pointing gesture, Michael Tomasello, psychology researcher with the Max Planck Institute for Evolutionary Anthropology, writes in the book Origins of Human Communication in 2008.

The research gives an argument that pointing may be useful in helping children with cooperative communication.

This finding fits into that framework. The children are already expecting that people will be helpful and knowledgeable, especially since they're using these cues, Palmquist said.