One good piece of advice I received years ago as a fledgling newsguy was "don't believe any of what you hear and only half of what you see."

Given the impact of human emotion on our ability to interpret what our senses tell us, that was and still is pretty good advice.

A new study out of UCSF shows our emotional state may actually influence what we see. Researchers used a little visual trickery to show participants a continuous string of neutral image faces without the subjects conscious knowledge, while at the same time, a low-contrast image of a smiling, scowling, or neutral face was presented to the participant's non-dominant eye.

At the end of the trial, a set of five faces were shown and participants picked the one that best matched the face they saw during the trial. They were more likely to select faces that were smiling as the best match if the underlying image showed a person who was smiling.

In other words, the subconscious knowledge of "smiling" affected the individuals recognition of others who were smiling as well. Study authors conclude that our emotions are a critical determinant of the experience we create.