Reading an audience is tricky business, with dividends for those who succeed, and penalties for those who fail.

The reason to stay present and in touch during a presentation, of course, is to ensure a strong connection. Sometimes you’ll need to be agile enough to make mid-course adjustments. Sometimes it’s not necessary.

If the audience seems engaged, stay the course. If listeners seem distracted, you might try ramping up your energy, dropping in a story, or launching a group activity.

Thing is, how can you really know? You can’t very well ask, “Is this boring?” Or, “Is all my jargon giving you a headache?” Or, “Are your phones really that much more interesting than my presentation?”

So you count on your gut, plus the feedback streaming at you from all those faces. For most of what we see from the lectern is faces, and, more specifically, pairs of eyes. We study the eyes and the brows above them because they’re so expressive. They convey interest, delight, sadness, anger, surprise, weariness and lots more.

We think we’re good at reading eyes. Be it social situations, work meetings or peering out from the stage, we think we can tell what people are thinking from their eyes. If you believe you’re among the most literate eye readers, why not test your skills?

The “Mind in the Eyes” test, created by British psychologist Simon Baron-Cohen at the University of Cambridge, shows sets of eyes and asks you to pick from a list of four words per set to describe the person’s emotion. Sounds easy, right?

But are those eyes expressing happiness or surprise? Playfulness or shame? Distrust or indecision?

The test is part of an on-going study that actor Alan Alda mentions in his latest book, a treatise on effective communication called, “If I Understood You, Would I Have this Look on My Face?” Alda’s best tip, by the way, is, “Pay attention to what you’re paying attention to.”

Paying attention to the audience’s mood is smart. Once you take the “eye exam,” however, you’ll realize it’s risky to read eyes and assume you know what the minds behind them are thinking. Assuming boredom, for instance, might unleash your inner critic. Then you’re almost certainly paying attention to the wrong thing. You’ve undercut yourself, when all along the person you thought was bored was just getting over a cold.

Of course there are those who get up and plow through a presentation without ever thinking much about connecting – or staying connected – to their listeners. At some point, they will need to lift their eyes from their text or slides and move on to Advanced Presentation Skills.

Other presenters are making in-the-moment decisions about their audiences all the time. Think about the times you’ve been right, and when you’ve been wrong. Mostly, take heart, for reading a crowd is a skill that will improve with practice and experience.