Whether you realize it or not, your voice announces your positive or negative emotional state to the entire world. If you feel self-conscious, your listener hears that.

When you feel confident, you communicate authentically. And when you communicate authentically, you sound confident. Confidence and authenticity work together, making your message more fascinating.

Voice cues are subtle and involuntary reflexes, but they broadcast your emotional state to the world.

The iPhone X might make your voice sound better during calls, but your listener's brain can outsmart technology. The human brain evolved to interpret thousands of cues hidden within your voice, in order to interpret your intentions and emotional state.

Marilyn Monroe's voice has been called many things: "Cotton candy, smoke, wind, lollipops and velvet." "Champagne lava." "The slow folding and unfolding of a pink cashmere sweater."

Yet perhaps the most fascinating description of all came from psychologist David Huron: "Wet."

In a series of phone interviews with Dr. Huron, he told me how Marilyn Monroe's voice became a key part of her image: "When we feel confident, when we receive praise, and even when we hug our children, our mouths literally water."

When you feel confident, your mouth produces more saliva. Specifically, your tongue moves more fluidly within the mucous membranes of our mouth. That helps you makes a better first impression, because it communicates that you're on top of your game.

You've experienced this before, even if you don't know it at the time. Let's say you're making a presentation to a big client. Your presentation is going better than expected: nods, smiles, note taking....You're high-fiving yourself inside.

In this moment, your body language exhibits your self-esteem, as do your oral cues. That prospect is consciously listening to what you're saying, but unconsciously listening to how you're saying it.

Not to be a buzzkill, but let's imagine the presentation suddenly takes a major nosedive. Suddenly, the client's face goes tight: "We tried that approach once. It was a major flop." Uh-oh. Your confidence? Gone. Your mouth feels dry, your vocal membranes dehydrating. Your voice becomes tinnier, caused by a blast of fight-or-flight adrenaline.

Instantly, your listeners sense the change in your voice. Their own bodies begin to mirror your stress. Their own brains signal stress. Psychologically, they distance themselves. And just like that, ladies and gentlemen, your confidence has left the building.

To become more impressive and influential, you don't have to sound like Marilyn Monroe. But you do need to sound purposeful. How to do this?

1. Listen to your mouth.

Practice what you have to say.  Record yourself and listen closely to your voice. Are there times when you sound "tinny" or high-pitched? Remember, when your anxiety rises, your brain gets a blast of epinephrine.

Make note of when your voice changes, so that you are aware of the trigger points that make you nervous.

For instance, as Marilyn Monroe taught us, you'll make a stronger first impression if you drink plenty of water when you want to influence your listener. Especially if the message is not an easy one for you to deliver. This helps override the effects of the increased stress hormone.

Your main goal here isn't hydration, it's to prevent dry mouth if you're unexpectedly put on the defensive with negative feedback.

Drink water to prevent that telling "click" in your voice.

2. Fight your fight-or-flight response.

In a state of high stress, your brain easily slides into fight-or-flight mode.

If you can predict the times when you'll feel anxious, you can prevent or compensate for the nervousness that make you sound insecure.

Focus on your posture, body language and breathing, especially if you are feeling anxious. Proper upright posture, with shoulders pulled back, will both boost your inner confidence, while conveying the same to your audience.  Breathe deeply into your diaphragm to avoid becoming short of breath.

3. Go for authenticity over perfection.

Listeners will perceive you as more impressive when you sound authentic, rather than forced. Yet ironically, while you don't want to sound forced, you also don't want to force authenticity.

Authenticity isn't about what you say. It's about who you are.

When you're more relaxed and in your groove, your content and delivery sounds more credible than if your synapses go haywire when you feel freaked out.

These are just a few of the hints we give off every day. These cues either impress your listener, or push them away.

Every time you speak, you say something. But it all starts with your voice.

Think about what your voice says to your listener... and, what it says about you.