"Thank you." These two simple, monosyllabic words mindlessly slip off our tongues every day, almost reflexively.

We utter them so much they've all but become meaningless, out and about, at home and especially at the office, says Dr. Emiliana Simon-Thomas, a veteran neuroscientist, happiness expert and the science director of UC Berkeley's Greater Good Science Center.

If you merely grunt a quick, curt "thank you" to a colleague who just did you a solid, and then say nothing more, you might as well say "thanks for nothing."

Related: 5 Science-Backed Ways to Be Happier at Work

"This one especially applies to bosses, who often feel, 'I don't have to thank my employees because I'm paying them,'" Simon-Thomas tells Entrepreneur during a phone interview. "It goes a long way, starting at the top, where leaders can model gratitude, and not with employee-of-the-month programs that can cause animosity. It could be as simple as taking a few seconds to pop your head into someone's office and properly saying 'thank you' to them for expending their life-energy to make your business successful."

Notice the operative word "properly" there? To properly, sincerely thank your employees like you mean it -- and in ways scientifically shown to increase their happiness and consequently their productivity on the job -- Simon-Thomas says you'd be wise to take the following simple, three-step approach:

1. Say "thanks" or "thank you" -- from the heart.

This is best done face to face -- not by email, tweet, text, Facebook comment or even with a handwritten thank you note, she says.

"When you say 'thank you,' really put your heart into it and think about it, make direct eye contact and do it in a more conscientious, careful way, like you're not just saying two basic words, because you're not," says Simon-Thomas. "It's so much more. You're expressing sincere gratitude."

Bear in mind that Simon-Thomas acknowledges that some people might find it absurd or condescending to be instructed on how to express gratitude. "But we all need a reminder from time to time, particularly if our employees are disengaged," she says. "It's important to remember that superficial, casual thanks that don't mean much don't work for them, nor for anyone, really."

Related: Why Saying 'Thank You' Is More Important Than Giving Employees a Raise

Referencing the work of alternate reality video game developer and gratitude researcher Dr. Jane McGonigal, she also points out that one caringly delivered "thank you" can be contagious throughout the office. Per McGonigal, it packs the potential to spread positivity to up to 258 people.

2. Say what you're thankful for.

Verbally specify the action, achievement or behavior you're grateful for. This is the time to applaud employees and colleagues for something that they did that you want them to do more of, and that you want others to do, too.

"Say thanks for this and fill in the 'this,'" Simon-Thomas says. "'I know this is what you did. I know you put effort into X, Y or Z.' It may sound almost too simple, but it goes a long way."

She offers the apropos example of correctly employing this step to properly thank my editor for editing this article, with an emphasis on specificity and genuineness: "Thank you for doing such a thorough job carefully reading through my work and for giving me that important feedback that I learn from and that benefits our readers."

Related: 5 Simple Ways to Express Gratitude Every Day

3. Connect your thanks to how the person you're thanking influenced you.

Tell the individual you're grateful to specifically how he or she impacted you and what value they provided.

"Doing so really changes the narrative, the feeling of an impression of gratitude," Simon-Thomas says. "Not only does it strengthen camaraderie and cooperation, it also shows the person that you mean what you're saying, that you truly appreciate the value they bring to your work and to the workplace on the whole."

Continuing her example of thanking my editor for closely combing through this article, Simon-Thomas says: "Don't be afraid to dig deeper than the terse, to get a bit personal and admit that you recognize the hard work and effort your editor put into this. You might say, 'Thanks to you, I have now produced a better article than I could have produced on my own. It really made me feel better about the end-product and I wouldn't have been able to do it without you. Thank you for that.'"

Related: Is Your Remote Team in Trouble? Authentic Appreciation Can Help

The result: "They'll likely feel, 'Oh, wow, [my coworker] personally acknowledged me and articulated that I am an important piece of this company. I certainly feel a sense of purpose and I feel essential,'" says Simon-Thomas. "You'll see, they'll give you their best work."