"Parents, caregivers and family are the first ones who introduce vocabulary, and the more words the children hear, the greater their vocabulary," said speech language pathologist Judy Montgomery, PhD.
The study also shows that tots who get talked to a lot have higher IQ scores, and do better in school.
But how much talk is enough, and how can parents measure it? Crystal Adams thinks she has the answer -- a small digital processor worn inside her son Ethan's jumper.
"Its counting the words he hears, and then it gives me a good place at the end of the day," said Adam. "I can look at it and say, 'Oh wow, I didn't talk to him as much as I thought I did.'"
The hi-tech device called Language Environment Analysis (LENA) is a kind of verbal thermometer that helps parents gauge how vocal they are with their kids. At the end of the day, you plug the processor into your computer to see how you did.
"It makes graphs," explains Adams. "Then I can look at the graphs, and it tells me how many words he heard throughout the day."
What's the ideal number of words a day? 17,000-to-20,000. And don't think you can plop your child in front of a TV to raise your score.
"The device is designed to screen out or filter out anything that isn't actual speech in that room," said Montgomery.
The manufacturer says the best way to keep the conversational ball rolling is by narrating everything you do with your baby.
The device can also print out a percentile ranking of your kid's progress -- something child care professionals feel might raise unnecessary concerns for anxious parents.