Dutchman Bacuna has adapted well to life at Villa Park, and has already found the net twice in 11 appearances since joining from Groningen back in June.
And Lambert believes the 22-year-old's confidence has been key to his good form so far.
"It's important to have a good team spirit and good characters in the building to carry that through, we've certainly got some really good guys," Lambert told the club's official website.
"Leo has come in. He's got that freshness about him.
"At the moment he's playing really, really well for us too. He's hitting the free-kicks like he's done it all of his life.
"I don't think he ever lacks confidence. I haven't had to curtail it.
"He's a really nice guy. He's not arrogant but he's certainly confident, that's for sure."
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