playing the babies "guitar"... の意味は？

For instance, instead of playing the babies "guitar" and "device", they played "tar" and "vice".
This is a explanation about linguistics. I do not understand the sentence, playing the babies~"device". I've never heard "play + person + object", so
I cannot come up with a good translation. Is it like "having the babies listen to the word "guitar"..."?
言語学に関する実験内容です。playing the babies~"device"の箇所がよくわかりません。play+人+モノは聞いたことがなく訳が思いつきません。「乳児に聞かせた」のような意味でしょうか？