Men who felt a connection were more likely to laugh and vary their volume (again, showing interest and excitement).
They were less likely to vary their pitch, which the researchers say reflects an attempt to put on a more masculine voice. As Cima of Priceonomics points out, one funny thing about this research is there is an obvious mismatch between the behavior of men and women.
As the researchers note, that may give heterosexual women the upper hand, at least when it comes to first dates.
However, the researchers say the situation could be a little more complex.
What distinguishes a good first date from a bad one?
It's pretty much all on display in the famous double-date scene from "When Harry Met Sally." Sally and her terrible date firmly disagree about important topics.
After the date, the grad students reported how well they "clicked" with their partners for roughly 1,000 four-minute conversations.
The researchers found that physical and character traits, like men's height and shared hobbies, actually had a larger influence on whether couples said they clicked than what they said to each other.
Taken together, these two findings suggest an uneven relationship between men and women: that whether a couple "clicks" is mostly determined by whether the woman is interested in the man, and not vice versa.
At least in this study, these behaviors seem to be an accurate sign of a woman's interest, and men picked up on those signals. First, and perhaps unsurprisingly for people in the dating world, the women were a lot pickier, reporting a sense of connection far less often than men did.
They found that men and women in the study actually altered the pitch of their voice when on a good first date -- basically, taking on a more "masculine" or "feminine" voice when speaking to someone they were interested in.