Texter 1: Do you still want to get dinner tonight

Texter 2: Sure.

Texter 1: Wait are you actually sure? No worries if you’re busy

Texter 2: Yes.

Texter 1: …is there something you’re not telling me??

If you, too, have experienced the paranoia demonstrated by Texter 1, here’s some validation: Research shows that texts that end with a period really do come off as insincere.

In a study that will be published Feb. 2016 in Computers in Human Behavior, a team of psychologists from Binghamton University showed undergraduate students a series of text exchanges and handwritten notes, and asked them to rate the sincerity of each sender. The messages either contained or left out periods at the ends of sentences.

Participants were significantly more likely to find the senders of period-punctuated texts less genuine than the senders of unpunctuated texts. But when the notes were handwritten, period use didn’t seem to change sincerity ratings.

Short written missives like texts lack contextual clues, such as the real-life facial expressions and speaking volume that usually tell us what a person means beneath what they say. The results of this study suggest that as we shift more toward speedy online exchanges, we may be inventing new ways to convey tone, which include the creative use and interpretation of punctuation.

As corresponding author Celia Klin tells Quartz in an email, “Given that people are so adept at communicating complex and nuanced information in conversations, it’s not surprising that as texting evolves, people are finding ways to convey the same types of information in their texts.”

In a follow-up study, the group found that exclamation points in texts make senders seem more sincere.

It’s important to note that the sample size of 126 was small, US-centric, and contained an overwhelming majority of young female participants. But the study does offer support for the idea that we’re developing new rules in written language to communicate subtleties like passive-aggression.

As with spoken language, expectations are everything; no one judges their parents for sending emails that read like telegrams. Future studies in this area could expand the sample size to be more evenly split by gender, and to include non-native English speakers or people from older generations, to shed light on whether impressions of sincerity change when we know we’re texting people from another demographic.

But what we’d really like to see next is a study about that most baffling text-closer of all…the ellipses.

Image by Intel Free Press on Flickr, licensed under CC BY-SA 2.0.