Ending a text message with a period makes you seem like a jerk, study shows

The world of text-based messaging is no place for proper punctuation, according to a newly released American study — unless, of course, you want to be seen as a jerk.

Researchers from the department of psychology at New York's Binghamton University recently conducted a series of experiments with undergraduate students to explore the role of the period in text messages.

Participants were asked to read 16 different conversations in the form of either texts or handwritten notes. Every exchange included an invitation question (e.g., "Dave gave me his extra tickets. Wanna come?) and an affirmative, one-word response (Sure, Yup, OK, etc.).

After asking the students to rate how "sincere" each reply sounded, researchers noticed a stark contrast in perception between the replies that had a period at the end of them and those that didn't, despite the messages being otherwise identical.

And no, respondents who used periods weren't perceived as being smarter than the others for using proper punctuation.

"Texts that ended with a period were rated as less sincere than those that did not," reads the abstract of the study, which was published last month in the journal Computers in Human Behavior.

Interestingly, no such difference was found for the handwritten notes.

The study's lead researcher, Celia Klin, speculated as to why punctuation marks can hold so much meaning for digital conversations.

"Texting is lacking many of the social cues used in actual face-to-face conversations," she said in a press release issued by the university this week. "When speaking, people easily convey social and emotional information with eye gaze, facial expressions, tone of voice, pauses, and so on."

"People obviously can't use these mechanisms when they are texting," she continued. "Thus, it makes sense that texters rely on what they have available to them — emoticons, deliberate misspellings that mimic speech sounds and, according to our data, punctuation."

While the group of students who participated in the study was relatively small, just 126 undergraduates, Klin and her team's findings appear to be ringing true for many online — though it's being expressed in much harsher terms.

As people reacting to the study on Twitter this week have put it, using a period at the end of a text can make you seem like "a jerk," "heartless," or "probably the worst."

The study's findings aren't groundbreaking, either. Evidence of the "don't end texts with a period" phenomenon could be found online for years before Klin's team published its research.

A New Republic article from 2013 made waves across the blogosphere for its assertion that periods had become "aggressive."

"The period was always the humblest of punctuation marks. Recently, however, it's started getting angry," wrote Ben Crair for the American magazine. "I've noticed it in my text messages and online chats, where people use the period not simply to conclude a sentence, but to announce 'I am not happy about the sentence I just concluded.'"

The New York Times ran a piece in February 2015 with a similar view: "We've begun to think our friends are angry when they respond with a period, or weird when they capitalize the starts of their sentences."

Tweets decrying the use of periods in text messages can be found as far back as 2009.

In followup work that has yet to be published, the Binghamton psychology team explored the role of another contentious punctuation mark: the exclamation point.

The exclamation point was found to make messages seem more sincere, rather than less, as it conveys information about how someone is feeling (enthusiastic, usually, or at least very strongly about something.)

While some in recent years have lamented the rise of the exclamation point as the fall of proper grammar, many digital natives now see it as somewhat neutral — especially in an era of cry-face emojis and Instagram hearts. 

So if you want to spare the feelings of people you text, forget what your elementary school teachers told you about punctuation.

Children of the future may be learning about proper emoji structure at school instead of punctuation.