Letter repetitions in computer-mediated communication: A unique link between spoken and online language

•The study explores how letter repetitions in CMC (e.g. yessss) are used as cues.•Over 500,000 email messages from the Enron Corpus were analyzed.•It is shown that letter repetitions often, but not always, emulate spoken nonverbal cues.•A longitudinal analysis demonstrates the dynamic nature of the link to spoken cues. Computer-mediated communication (CMC) affords many CMC cues which augment the verbal content of the message: all uppercase letters, asterisks, emoticons, punctuation marks, chronemics (time-related messages) and letter repetitions, to name a few. Letter repetitions are unique CMC cues in that they appear to be a written emulation of a spoken paralinguistic cue – phoneme extension. In this study we explore letter repetitions as a CMC cue, with specific emphasis on elucidating the link between them and spoken nonverbal cues. The letter repetitions are studied in the Enron Corpus, a large ecologically valid collection (∼500,000) of e-mail messages sent by and to employees of the Enron Corporation. We conclude that letter repetitions in the corpus often, but not always, emulate spoken nonverbal cues. This conclusion is examined in a longitudinal analysis that demonstrates the dynamic nature of this cue, and suggests that the usage of letter repetitions is increasing over time, while the link to spoken language is diminishing.