Typing /s/—morphology between the keys?

Morphological structure exerts an influence on acoustic duration. But does it also influence typing duration? The present article reports an experimental study that tests for the influence of morphological structure on typing timing. It is also a first of its kind comparison between spoken and written language production within the same paradigm, which explores the extent to which a pattern that has been found for speech production may have an analogue in written language production. In an online typing study using the experimental design of Schmitz et al. (Phonetica 78:571–616, 2021a), we test their results from the spoken domain for transferability to the written domain. Specifically, our study investigates whether language users type word-final < s > in English pseudowords at different word-internal boundaries—non-morphemic, plural, auxiliary has-clitic and is-clitic—with differing speeds and how our results compare to those found by Schmitz et al. (Phonetica 78:571–616, 2021a) for articulation. We find that the influence of morphological structure on articulation and typing timing does not follow an identical principle. While durational differences are found for the different morphological categories in articulation, participants in our experiment type non-morphemic < s > and plural < s > at almost identical speed. A significant difference emerges, however, for the typing of auxiliary clitics. Our results suggest that processing units other than morphemes might be dominant in written language production.