Learning orthotactic constraints in typing is similar to, but distinct from, learning phonotactic constraints in speech

Possible spoken and written sequences of a language are determined by phonotactic and orthotactic rules, respectively. Adult speakers quickly learn simple new phonotactic rules (e.g., “/k/ is always an onset in a syllable), but they only learn the more complex second-order rules (e.g., “/k/ is an onset only if the vowel is /æ/, but a coda if the vowel is /ɪ/”) after the first day of training. However, the learning timeline for more complex rules is less consistent across populations and languages. In the current paper, we first show that, in Experiment 1, adults quickly learn new first-order constraints in typing, similar to those in speaking. Next, in Experiment 2, we show that, despite a much higher error rate and opportunities for error-based learning, learning the second-order rules in typing only occurs in the second day, replicating the results of most studies in spoken production. We further discuss that the second-order constraint was learned for the coda, but not the onset, suggesting that learning new rules of sequencing is carried out by a chaining-type mechanism. Lastly, in Experiment 3, we demonstrate that learning new orthotactic constraints in typing is not mediated by phonology, instead, the learning effect is truly orthotactic in nature. Collectively, these data support strong parallels between the statistical learning of orthotactic and phonotactic constraints in language production, despite the differences between spoken and typed modalities of production.