The term procedural knowledge is used in two different ways in the psychological literature. One way that it is used refers to a knowledge of procedures in a specific domain, which could include domains such as mathematics (Rittle-Johnson, Fyfe, & Loehr, 2016), semaphore flag communication (Hung, Hsu, Chen, & Kinshuk, 2015), employees' knowledge of workplace procedures (Schappe, 1996; Leigh & McGraw, 1989) or medical treatments (Higa-McMillan et al., 2017). The second use, which comes from cognitive science, draws from cognitive/neuroscientific theory of language development and use, which contrasts a declarative memory system responsible for fast learning and the use of vocabulary terms in a language with a procedural memory system responsible for deeper, longer term learning and which is believed to underlie the fluent application of grammatical rules to language production (Pinker, 1994; Ullman, 2004; Ullman & Lovelett, 2018).