A series of comparative artificial language learning experiments were conducted to obtain evidence for or against the hypothesis that the mechanism responsible for learning phonological patterns in natural language is distinct from mechanisms responsible for pattern learning in other domains, including natural language syntax (Heinz and Idsardi, 2011, Science). Results from these experiments indicate that the hypothesis is correct. Each experiment examined the learnability of one of three patterns in phonological, syntactic, non-speech auditory, and visual domains. These patterns are significant in different ways: pattern SH is attested in phonology; pattern FL is unattested in phonology; pattern NE is unattested in phonology, but attested in syntax. Results showed that SH was more readily learnable than FL in the phonological and the non-speech auditory conditions, but not the visual condition. Also, the performance of the phonological group was significantly different from the syntax group when exposed to the NE pattern.