Child first language and adult second language are both tied to general-purpose learning systems

Abstract

Do the mechanisms underlying language in fact serve general-purpose functions that preexist this uniquely human capacity? To address this contentious and empirically challenging issue, we systematically tested the predictions of a well-studied neurocognitive theory of language motivated by evolutionary principles. Multiple metaanalyses were performed to examine predicted links between language and two general-purpose learning systems, declarative and procedural memory. The results tied lexical abilities to learning only in declarative memory, while grammar was linked to learning in both systems in both child first language and adult second language, in specific ways. In second language learners, grammar was associated with only declarative memory at lower language experience, but with only procedural memory at higher experience. The findings yielded large effect sizes and held consistently across languages, language families, linguistic structures, and tasks, underscoring their reliability and validity. The results, which met the predicted pattern, provide comprehensive evidence that language is tied to general-purpose systems both in children acquiring their native language and adults learning an additional language. Crucially, if language learning relies on these systems, then our extensive knowledge of the systems from animal and human studies may also apply to this domain, leading to predictions that might be unwarranted in the more circumscribed study of language. Thus, by demonstrating a role for these systems in language, the findings simultaneously lay a foundation for potentially important advances in the study of this critical domain.

The effects of working memory and declarative memory on instructed second language vocabulary learning: Insights from intelligent CALL

“…In regard to the former, the present positive findings are in line with previous research that has attested the role of working memory as an important predictor of L2 learning (e.g., Ando et al 1992;Indrarathne and Kormos, 2018;Juff and Harrington, 2011;Linck et al, 2014;Malone, 2018;Yang et al, 2017). Concerning the latter, the results support the theoretical predictions (Ullman, 2015(Ullman, , 2016 that suggest a role for declarative memory in the acquisition of L2 word knowledge (Buffington and Morgan-Short, 2019;Hamrick et al, 2018;Ullman, 2015Ullman, , 2016Ullman and Lovelett, 2018), but contradict earlier labbased research that found no evidence for such a role (Ruiz et al, 2018). However, the association between declarative memory and lexical learning depended on the kind of test used to measure learners' declarative memory abilities.…”

Successful second language learning is tied to robust domain-general auditory processing and stable neural representation of sound

“…Our results, on the other hand, suggest that difficulties with auditory encoding can be a bottleneck for language acquisition both in childhood and later in life. Thus, some of the mechanisms which facilitate language learning may continue to play similar roles throughout the lifespan (Flege et al, 1999;Birdsong & Molis, 2001;Hamrick, Lum, & Ullman, 2018).…”

Seeing problems that may not exist: A reply to West et al.'s (2018) questioning of the procedural deficit hypothesis

“…Moreover, the tasks and analyses they employed throw doubt on whether they even assessed the functionality of procedural memory. Procedural memory is operationalized by the PDH as the implicit learning and memory that relies on a network rooted in the basal ganglia (Evans & Ullman, 2016;Hamrick, Lum, & Ullman, 2018;Ullman, 2004Ullman, , 2016Ullman & Pierpont, 2005). Crucially, on this view procedural memory is not isomorphic with implicit learning and memory.…”