Chunking Versus Transitional Probabilities: Differentiating Between Theories of Statistical Learning.

There are two main approaches to how statistical patterns are extracted from sequences: The transitional probability approach proposes that statistical learning occurs through the computation of probabilities between items in a sequence. The chunking approach, including models such as PARSER and TRACX, proposes that units are extracted as chunks. Importantly, the chunking approach suggests that the extraction of full units weakens the processing of subunits while the transitional probability approach suggests that both units and subunits should strengthen. Previous findings using sequentially organized, auditory stimuli or spatially organized, visual stimuli support the chunking approach. However, one limitation of prior studies is that most assessed learning with the two-alternative forced-choice task. In contrast, this pre-registered experiment examined the two theoretical approaches in sequentially organized, visual stimuli using an online self-paced task-arguably providing a more sensitive index of learning as it occurs-and a secondary offline familiarity judgment task. During the self-paced task, abstract shapes were covertly organized into eight triplets (ABC) where one in every eight was altered (BCA) from the canonical structure in a way that disrupted the full unit while preserving a subunit (BC). Results from the offline familiarity judgment task revealed that the altered triplets were perceived as highly familiar, suggesting the learned representations were relatively flexible. More importantly, results from the online self-paced task demonstrated that processing for subunits, but not unit-initial stimuli, was impeded in the altered triplet. The pattern of results is in line with the chunking approach to statistical learning and, more specifically, the TRACX model.

When Gestures Do or Do Not Follow Language-Specific Patterns of Motion Expression in Speech: Evidence from Chinese, English and Turkish.

Speakers of different languages (e.g., English vs. Turkish) show a binary split in how they package and order components of a motion event in speech and co-speech gesture but not in silent gesture. In this study, we focused on Mandarin Chinese, a language that does not follow the binary split in its expression of motion in speech, and asked whether adult Chinese speakers would follow the language-specific speech patterns in co-speech but not silent gesture, thus showing a pattern akin to Turkish and English adult speakers in their description of animated motion events. Our results provided evidence for this pattern, with Chinese-as well as English and Turkish-speakers following language-specific patterns in speech and co-speech gesture but not in silent gesture. Our results provide support for the "thinking-for-speaking" account, namely that language influences thought only during online, but not offline, production of speech.

Cross-linguistic transfer in Turkish-English bilinguals' descriptions of motion events.

Languages differ in how they express motion: Languages like English prefer to conflate manner and path into the same clause and express both elements frequently while languages like Turkish prefer to express these elements separately, with a greater preference for the expression of path of motion. While typological patterns are well-established for monolingual speakers of a variety of languages, relatively less is known about motion expression in bilingual speakers. The current study examined the packaging (expressing each element in separate clauses or within the same clause) and lexical choices (amount and diversity of manner and path verbs) for motion expression in monolingual speakers of Turkish or English and advanced Turkish (L1)-English (L2) bilinguals in a narrative elicitation task. Bilinguals were successful in attaining many English-like patterns of expression in their L2 English but also showed some packaging and lexical choices that were intermediate between English and Turkish monolinguals-thus providing evidence of an L1-to-L2 cross-linguistic effect. Subtle effects of L2 on L1 were also found in bilinguals' lexical choices for the expression of motion in their L1 Turkish. Altogether, our results demonstrate bi-directional transfer effects of learning a typologically distinct language in advanced Turkish-English bilinguals.

Semantic P600-but not N400-effects index crosslinguistic variability in speakers' expectancies for expression of motion.

The expression of motion shows strong crosslinguistic variability; however, less is known about speakers' expectancies for lexicalizations of motion at the neural level. We examined event-related brain potentials (ERPs) in native English or Spanish speakers while they read grammatical sentences describing animations involving manner and path components of motion that did or did not violate language-specific patterns of expression. ERPs demonstrated different expectancies between speakers: Spanish speakers showed higher expectancies for motion verbs to encode path and English speakers showed higher expectancies for motion verbs to encode manner followed by a secondary path expression. Interestingly, grammatical but infrequent motion expressions (manner verbs in Spanish, path verbs and secondary manner expressions in English) elicited semantic P600 rather than the expected N400 effects-with or without post-N400 positivities-that are typically associated with semantic processing. Overall, our findings provide the first empirical evidence for the effect of crosslinguistic variation in processing motion event descriptions at the neural level.

Visual statistical learning is related to natural language ability in adults: An ERP study.

Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities.