The Role of Conflicting Representations and Uncertainty in Internal Error Detection During L2 Learning

Internal error monitoring as reflected by the error-related negativity (ERN) component can give insight in the L2 learning process. Yet, beginning stages of learning are characterized by high levels of uncertainty, which obscures the process of error detection. We examine how uncertainty about L2 syntactic representations, induced by different levels of language conflict, is reflected in the ERN effect during learning. German learners of Dutch performed a feedback-guided gender decision task in their L2 and were asked to give subjective certainty ratings for their responses. Results indicate that initially, high conflict items yielded more uncertainty and showed an inverse ERN effect, i.e., larger negativities for correct compared to erroneous responses. Two rounds of feedback resulted in an increase of behavioural accuracy, lower levels of uncertainty, and an expected ERN effect, signalling effective error monitoring. These outcomes demonstrate how subjective intuitions about response accuracy affect performance monitoring during L2 learning

Hybridized framing to modify load paths and enhance wood shearwall performance

Heavy timber framing relies primarily on bracing to withstand lateral loads due to earthquakes and wind events. Bracing configurations in heavy timber framed buildings vary widely and include cross bracing, knee bracing, and other geometries. Many heavy timber frames constructed during colonial American times are still standing, exceeding the expected life of many structures being built today. Limited research has been conducted on the lateral resistance of heavy timber frames and their connections and design aids and procedures are not readily available for engineers to assist in the design of these structures. This method of wood construction has been largely replaced with the development of light-framed wood buildings, which utilize sheathing (typically plywood or OSB) attached to the frame to resist lateral loads. Today, the primary form of wood construction is light-frame. These structures rely on shearwalls to resist lateral loads. The shearwall consists of 2x4 or 2x6 studs regularly spaced with wood structural panel sheathing attached to the wall frame. This assembly is lightweight and ductile. Extensive research has been conducted on light-frame shearwalls since the 1950’s. The effects of construction variables (i.e., fastener schedule, sheathing thickness and grade, anchorage, and openings) on shearwall performance have been cataloged through numerous studies. Studies have found the sheathing-frame connection, particularly the perimeter connection, is critical to the performance of a shearwall. This connection is typically nailed, although sometimes staples or adhesives are used. The lateral load path in light-frame shearwalls relies on the sheathing-framing connection. If the load path can be modified then shearwall design can more fully utilize compressive and tensile properties of the wood materials and be less sensitive to the sheathing-framing connection properties. The idea of combining bracing typical of heavy timber framing with techniques used in light-frame construction has not been widely explored by research or analysis. This study investigates the use of bracing in conjunction with light-frame construction (a hybrid framing) to relieve the sheathing nails as the critical load path and enhance the shearwall performance under lateral loading. A 4 by 8-ft. shearwall was designed consisting of an internal cross brace without intermediate framing studs and a lapped connection at the cross intersection. A 4x4 top-plate was used to improve vertical capacity of the braced shearwall because no intermediate stud was included. Four different types of shearwalls were tested under cyclic loading following the CUREE protocol; a conventional light-framed shearwall, a cross-braced shearwall with no mechanical connection at the corners of the walls, a cross-braced shearwall with plywood gusset plates at the corners of the walls, and a cross-braced shearwall with metal truss plates at the corners of the walls. The conventional shearwall and the braced shearwall without mechanical connections at the corner of the wall performed similarly - the sheathing-frame connections controlled their performance. Withdrawal of the sheathing nails was the dominate failure mode. The braced shearwalls with the plywood gusset plate and the metal truss plates at the corners exhibited greater ultimate loads, greater initial stiffness and dissipated more energy compared to the conventional shearwall. The modes of failure for these walls were shear failures in the plywood gusset plates and buckling in the metal truss plates. Some failure was observed in the sheathing nails, however, to a lesser degree than observed in the conventional shearwall. The load path of vertical forces must be addressed in areas where intermediate studs are excluded due to the bracing configuration. Four additional walls were tested under vertical loading; two conventional shearwalls and two cross-braced shearwalls with metal truss plates at the corners. The braced shearwalls proved to adequately resist service level vertical loads similar to those resisted by the conventional shearwall. Overall, using a hybridized shearwall as a part of light-frame construction appears to be viable option to enhance the lateral performance

The uptake of different tillage practices in England

Reduced tillage systems have been argued to provide several potential benefits to soil, environment and to farm incomes. In England, while many farms have partially adopted such practices, a large proportion of arable farmers do not undertake reduced tillage in any form. This paper analyses the rationale for and uptake of different cultivation techniques, including analysis of the barriers to adoption of reduced tillage, aiming to benefit policy makers and researchers and increase the spread of smart agricultural practices. Based on a postal questionnaire, we estimated that 47.6% of English arable land is cultivated using minimum‐tillage and 7% under no‐tillage. As farm size increased, so did the probability of reduced tillage uptake. Furthermore, farms growing combinable crops were more likely to utilise reduced tillage approaches than other farm types. Soil type, weed control and weather conditions were noted as the main drivers for ‘strategic' and ‘rotational' ploughing, constraining continuous reduced tillage use. To effect greater reduced tillage uptake, greater communication between researchers and farmers is needed to facilitate the implementation of sustainable soil management solutions, supported by current legislation permitting responsible herbicide use in arable production. Financial support to access reduced tillage machinery may also be required for farmers operating smaller holdings. Adopting reduced tillage is a continuous learning process requiring ongoing training and information‐gathering; supporting a network of reduced tillage ‘farmer champions' would facilitate practical knowledge exchange, allow farmers to observe soil improvements, understand transition phase barriers, and ultimately encourage increased reduced tillage uptake

Language control in bilingual language comprehension: Evidence from the maze task

Most empirical evidence on switch costs is based on bilingual production and interpreted as a result of inhibitory control. It is unclear whether such a top–down control process exists in language switching during comprehension. This study investigates whether a non-lexical switch cost is involved in reading code-switched sentences and its relation to language dominance with cross-script bilingual readers. A maze task is adopted in order to separate top–down inhibitory effects, from lexical effects driven by input. The key findings are: (1) switch costs were observed in both L1–L2 and L2–L1 directions; (2) these effects were driven by two mechanisms: lexical activation and inhibitory control; (3) language dominance modulated the lexical effects, but did not affect the inhibitory effects. These results suggest that a language control mechanism is involved in bilingual reading, even though the control process is not driven by selection as in production. At the theoretical level, these results lend support for the Inhibitory Control model during language switching in comprehension; while the BIA/BIA+ model needs to incorporate a top–down control mechanism to be able to explain the current findings

Electrophysiological correlates of error monitoring and feedback processing in second language learning

Humans monitor their behavior to optimize performance, which presumably relies on stable representations of correct responses. During second language (L2) learning, however, stable representations have yet to be formed while knowledge of the first language (L1) can interfere with learning, which in some cases results in persistent errors. In order to examine how correct L2 representations are stabilized, this study examined performance monitoring in the learning process of second language learners for a feature that conflicts with their first language. Using EEG, we investigated if L2 learners in a feedback-guided word gender assignment task showed signs of error detection in the form of an error-related negativity (ERN) before and after receiving feedback, and how feedback is processed. The results indicated that initially, response-locked negativities for correct (CRN) and incorrect (ERN) responses were of similar size, showing a lack of internal error detection when L2 representations are unstable. As behavioral performance improved following feedback, the ERN became larger than the CRN, pointing to the first signs of successful error detection. Additionally, we observed a second negativity following the ERN/CRN components, the amplitude of which followed a similar pattern as the previous negativities. Feedback-locked data indicated robust FRN and P300 effects in response to negative feedback across different rounds, demonstrating that feedback remained important in order to update memory representations during learning. We thus show that initially, L2 representations may often not be stable enough to warrant successful error monitoring, but can be stabilized through repeated feedback, which means that the brain is able to overcome L1 interference, and can learn to detect errors internally after a short training session. The results contribute a different perspective to the discussion on changes in ERN and FRN components in relation to learning, by extending the investigation of these effects to the language learning domain. Furthermore, these findings provide a further characterization of the online learning process of L2 learners

Chinese translation norms for 1429 English words

We present Chinese translation norms for 1429 English words. Chinese-English bilinguals (N=28) were asked to provide the first Chinese translation that came to mind for 1429 English words. The results revealed that 71% of the English words received more than one correct translation indicating the large amount of translation ambiguity when translating from English to Chinese. The relationship between translation ambiguity and word frequency, concreteness and language proficiency was investigated. Although the significant correlations were not strong, results revealed that English word frequency was positively correlated with the number of alternative translations, whereas English word concreteness was negatively correlated with the number of translations. Importantly, regression analyses showed that the number of Chinese translations was predicted by word frequency and concreteness. Furthermore, an interaction between these predictors revealed that the number of translations was more affected by word frequency for more concrete words than for less concrete words. In addition, mixed-effects modelling showed that word frequency, concreteness and English language proficiency were all significant predictors of whether or not a dominant translation was provided. Finally, correlations between the word frequencies of English words and their Chinese dominant translations were higher for translation-unambiguous pairs than for translation-ambiguous pairs. The translation norms are made available in a database together with lexical information about the words, which will be a useful resource for researchers investigating Chinese-English bilingual language processing