Contextual diversity facilitates learning new words in the classroom.
ABSTRACT: In the field of word recognition and reading, it is commonly assumed that frequently repeated words create more accessible memory traces than infrequently repeated words, thus capturing the word-frequency effect. Nevertheless, recent research has shown that a seemingly related factor, contextual diversity (defined as the number of different contexts [e.g., films] in which a word appears), is a better predictor than word-frequency in word recognition and sentence reading experiments. Recent research has shown that contextual diversity plays an important role when learning new words in a laboratory setting with adult readers. In the current experiment, we directly manipulated contextual diversity in a very ecological scenario: at school, when Grade 3 children were learning words in the classroom. The new words appeared in different contexts/topics (high-contextual diversity) or only in one of them (low-contextual diversity). Results showed that words encountered in different contexts were learned and remembered more effectively than those presented in redundant contexts. We discuss the practical (educational [e.g., curriculum design]) and theoretical (models of word recognition) implications of these findings.
Project description:Visual context facilitates perception, but how this is neurally implemented remains unclear. One example of contextual facilitation is found in reading, where letters are more easily identified when embedded in a word. Bottom-up models explain this word advantage as a post-perceptual decision bias, while top-down models propose that word contexts enhance perception itself. Here, we arbitrate between these accounts by presenting words and nonwords and probing the representational fidelity of individual letters using functional magnetic resonance imaging. In line with top-down models, we find that word contexts enhance letter representations in early visual cortex. Moreover, we observe increased coupling between letter information in visual cortex and brain activity in key areas of the reading network, suggesting these areas may be the source of the enhancement. Our results provide evidence for top-down representational enhancement in word recognition, demonstrating that word contexts can modulate perceptual processing already at the earliest visual regions.
Project description:Vocabulary learning occurs throughout the lifespan, often implicitly. For foreign language learners, this is particularly challenging as they must acquire a large number of new words with little exposure. In the present study, we explore the effects of contextual diversity-namely, the number of texts a word appears in-on native and foreign language word learning. Participants read several texts that had novel pseudowords replacing high-frequency words. The total number of encounters with the novel words was held constant, but they appeared in 1, 2, 4, or 8 texts. In addition, some participants read the texts in Spanish (their native language) and others in English (their foreign language). We found that increasing contextual diversity improved recall and recognition of the word, as well as the ability to match the word with its meaning while keeping comprehension unimpaired. Using a foreign language only affected performance in the matching task, where participants had to quickly identify the meaning of the word. Results are discussed in the greater context of the word learning and foreign language literature as well as their importance as a teaching tool.
Project description:Word learning can build the high-quality word representations that support skilled reading and language comprehension. According to the partial knowledge hypothesis, words that are partially known, also known as "frontier words" (Durso & Shore, 1991), may be good targets for instruction precisely because they are already familiar. However, studies investigating this question have produced mixed findings, and individual differences in baseline knowledge have complicated results both within and across studies. We present two studies that took a different approach, controlling both familiarity and the nature of the familiarizing episode. We controlled familiarity with novel words through pre-exposure ("pre-familiarization") in isolation, to induce form-based familiarity, or in sentences that provided few clues to meaning, to induce partial semantic knowledge. The number of pre-exposures varied (0, 1, or 4). After the pre-familiarization phase, we presented the words in several highly informative sentences to support meaning acquisition. Participants included both adults and typically developing children, ages 9-12. Participants' self-rated familiarity with target words, and their knowledge of the words' meanings and orthography were each measured at baseline, immediately after learning, and one week later. Orthographic and semantic word learning showed contrasting effects of pre-familiarization. For orthographic learning, it was the number, rather than the type, of pre-familiarizations that mattered most. By contrast, the number of pre-familiarizations had little impact on word semantic learning; further, pre-familiarization in low-constraint sentences did not consistently boost subsequent learning. These findings suggest that familiarity with a word prior to instruction does not necessarily improve word-learning outcomes, and they highlight the importance of repeated exposures to high quality contexts for robust word learning.
Project description:Words are considered semantically ambiguous if they have more than one meaning and can be used in multiple contexts. A number of recent studies have provided objective ambiguity measures by using a corpus-based approach and have demonstrated ambiguity advantages in both naming and lexical decision tasks. Although the predictive power of objective ambiguity measures has been examined in several alphabetic language systems, the effects in logographic languages remain unclear. Moreover, most ambiguity measures do not explicitly address how the various contexts associated with a given word relate to each other. To explore these issues, we computed the contextual diversity (Adelman, Brown, & Quesada, Psychological Science, 17; 814-823, 2006) and semantic ambiguity (Hoffman, Lambon Ralph, & Rogers, Behavior Research Methods, 45; 718-730, 2013) of traditional Chinese single-character words based on the Academia Sinica Balanced Corpus, where contextual diversity was used to evaluate the present semantic space. We then derived a novel ambiguity measure, namely semantic variability, by computing the distance properties of the distinct clusters grouped by the contexts that contained a given word. We demonstrated that semantic variability was superior to semantic diversity in accounting for the variance in naming response times, suggesting that considering the substructure of the various contexts associated with a given word can provide a relatively fine scale of ambiguity information for a word. All of the context and ambiguity measures for 2,418 Chinese single-character words are provided as supplementary materials.
Project description:Prior research has examined how distributional properties of contexts (number of unique contexts or their informativeness) influence the effort of word recognition. These properties do not directly interrogate the semantic properties of contexts. We evaluated the influence of average concreteness, valence (positivity) and arousal of the contexts in which a word occurs on response times in the lexical decision task, age of acquisition of the word, and word recognition memory performance. Using large corpora and norming mega-studies we quantified semantics of contexts for thousands of words and demonstrated that contextual factors were predictive of lexical representation and processing above and beyond the influence shown by concreteness, valence and arousal of the word itself. Our findings indicate that lexical representations are influenced not only by how diverse the word's contexts are, but also by the embodied experiences they elicit.
Project description:Purpose Retrieval practice has been found to be a powerful strategy to enhance long-term retention of new information; however, the utility of retrieval practice when teaching young children new words is largely unknown, and even less is known for young children with language impairments. The current study examined the effect of 2 different retrieval schedules on word learning at both the behavioral and neural levels. Method Participants included 16 typically developing children ( M TD = 61.58 months) and 16 children with developmental language disorder ( M DLD = 59.60 months). Children participated in novel word learning sessions in which the spacing of retrieval practice was manipulated: Some words were retrieved only after other words had been presented (i.e., repeated retrieval that required contextual reinstatement [RRCR]); others were taught using an immediate retrieval schedule. In Experiment 1, children's recall of the novel word labels and their meanings was tested after a 5-min delay and a 1-week delay. In Experiment 2, event-related brain potentials were obtained from a match-mismatch task utilizing the novel word stimuli. Results Experiment 1 findings revealed that children were able to label referents and to retain the novel words more successfully if the words were taught in the RRCR learning condition. Experiment 2 findings revealed that mismatching picture-word pairings elicited a robust N400 event-related brain potential only for words that were taught in the RRCR condition. In addition, children were more accurate in identifying picture-word matches and mismatches for words taught in the RRCR condition, relative to the immediate retrieval condition. Conclusions Retrieval practice that requires contextual reinstatement through spacing results in enhanced word learning and long-term retention of words. Both typically developing children and children with developmental language disorder benefit from this type of retrieval procedure. Supplemental Material https://doi.org/10.23641/asha.7927112.
Project description:The Stroop task is an excellent tool to test whether reading a word automatically activates its associated meaning, and it has been widely used in mono- and bilingual contexts. Despite of its ubiquity, the task has not yet been employed to test the automaticity of recently established word-concept links in novel-word-learning studies, under strict experimental control of learning and testing conditions. In three experiments, we thus paired novel words with native language (German) color words via lexical association and subsequently tested these words in a manual version of the Stroop task. Two crucial findings emerged: When novel word Stroop trials appeared intermixed among native-word trials, the novel-word Stroop effect was observed immediately after the learning phase. If no native color words were present in a Stroop block, the novel-word Stroop effect only emerged 24 h later. These results suggest that the automatic availability of a novel word's meaning depends either on supportive context from the learning episode and/or on sufficient time for memory consolidation. We discuss how these results can be reconciled with the complementary learning systems account of word learning.
Project description:A fundamental component of language acquisition involves organizing words into grammatical categories. Previous literature has suggested a number of ways in which this categorization task might be accomplished. Here we ask whether the patterning of the words in a corpus of linguistic input (distributional information) is sufficient, along with a small set of learning biases, to extract these underlying structural categories. In a series of experiments, we show that learners can acquire linguistic form-classes, generalizing from instances of the distributional contexts of individual words in the exposure set to the full range of contexts for all the words in the set. Crucially, we explore how several specific distributional variables enable learners to form a category of lexical items and generalize to novel words, yet also allow for exceptions that maintain lexical specificity. We suggest that learners are sensitive to the contexts of individual words, the overlaps among contexts across words, the non-overlap of contexts (or systematic gaps in information), and the size of the exposure set. We also ask how learners determine the category membership of a new word for which there is very sparse contextual information. We find that, when there are strong category cues and robust category learning of other words, adults readily generalize the distributional properties of the learned category to a new word that shares just one context with the other category members. However, as the distributional cues regarding the category become sparser and contain more consistent gaps, learners show more conservatism in generalizing distributional properties to the novel word. Taken together, these results show that learners are highly systematic in their use of the distributional properties of the input corpus, using them in a principled way to determine when to generalize and when to preserve lexical specificity.
Project description:Purpose The goal was to determine whether interactive book reading outcomes for children with developmental language disorder (DLD) were affected by manipulation of dose (i.e., the number of exposures to the target word during a book reading session) and dose frequency (i.e., the number of repeated book reading sessions) and whether pretreatment factors predicted treatment response variation. Method Thirty-four kindergarten children with DLD (aged 5;0-6;2 [years;months]) were taught 1 set of words using the Dose 6 and Dose Frequency 6 format from a prior study (Storkel, Voelmle, et al., 2017) and taught a different set of words using an alternative format, either Dose 4 × Dose Frequency 9 or Dose 9 × Dose Frequency 4, determined through random assignment. Word learning was tracked for each treatment via a definition task prior to, during, and after treatment. Results Results showed that children with DLD learned a significant number of words during treatment regardless of the dose and dose frequency format but that significant forgetting of newly learned words occurred in all formats once treatment was withdrawn. Individual differences in word learning were related to Clinical Evaluation of Language Fundamentals Core Language and Understanding Spoken Paragraphs scores. Conclusion When administered at an adequate intensity, variation in the dose and dose frequency of interactive book reading does not appear to influence word learning by children with DLD. Although interactive book reading continues to show promise as an effective word learning intervention for children with DLD, further development is needed to enhance the effectiveness of this treatment approach. Supplemental Material https://doi.org/10.23641/asha.9745181.
Project description:Word learning depends not only on efficient online binding of phonological, orthographic and lexical information, but also on consolidation of new word representations into permanent lexical memory. Work on word learning under a variety of contexts indicates that reading and language skill impact facility of word learning in both print and speech. In addition, recent research finds that individuals with language impairments show deficits in both initial word form learning and in maintaining newly learned representations over time, implicating mechanisms associated with maintenance that may be driven by deficits in overnight consolidation. Although several recent studies have explored the neural bases of overnight consolidation of newly learned words, no extant work has examined individual differences in overnight consolidation at the neural level. The current study addresses this gap in the literature by investigating how individual differences in reading and language skills modulate patterns of neural activation associated with newly learned words following a period of overnight consolidation. Specifically, a community sample of adolescents and young adults with significant variability in reading and oral language (vocabulary) ability were trained on two spoken artificial lexicons, one in the evening on the day before fMRI scanning and one in the morning just prior to scanning. Comparisons of activation between words that were trained and consolidated vs. those that were trained but not consolidated revealed increased cortical activation in a number of language associated and memory associated regions. In addition, individual differences in age, reading skill and vocabulary modulated learning rate in our artificial lexicon learning task and the size of the cortical consolidation effect in the precuneus/posterior cingulate, such that older readers and more skilled readers had larger cortical consolidation effects in this learning-critical region. These findings suggest that age (even into late adolescence) and reading and language skills are important individual differences that affect overnight consolidation of newly learned words. These findings have significant implications for understanding reading and language disorders and should inform pedagogical models.