Exploring the effect of testing on forgetting in vocabulary learning: an examination of the bifurcation model

ABSTRACT

Research on the testing effect demonstrated a stronger decrease in performance for repeated studying compared to repeated testing. The bifurcation model attributes this test-delay interaction to different distributions of item memory strength. The present study tested the assumptions of the bifurcation model for learning foreign language vocabulary. We hypothesised an elimination or reduction of the interaction in a test/feedback condition because feedback prevents the bifurcation of item memory strength. Our experiment based on a 3 (Learning Method within: Test, test/feedback, copy)?×?3 (Retention Interval between: Immediate, 1-week, 2-weeks) mixed factorial design with a sample of N = 122. The greatest long-term retention was achieved in the test/feedback condition. The bifurcation model was supported by a reduced test-delay interaction for the test/feedback condition. Further evidence for the bifurcation model is needed as interpretations on the dropout rates of items with different recall success were limited due to a floor effect.     

Expressive suppression and financial risk taking: A mediated moderation model

This research aimed to investigate the relationship between the habitual use of expressive suppression, a type of emotion regulation strategy, and risk taking in the financial domain. It also attempted to further examine gender as a possible moderator of this relationship and to explore the anticipated emotion related to negative potential outcomes as the mechanism behind this moderated effect. Two studies were conducted for these purposes. In Study 1, a total of 657 college students completed a test battery, including both the Emotion Regulation Questionnaire and the Grable and Lytton Risk Tolerance Scale. The results showed that expressive suppression was negatively related to financial risk taking, and gender moderated this relationship. In Study 2, 441 college students took a test battery including both the Emotion Regulation Questionnaire and a financial investment allocation task. The results replicated the findings in Study 1 and indicated that the anticipated emotion related to negative potential outcomes fully mediated the moderated effect of gender in the suppression-financial risk taking association. These findings implied the importance of considering gender differences in the prediction of financial choices from the perspective of emotion regulation.     

Encouraging pointing with the right hand,but not the left hand,gives right-handed 3-year-olds a linguistic advantage

Previous research has shown a strong positive association between right-handed gesturing and vocabulary development. However, the causal nature of this relationship remains unclear. In the current study, we tested whether gesturing with the right hand enhances linguistic processing in the left hemisphere, which is contralateral to the right hand. We manipulated the gesture hand children used in pointing tasks to test whether it would affect their performance. In either a linguistic task (verb learning) or a non-linguistic control task (memory), 131 typically developing right-handed 3-year-olds were encouraged to use either their right hand or left hand to respond. While encouraging children to use a specific hand to indicate their responses had no effect on memory performance, encouraging children to use the right hand to respond, compared to the left hand, significantly improved their verb learning performance. This study is the first to show that manipulating the hand with which children are encouraged to gesture gives them a linguistic advantage. Language lateralization in healthy right-handed children typically involves a dominant left hemisphere. Producing right-handed gestures may therefore lead to increased activation in the left hemisphere which may, in turn, facilitate forming and accessing lexical representations. It is important to note that this study manipulated gesture handedness among right-handers and does therefore not support the practice of encouraging children to become right-handed in manual activities.

Research Highlights

• Right-handed 3-year-olds were instructed to point to indicate their answers exclusively with their right or left hand in either a memory or verb learning task.
• Right-handed pointing was associated with improved verb generalization performance, but not improved memory performance.
• Thus, gesturing with the right hand, compared to the left hand, gives right-handed 3-year-olds an advantage in a linguistic but not a non-linguistic task.
• Right-handed pointing might lead to increased activation in the left hemisphere and facilitate forming and accessing lexical representations.

     

Early lexical development of children raised in institutional care in Russia

Children abandoned to institutions display a host of developmental delays, including those involving general cognition and language. The majority of published studies focus on children over 3 years of age; little is known about whether these delays may be detected earlier when children undergo rapid lexical development. To investigate the early language development of children raised in institutional settings in the Russian Federation, we compared a group of children in institutional care (n = 36; 8–35 months) to their age-matched peers raised in biological families, who have never been institutionalized (n = 72) using the Russian version of the CDI. The results suggest that institutionalization is associated with pronounced delays in children's early language development with large and robust effect sizes. Among children with a history of institutionalization, these delays are also associated with difficulties in Daily Living skills, communication, and socialization.     

Early language outcomes in Argentinean toddlers: Associations with home literacy,screen exposure and joint media engagement

This study aimed to analyse the contribution of mothers' home literacy beliefs and practices and the quantity and quality of screen media exposure on Argentinean toddler's language. In addition, we considered parent–child joint engagement, as well as adult scaffolding behaviours during the use of electronic devices. A total of 465 mothers of 18–36 months old children completed an online survey including: the MacArthur Bates CDI, home literacy, screen exposure, joint engagement and scaffolding questionnaires. We observed positive effects of literacy beliefs, PC times and verbal scaffolding on language outcomes. TV exposure contributed negatively to vocabulary and, along with educational content, to sentence use. Shared reading and screen media experiences can be an opportunity for language stimulation, provided there is dialogue and joint engagement. Passive screen exposure and inadequate content may be detrimental for toddlers' language outcomes, probably by displacement of socially significant interactions.     

Spanish-speaking caregivers’ use of referential labels with toddlers is a better predictor of later vocabulary than their use of referential gestures

Variation in how frequently caregivers engage with their children is associated with variation in children's later language outcomes. One explanation for this link is that caregivers use both verbal behaviors, such as labels, and non-verbal behaviors, such as gestures, to help children establish reference to objects or events in the world. However, few studies have directly explored whether language outcomes are more strongly associated with referential behaviors that are expressed verbally, such as labels, or non-verbally, such as gestures, or whether both are equally predictive. Here, we observed caregivers from 42 Spanish-speaking families in the US engage with their 18-month-old children during 5-min lab-based, play sessions. Children's language processing speed and vocabulary size were assessed when children were 25 months. Bayesian model comparisons assessed the extent to which the frequencies of caregivers’ referential labels, referential gestures, or labels and gestures together, were more strongly associated with children's language outcomes than a model with caregiver total words, or overall talkativeness. The best-fitting models showed that children who heard more referential labels at 18 months were faster in language processing and had larger vocabularies at 25 months. Models including gestures, or labels and gestures together, showed weaker fits to the data. Caregivers’ total words predicted children's language processing speed, but predicted vocabulary size less well. These results suggest that the frequency with which caregivers of 18-month-old children use referential labels, more so than referential gestures, is a critical feature of caregiver verbal engagement that contributes to language processing development and vocabulary growth.

Research Highlights

• We examined the frequency of referential communicative behaviors, via labels and/or gestures, produced by caregivers during a 5-min play interaction with their 18-month-old children.
• We assessed predictive relations between labels, gestures, their combination, as well as total words spoken, and children's processing speed and vocabulary growth at 25 months.
• Bayesian model comparisons showed that caregivers’ referential labels at 18 months best predicted both 25-month vocabulary measures, although total words also predicted later processing speed.
• Frequent use of referential labels by caregivers, more so than referential gestures, is a critical feature of communicative behavior that supports children's later vocabulary learning.

     

From terrible twos to sassy sixes: The development of vocabulary and executive functioning across early childhood

Across the early childhood period of development, young children exhibit considerable growth in their executive functioning (EF) and vocabulary abilities. Understanding the developmental trajectory of these seemingly interrelated processes is important as both early vocabulary and EF have been shown to predict critical academic and socio-emotional outcomes later in childhood. Although previous research suggests that EF and vocabulary are correlated in early childhood, much of the existing longitudinal research has focused on unidirectional relations among preschool child samples. The current large-scale study, therefore, sought to examine whether children's vocabulary and EF abilities are bidirectionally related over time across four measurement waves in early childhood (i.e., at ages 2, 3, 4, and 6). At each timepoint, children's vocabulary skills were positively correlated with their concurrent EF abilities. After controlling for child sex and maternal education status, the best-fitting, cross-lagged panel model was a unidirectional model whereby children's early vocabulary scores predicted their later EF performance at each timepoint. Although age 2 EF significantly predicted age 3 vocabulary size, this association was no longer significant after accounting for maternal education status. Our results illustrate that vocabulary size plays an important role in predicting children's later EF performance across various timepoints in early childhood, even after controlling for children's initial EF scores. These findings have important implications for intervention research as fostering early vocabulary acquisition may serve as a possible avenue for improving EF outcomes in young children.

Research Highlights

• Children's vocabulary size is positively correlated with their concurrent executive functioning skill at ages 2, 3, 4, and 6
• Young children's early vocabulary scores predict their later EF performance across measurement waves, even after controlling for initial EF skill
• There is stability in children's relative vocabulary size and executive functioning performance over time in early childhood