Understanding of the functions of forgiveness among preschoolers.

Forgiveness plays an important role in restoring and maintaining cooperative relationships. Previous studies have demonstrated that young children could forgive transgressors both as a third party and as a victim. However, the research on young children's understanding of forgiveness is scant. This study focused on the two main functions of forgiveness-the restoration of a damaged relationship between the victim and the transgressor and the positive emotional change in the victim toward the transgressor. In this study, 48 4-year-olds (25 girls), 50 5-year-olds (21 girls), and 50 6-year-olds (21 girls) in Japan heard stories in which a victim either did or did not forgive a transgressor. They answered questions about the relationship between the victim and the transgressor and the victim's feelings toward the transgressor. Regarding the restoration of a damaged relationship, 4- to 6-year-olds understood that the restoration could occur in the presence of forgiveness. Yet, 6-year-olds showed more distinctive belief than 4- and 5-year-olds that the damaged relationship remains unrestored without forgiveness from the victim. For emotional changes, 6-year-olds understood that the forgiving victim would experience positive emotional changes, whereas the unforgiving victim would not. However, 4- and 5-year-olds expected positive emotional changes even without forgiveness, although they anticipated greater changes after forgiveness. The results show that the understanding of the important functions of forgiveness is present at 4 years of age and matures by 6 years of age. Children may develop a sophisticated understanding of the functions of forgiveness later than the actual forgiving behavior.

Exploration of factors affecting webcam-based automated gaze coding.

Online experiments have been transforming the field of behavioral research, enabling researchers to increase sample sizes, access diverse populations, lower the costs of data collection, and promote reproducibility. The field of developmental psychology increasingly exploits such online testing approaches. Since infants cannot give explicit behavioral responses, one key outcome measure is infants' gaze behavior. In the absence of automated eyetrackers in participants' homes, automatic gaze classification from webcam data would make it possible to avoid painstaking manual coding. However, the lack of a controlled experimental environment may lead to various noise factors impeding automatic face detection or gaze classification. We created an adult webcam dataset that systematically reproduced noise factors from infant webcam studies which might affect automated gaze coding accuracy. We varied participants' left-right offset, distance to the camera, facial rotation, and the direction of the lighting source. Running two state-of-the-art classification algorithms (iCatcher+ and OWLET) revealed that facial detection performance was particularly affected by the lighting source, while gaze coding accuracy was consistently affected by the distance to the camera and lighting source. Morphing participants' faces to be unidentifiable did not generally affect the results, suggesting facial anonymization could be used when making online video data publicly available, for purposes of further study and transparency. Our findings will guide improving study design for infant and adult participants during online experiments. Moreover, training algorithms using our dataset will allow researchers to improve robustness and allow developmental psychologists to leverage online testing more efficiently.

Large-scale data decipher children's scale errors: A meta-analytic approach using the zero-inflated Poisson models.

Scale errors are intriguing phenomena in which a child tries to perform an object-specific action on a tiny object. Several viewpoints explaining the developmental mechanisms underlying scale errors exist; however, there is no unified account of how different factors interact and affect scale errors, and the statistical approaches used in the previous research do not adequately capture the structure of the data. By conducting a secondary analysis of aggregated datasets across nine different studies (n = 528) and using more appropriate statistical methods, this study provides a more accurate description of the development of scale errors. We implemented the zero-inflated Poisson (ZIP) regression that could directly handle the count data with a stack of zero observations and regarded developmental indices as continuous variables. The results suggested that the developmental trend of scale errors was well documented by an inverted U-shaped curve rather than a simple linear function, although nonlinearity captured different aspects of the scale errors between the laboratory and classroom data. We also found that repeated experiences with scale error tasks reduced the number of scale errors, whereas girls made more scale errors than boys. Furthermore, a model comparison approach revealed that predicate vocabulary size (e.g., adjectives or verbs), predicted developmental changes in scale errors better than noun vocabulary size, particularly in terms of the presence or absence of scale errors. The application of the ZIP model enables researchers to discern how different factors affect scale error production, thereby providing new insights into demystifying the mechanisms underlying these phenomena. A video abstract of this article can be viewed at https://youtu.be/1v1U6CjDZ1Q RESEARCH HIGHLIGHTS: We fit a large dataset by aggregating the existing scale error data to the zero-inflated Poisson (ZIP) model. Scale errors peaked along the different developmental indices, but the underlying statistical structure differed between the in-lab and classroom datasets. Repeated experiences with scale error tasks and the children's gender affected the number of scale errors produced per session. Predicate vocabulary size (e.g., adjectives or verbs) better predicts developmental changes in scale errors than noun vocabulary size.

Development and Verification of Postural Control Assessment Using Deep-Learning-Based Pose Estimators: Towards Clinical Applications.

Occupational therapists evaluate various aspects of a client's occupational performance. Among these, postural control is one of the fundamental skills that need assessment. Recently, several methods have been proposed to estimate postural control abilities using deep-learning-based approaches. Such techniques allow for the potential to provide automated, precise, fine-grained quantitative indices simply by evaluating videos of a client engaging in a postural control task. However, the clinical applicability of these assessment tools requires further investigation. In the current study, we compared three deep-learning-based pose estimators to assess their clinical applicability in terms of accuracy of pose estimations and processing speed. In addition, we verified which of the proposed quantitative indices for postural controls best reflected the clinical evaluations of occupational therapists. A framework using deep-learning techniques broadens the possibility of quantifying clients' postural control in a more fine-grained way compared with conventional coarse indices, which can lead to improved occupational therapy practice.

Mask wearing in Japanese and French nursery schools: The perceived impact of masks on communication.

Due to the global COVID-19 pandemic, covering the mouth region with a face mask became pervasive in many regions of the world, potentially impacting how people communicate with and around children. To explore the characteristics of this masked communication, we asked nursery school educators, who have been at the forefront of daily masked interaction with children, about their perception of daily communicative interactions while wearing a mask in an online survey. We collected data from French and Japanese nursery school educators to gain an understanding of commonalities and differences in communicative behavior with face masks given documented cultural differences in pre-pandemic mask wearing habits, face scanning patterns, and communicative behavior. Participants (177 French and 138 Japanese educators) reported a perceived change in their own communicative behavior while wearing a mask, with decreases in language quantity and increases in language quality and non-verbal cues. Comparable changes in their team members' and children's communicative behaviors were also reported. Moreover, our results suggest that these changes in educators' communicative behaviors are linked to their attitudes toward mask wearing and their potential difficulty in communicating following its use. These findings shed light on the impact of pandemic-induced mask wearing on children's daily communicative environment.

Object labeling activates young children's scale errors at an early stage of verb vocabulary growth.

Scale errors are intriguing developmental phenomena in which young children attempt to perform impossible object-specific actions toward miniature-sized objects. Of several related cognitive abilities, lexical development during toddlerhood enhances scale error production by making objects' semantic representations dominant over perceptual information. To directly address the effect of activated semantic representations on scale errors, we examined whether and when object labeling affected scale errors. Toddlers aged 18 to 30 months (N = 72) performed a body-based scale error task twice: in one session with specific object labels provided (e.g., "chair") and in the other session with general pronouns provided (e.g., "this"). Using different developmental indices, including chronological age and productive vocabulary size of nouns, verbs, and adjectives, the enhancement effect of object labeling was detected only for children whose verb vocabulary size was classified into the medium group (3-26 words). Moreover, verb vocabulary size was determined to be the best predictor of scale error production among the candidate developmental indices. We also found that toddlers produced more scale errors in the first session that they performed the task compared with the second session. In addition to revealing that careful control of relevant factors (e.g., developmental indices, labeling, task repetition) is required for scale error research, this study sheds light on the relevance of verb vocabulary on scale errors.

When "shoe" becomes free from "putting on": The link between early meanings of object words and object-specific actions.

Nouns referring to objects dominate children's early vocabulary over verbs referring to actions. However, some scholars have argued that early object-word meanings cannot be easily classified into specific object categories; rather, they have much undifferentiated meanings in which both objects and their specific actions are intertwined. We experimentally investigated this view using a two-alternative forced-choice task involving toddlers aged 18-23 months (n = 69). Both the cross-sectional and longitudinal results suggested that unlike older toddlers, younger ones could not select the correct referents when objects and object-specific actions were presented separately (e.g., "doing a filler action with shoes" vs. "putting on filler objects as if they were shoes") despite being successful when both were matched (e.g., "putting shoes on" vs. "doing a filler action with filler objects"). Additionally, toddlers failed to judge object-word referents solely by object-specific actions. These results indicated that early object-word meanings constitute the undifferentiated fusion of both objects and actions, and they subsequently differentiate into specific object categories independent of actions. Furthermore, the extent of such semantic differentiation is associated with the vocabulary growth of action words, suggesting that object-word meaning differentiation encouraged toddlers to develop new labels that could distinguish specific actions from objects. These findings revealed the uniqueness of young children's object-word comprehension, which is different from that of adults.

COVID-19 school and kindergarten closure relates to children's social relationships: a longitudinal study in Japan.

The COVID-19 pandemic has led children to experience school closures. Although increasing evidence suggests that such intense social quarantine influences children's social relationships with others, longitudinal studies are limited. Using longitudinal data collected during (T1) and after (T2) intensive school closure and home confinement, this study investigated the impacts of social quarantine on children's social relationships. Japanese parents of children aged 0-9 years (n = 425) completed an online questionnaire that examined children's socio-emotional behavior and perceived proximity to parents or others. The results demonstrated that social quarantine was not significantly related to children's socio-emotional behavior across all age groups. However, changes in children's perceived proximity varied depending on certain age-related factors: elementary schoolers' perceived closeness to parents significantly decreased after the reopening of schools, whereas that to others, such as peers, increased. Such effects were not observed in infants and preschoolers. The follow-up survey 9-month after the reopening of schools (T3; n = 130) did not detect significant differences in both children's socio-emotional behavior and perceived proximity from that after the intense quarantine. These findings suggest that school closure and home confinement may have influenced children's social development differently across their age, and its effects were larger in perceived closeness rather than social behavior.

Looking represents choosing in toddlers: Exploring the equivalence between multimodal measures in forced-choice tasks.

In the two-alternative forced-choice (2AFC) paradigm, manual responses such as pointing have been widely used as measures to estimate cognitive abilities. While pointing measurements can be easily collected, coded, analyzed, and interpreted, absent responses are often observed particularly when adopting these measures for toddler studies, which leads to an increase of missing data. Although looking responses such as preferential looking can be available as alternative measures in such cases, it is unknown how well looking measurements can be interpreted as equivalent to manual ones. This study aimed to answer this question by investigating how accurately pointing responses (i.e., left or right) could be predicted from concurrent preferential looking. Using pre-existing videos of toddlers aged 18-23 months engaged in an intermodal word comprehension task, we developed models predicting manual from looking responses. Results showed substantial prediction accuracy for both the Simple Majority Vote and Machine Learning-Based classifiers, which indicates that looking responses would be reasonable alternative measures of manual ones. However, the further exploratory analysis revealed that when applying the created models for data of toddlers who did not produce clear pointing responses, the estimation agreement of missing pointing between the models and the human coders slightly dropped. This indicates that looking responses without pointing were qualitatively different from those with pointing. Bridging two measurements in forced-choice tasks would help researchers avoid wasting collected data due to the absence of manual responses and interpret results from different modalities comprehensively.

Computer Vision-Based Approach for Quantifying Occupational Therapists' Qualitative Evaluations of Postural Control.

This study aimed to leverage computer vision (CV) technology to develop a technique for quantifying postural control. A conventional quantitative index, occupational therapists' qualitative clinical evaluations, and CV-based quantitative indices using an image analysis algorithm were applied to evaluate the postural control of 34 typically developed preschoolers. The effectiveness of the CV-based indices was investigated relative to current methods to explore the clinical applicability of the proposed method. The capacity of the CV-based indices to reflect therapists' qualitative evaluations was confirmed. Furthermore, compared to the conventional quantitative index, the CV-based indices provided more detailed quantitative information with lower costs. CV-based evaluations enable therapists to quantify details of motor performance that are currently observed qualitatively. The development of such precise quantification methods will improve the science and practice of occupational therapy and allow therapists to perform to their full potential.

Initial noun meanings do not differentiate into object categories: An experimental approach to Werner and Kaplan's hypothesis.

During the initial stage of language development, nouns corresponding to "object categories" are known to be acquired earlier than other parts of speech, including verbs. However, it is unclear whether the semantic content of words is the same for toddlers who have just begun to learn them and adult speakers. This preliminary study experimentally investigated the theoretical hypothesis of Werner and Kaplan, which posited that the initial meanings of noun-like words do not differentiate into specific categories of objects themselves but rather refer to holistic event categories. Toddlers aged 19-35 months (N = 36) were prompted to select one of two juxtaposed video stimuli (e.g., "putting shoes on" vs. "rubbing two baskets" in the match condition, "putting baskets on" vs. "rubbing shoes" in the mismatch condition) using questions about noun-like words (e.g., "Which is shoes?"). Statistical modeling demonstrated that the meanings of noun-like words for toddlers under 21 months of age or with a vocabulary size of less than 140 words were deeply influenced by conventional actions related to the objects (e.g., "putting shoes on"), whereas they subsequently differentiated into specific object categories (e.g., "shoes" alone), becoming "true nouns." These findings support Werner and Kaplan's hypothesis and provide the first experimental evidence for the theoretical and observational assumptions that early words are not easily classified into parts of speech only by their vocables (e.g., nouns, verbs). We discuss the flexibility of vocable-meaning connections during early language development by proposing the "semantic pluripotency hypothesis."

Conventionality and Intentionality as Potential Contributors to Ideational Praxis in Japanese Preschoolers: An Exploratory Study with Correspondence Analysis.

Ideation is an essential central concept in sensory integration theory. The Test of Ideational Praxis (TIP) (May-Benson, ) is the first instrument developed to specifically assess children's ideational abilities but qualitative differences of its performance are not well examined. The purpose of the present study was to explore the components of ideational abilities that influenced the TIP score or its developmental change. The TIP was administered to 119 Japanese preschoolers, aged 3-6 years. The demonstrated actions were categorized based on the scoring criteria, and scores were calculated by summing the number of actions. Correspondence analysis was conducted to summarize the data into several components. Results indicate that conventionality and intentionality are contributors to ideational abilities in preschoolers. Conventionality was significantly related to the development of ideation, while intentionality was significantly associated with the TIP score. These results suggest that action differences during the TIP, in addition to the score, may be helpful for interpreting the results of the TIP when it is used clinically. Although the data does not sufficiently explain these two components, the results add new evidence for understanding preschoolers' ideational praxis. Further research is needed on factors related to the TIP score and development of ideational abilities. Copyright © 2016 John Wiley & Sons, Ltd.