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.

Beyond the Shape of Things: Infants Can Be Taught to Generalize Nouns by Objects' Functions.

Two-year-olds typically extend labels of novel objects by the objects' shape (shape bias), whereas adults do so by the objects' function. Is this because shape is conceptually easier to comprehend than function? To test whether the conceptual complexity of function prevents infants from developing a function bias, we trained twelve 17-month-olds (function-training group) to focus on objects' functions when labeling the objects over a period of 7 weeks. Our training was similar to previously used methods in which 17-month-olds were successfully taught to focus on the shape of objects, resulting in a precocious shape bias. We exposed another 12 infants (control group) to the same objects over 7 weeks but without labeling the items or demonstrating their functions. Only the infants in the function-training group developed a function bias. Thus, the conceptual complexity of function was not a barrier for developing a function bias, which suggests that the shape bias emerges naturally because shape is perceptually more accessible than function.

Seeing Iconic Gesture Promotes First- and Second-Order Verb Generalization in Preschoolers.

This study investigated whether seeing iconic gestures depicting verb referents promotes two types of generalization. We taught 3- to 4-year-olds novel locomotion verbs. Children who saw iconic manner gestures during training generalized more verbs to novel events (first-order generalization) than children who saw interactive gestures (Experiment 1, N = 48; Experiment 2, N = 48) and path-tracing gestures (Experiment 3, N = 48). Furthermore, immediately (Experiments 1 and 3) and after 1 week (Experiment 2), the iconic manner gesture group outperformed the control groups in subsequent generalization trials with different novel verbs (second-order generalization), although all groups saw interactive gestures. Thus, seeing iconic gestures that depict verb referents helps children (a) generalize individual verb meanings to novel events and (b) learn more verbs from the same subcategory.

Seeing Iconic Gestures While Encoding Events Facilitates Children's Memory of These Events.

An experiment with 72 three-year-olds investigated whether encoding events while seeing iconic gestures boosts children's memory representation of these events. The events, shown in videos of actors moving in an unusual manner, were presented with either iconic gestures depicting how the actors performed these actions, interactive gestures, or no gesture. In a recognition memory task, children in the iconic gesture condition remembered actors and actions better than children in the control conditions. Iconic gestures were categorized based on how much of the actors was represented by the hands (feet, legs, or body). Only iconic hand-as-body gestures boosted actor memory. Thus, seeing iconic gestures while encoding events facilitates children's memory of those aspects of events that are schematically highlighted by gesture.

GestuRe and ACtion Exemplar (GRACE) video database: stimuli for research on manners of human locomotion and iconic gestures.

Human locomotion is a fundamental class of events, and manners of locomotion (e.g., how the limbs are used to achieve a change of location) are commonly encoded in language and gesture. To our knowledge, there is no openly accessible database containing normed human locomotion stimuli. Therefore, we introduce the GestuRe and ACtion Exemplar (GRACE) video database, which contains 676 videos of actors performing novel manners of human locomotion (i.e., moving from one location to another in an unusual manner) and videos of a female actor producing iconic gestures that represent these actions. The usefulness of the database was demonstrated across four norming experiments. First, our database contains clear matches and mismatches between iconic gesture videos and action videos. Second, the male actors and female actors whose action videos matched the gestures in the best possible way, perform the same actions in very similar manners and different actions in highly distinct manners. Third, all the actions in the database are distinct from each other. Fourth, adult native English speakers were unable to describe the 26 different actions concisely, indicating that the actions are unusual. This normed stimuli set is useful for experimental psychologists working in the language, gesture, visual perception, categorization, memory, and other related domains.

"Prior experience with unlabeled actions promotes 3-year-old children's verb learning": Correction.

Reports an error in "Prior experience with unlabeled actions promotes 3-year-old children's verb learning" by Suzanne Aussems, Katherine H. Mumford and Sotaro Kita (Journal of Experimental Psychology: General, Advanced Online Publication, Jul 15, 2021, np). In the original article, acknowledgment of and formatting for Economic and Social Research Council funding was omitted. The author note and copyright line now reflect the standard acknowledgment of and formatting for the funding received for this article. All versions of this article have been corrected. (The following abstract of the original article appeared in record 2021-63321-001). This study investigated what type of prior experience with unlabeled actions promotes 3-year-old children's verb learning. We designed a novel verb learning task in which we manipulated prior experience with unlabeled actions and the gesture type children saw with this prior experience. Experiment 1 showed that children (N = 96) successfully generalized more novel verbs when they had prior experience with unlabeled exemplars of the referent actions ("relevant exemplars"), but only if the referent actions were highlighted with iconic gestures during prior experience. Experiment 2 showed that children (N = 48) successfully generalized more novel verbs when they had prior experience with one relevant exemplar and an iconic gesture than with two relevant exemplars (i.e., the same referent action performed by different actors) shown simultaneously. However, children also successfully generalized verbs above chance in the two-relevant-exemplars condition (without the help of iconic gesture). Overall, these findings suggest that prior experience with unlabeled actions is an important first step in children's verb learning process, provided that children get a cue for focusing on the relevant information (i.e., actions) during prior experience so that they can create stable memory representations of the actions. Such stable action memory representations promote verb learning because they make the actions stand out when children later encounter labeled exemplars of the same actions. Adults can provide top-down cues (e.g., iconic gestures) and bottom-up cues (e.g., simultaneous exemplars) to focus children's attention on actions; however, iconic gesture is more beneficial for successful verb learning than simultaneous exemplars. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Prior experience with unlabeled actions promotes 3-year-old children's verb learning.

[Correction Notice: An Erratum for this article was reported online in Journal of Experimental Psychology: General on Jan 6 2022 (see record 2022-20753-001). In the original article, acknowledgment of and formatting for Economic and Social Research Council funding was omitted. The author note and copyright line now reflect the standard acknowledgment of and formatting for the funding received for this article. All versions of this article have been corrected.] This study investigated what type of prior experience with unlabeled actions promotes 3-year-old children's verb learning. We designed a novel verb learning task in which we manipulated prior experience with unlabeled actions and the gesture type children saw with this prior experience. Experiment 1 showed that children (N = 96) successfully generalized more novel verbs when they had prior experience with unlabeled exemplars of the referent actions ("relevant exemplars"), but only if the referent actions were highlighted with iconic gestures during prior experience. Experiment 2 showed that children (N = 48) successfully generalized more novel verbs when they had prior experience with one relevant exemplar and an iconic gesture than with two relevant exemplars (i.e., the same referent action performed by different actors) shown simultaneously. However, children also successfully generalized verbs above chance in the two-relevant-exemplars condition (without the help of iconic gesture). Overall, these findings suggest that prior experience with unlabeled actions is an important first step in children's verb learning process, provided that children get a cue for focusing on the relevant information (i.e., actions) during prior experience so that they can create stable memory representations of the actions. Such stable action memory representations promote verb learning because they make the actions stand out when children later encounter labeled exemplars of the same actions. Adults can provide top-down cues (e.g., iconic gestures) and bottom-up cues (e.g., simultaneous exemplars) to focus children's attention on actions; however, iconic gesture is more beneficial for successful verb learning than simultaneous exemplars. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Young children's screen time during the first COVID-19 lockdown in 12 countries.

Older children with online schooling requirements, unsurprisingly, were reported to have increased screen time during the first COVID-19 lockdown in many countries. Here, we ask whether younger children with no similar online schooling requirements also had increased screen time during lockdown. We examined children's screen time during the first COVID-19 lockdown in a large cohort (n = 2209) of 8-to-36-month-olds sampled from 15 labs across 12 countries. Caregivers reported that toddlers with no online schooling requirements were exposed to more screen time during lockdown than before lockdown. While this was exacerbated for countries with longer lockdowns, there was no evidence that the increase in screen time during lockdown was associated with socio-demographic variables, such as child age and socio-economic status (SES). However, screen time during lockdown was negatively associated with SES and positively associated with child age, caregiver screen time, and attitudes towards children's screen time. The results highlight the impact of the COVID-19 lockdown on young children's screen time.