Testing Alternative Hypotheses Regarding the Association Between Behavioral Inhibition and Language Development in Toddlerhood

Studies have reported an inverse association between language development and behavioral inhibition or shyness across childhood, but the direction of this association remains unclear. This study tested alternative hypotheses regarding this association in a large sample of toddlers. Data on behavioral inhibition and expressive and receptive language abilities were collected from 816 twins at ages 14, 20, and 24 months. Growth and regression models were fit to the data to assess the longitudinal associations between behavioral inhibition and language development from 14 to 24 months. Overall, there were significant associations between behavioral inhibition and expressive language, and minimal associations with receptive language, indicating that the association is better explained by reticence to respond rather than deficient language development.     

Using Focus Groups to Examine the Consequential Aspect of validity

How can focus groups be used to examine issues of consequential validity in large-scale assessment? In relation to a new large-scale assessment, what are teacher concerns, and how do these concerns differ by type of school district? What are the strengths and weaknesses in this approach to looking at consequential validity?     

Contraction and extension of Vorticella and its mechanical characterization under flow loading

We have studied the contraction and extension of Vorticella convallaria and its mechanical properties with a microfluidic loading system. Cells of V. convallaria were injected to a microfluidic channel (500 μm in width and 100 μm in height) and loaded by flow up to ∼350 mm s⁻¹. The flow produced a drag force on the order of nanonewton on a typical vorticellid cell body. We gradually increased the loading force on the same V. convallaria specimen and examined its mechanical property and stalk motion of V. convallaria. With greater drag forces, the contraction distance linearly decreased; the contracted length was close to around 90% of the stretched length. We estimated the drag force on Vorticella in the channel by calculating the force on a sphere in a linear shear flow.     

Utility of Feedback Has a Greater Impact on Learning than Ease of Decoding

While feedback is a key facilitator of learning, researchers have yet to determine the ideal feedback process for optimal performance in learners. The current study investigates the combined effects of ease of decoding, and utility of feedback during learning. Accuracy and rate of learning were recorded alongside changes to the feedback related negativity (FRN), an event‐related potential (ERP) elicited by feedback stimuli. This study investigates the FRN within the context of future‐focused directive feedback (DF), in addition to past‐focused evaluative feedback (EF) typically seen in the neuroscience literature. Results indicate a main effect of utility together with an interaction with ease of decoding on the accuracy data, but only the main effect of utility on learning rate. DF produced an FRN, like EF, which was then larger during high‐utility feedback, specifically following negative EF or when hard‐to‐decode. Implications and future research directions are discussed.