Labels and object categorization in six- and nine-month-olds: tracking labels across varying carrier phrases

Language shapes object categorization in infants. This starts as a general enhanced attentional effect of language, which narrows to a specific link between labels and categories by twelve months. The current experiments examined this narrowing effect by investigating when infants track a consistent label across varied input. Six-month-old infants (N = 48) were familiarized to category exemplars, each presented with the exact same labeling phrase or the same label in different phrases. Evidence of object categorization at test was only found with the same phrase, suggesting that infants were not tracking the label’s consistency, but rather that of the entire input. Nine-month-olds (N = 24) did show evidence of categorization across the varied phrases, suggesting that they were tracking the consistent label across the varied input.     

The animate–inanimate distinction in preschool children

This study examined the development of the animate–inanimate (A–I) distinction in relation to other taxonomic categories in early childhood. Four‐ and 5‐year‐old children were administered two tasks measuring knowledge of taxonomic categories at various levels of inclusiveness. Across both matching‐to‐sample and object sorting tasks, the same pattern of categorization development was observed. Mastery of basic‐ and superordinate‐level categories was demonstrated by 4 years of age. Although 5‐year‐old children performed above chance on A–I level categories, their abilities were not as mature as those of adults. Results of this study support and extend previous studies investigating the development of children's understanding of naïve biology during the preschool years.     

Visual variability affects early verb learning

Research demonstrates that within‐category visual variability facilitates noun learning; however, the effect of visual variability on verb learning is unknown. We habituated 24‐month‐old children to a novel verb paired with an animated star‐shaped actor. Across multiple trials, children saw either a single action from an action category (identical actions condition, for example, travelling while repeatedly changing into a circle shape) or multiple actions from that action category (variable actions condition, for example, travelling while changing into a circle shape, then a square shape, then a triangle shape). Four test trials followed habituation. One paired the habituated verb with a new action from the habituated category (e.g., ‘dacking’ + pentagon shape) and one with a completely novel action (e.g., ‘dacking’ + leg movement). The others paired a new verb with a new same‐category action (e.g., ‘keefing’ + pentagon shape), or a completely novel category action (e.g., ‘keefing’ + leg movement). Although all children discriminated novel verb/action pairs, children in the identical actions condition discriminated trials that included the completely novel verb, while children in the variable actions condition discriminated the out‐of‐category action. These data suggest that – as in noun learning – visual variability affects verb learning and children's ability to form action categories.     

Crossed categorization outside the lab: Findings from a factorial survey experiment

Crossed categorization studies investigate intergroup attitudes in situations when two categorization dimensions are simultaneously salient, often looking at artificial groups in laboratory settings. The current study tests (a) patterns of evaluation in crossed categorization scenarios when more than two real-life categorization dimensions are crossed, and (b) the moderating role of identity importance. We conduct a factorial survey experiment with a diverse sample (N = 524), crossing eight categorization dimensions. The results provide strong support for the additive pattern of crossed categorization, challenging the view that with an increased number of categories category-based information processing will not be used. Identity importance predicts the strength of intergroup bias only on the dimension of religion, which was the dominant dimension in this sample. The study contributes to multiple and crossed categorization literature by testing some of its key assumptions using a design that increases the ecological validity of the findings.     

Utilizing driving simulators for persons with multiple sclerosis: A scoping review

ObjectiveThis scoping review synopsized and mapped the evidence on the utility of driving simulators for drivers with Multiple Sclerosis (MS) including participant characteristics (e.g., demographic, clinical) suited to simulator use; and driving scenario environments, maneuvers, and outcomes reflective of driving performance.Data SourcesThe research team searched six databases for English studies on driving simulator performance in drivers with MS.Study SelectionFour reviewers independently screened 976 unique titles, 148 abstracts, and 18 full-text sources for study inclusion or exclusion. Inclusion criteria ensured that studies utilized measures of driving simulator performance in adults 18 years or older with MS.Data ExtractionReviewers independently charted, verified, and achieved consensus on 100% of the data in the extraction table.Data SynthesisThe scoping review included thirteen studies (twelve assessment, one intervention), published between 2001 and 2021. Studies included small samples (N = 11–50) of adults (M age = 36–50 years; 40–91% female), mostly with a relapsing-remitting (53–100%) diagnosis and low to moderate physical disability (Expanded Disability Status Scale score < 6.0). The assessment studies utilized driving scenarios to assess pre-driving (n = 1) or driving abilities (n = 2), responses to hazardous events in suburban (n = 1) or urban environments (n = 4), or the ability to maintain speed or lateral lane positioning during monotonous highway drives (n = 7), with four scenarios also including responses to secondary divided attention tasks. The intervention study utilized driving simulation as a training program to improve driving-related skills.ConclusionsThe evidence on the utility of driving simulators for adults with MS is limited to assessment of driving performance, mostly during monotonous highway drives. Further research should consider exploring how driving simulators can be utilized to assess driving performance in other environments or for intervention. Gender should be examined to support gender diverse populations.     

Analysis of Interactions and Nonlinear Effects with Missing Data: A Factored Regression Modeling Approach Using Maximum Likelihood Estimation

Abstract

When estimating multiple regression models with incomplete predictor variables, it is necessary to specify a joint distribution for the predictor variables. A convenient assumption is that this distribution is a multivariate normal distribution, which is also the default in many statistical software packages. This distribution will in general be misspecified if predictors with missing data have nonlinear effects (e.g., x²) or are included in interaction terms (e.g., x·z). In the present article, we introduce a factored regression modeling approach for estimating regression models with missing data that is based on maximum likelihood estimation. In this approach, the model likelihood is factorized into a part that is due to the model of interest and a part that is due to the model for the incomplete predictors. In three simulation studies, we showed that the factored regression modeling approach produced valid estimates of interaction and nonlinear effects in regression models with missing values on categorical or continuous predictor variables under a broad range of conditions. We developed the R package mdmb, which facilitates a user-friendly application of the factored regression modeling approach, and present a real-data example that illustrates the flexibility of the software.     

No intrinsic number bias: Evaluating the role of perceptual discriminability in magnitude categorization

Accumulating evidence suggests that there is a spontaneous preference for numerical, compared to non-numerical (e.g., cumulative surface area), information. However, given a paucity of research on the perception of non-numerical magnitudes, it is unclear whether this preference reflects a specific bias towards number, or a general bias towards the more perceptually discriminable dimension (i.e., number). Here, we found that when the number and area of visual dot displays were matched in mathematical ratio, number was more perceptually discriminable than area in both adults and children. Moreover, both adults and children preferentially categorized these ratio-matched stimuli based on number, consistent with previous work. However, when number and area were matched in perceptual discriminability, a different pattern of results emerged. In particular, children preferentially categorized stimuli based on area, suggesting that children's previously observed number bias may be due to a mismatch in the perceptual discriminability of number and area, not an intrinsic salience of number. Interestingly, adults continued to categorize the displays on the basis of number. Altogether, these findings suggest a dominant role for area during childhood, refuting the claim that number is inherently and uniquely salient. Yet they also reveal an increased salience of number that emerges over development. Potential explanations for this developmental shift are discussed.

Research Highlights

• Previous work found that children and adults spontaneously categorized dot array stimuli by number, over other magnitudes (e.g., area), suggesting number is uniquely salient.
• However, here we found that when number and area were matched by ratio, as in prior work, number was significantly more perceptually discriminable than area.
• When number and area were made equally discriminable (‘perceptually-matched’), children, contra adults, spontaneously categorized stimuli by area over number (and other non-numerical magnitudes).
• These findings suggest that area may be uniquely salient early in childhood, with the previously-observed number bias not emerging until later in development.