Visual short-term memory guides infants' visual attention

A new perspective on the role of physical salience in visual search: Graded effect of salience on infants' attention

We tested 6- and 8-month-old White and non-White infants (N = 53 total, 28 girls) from Northern California in a visual search task to determine whether a unique item in an otherwise homogeneous display (a singleton) attracts attention because it is a unique singleton and "pops out" in a categorical manner, or whether attention instead varies in a graded manner on the basis of quantitative differences in physical salience. Infants viewed arrays of four or six items; one item was a singleton and the other items were identical distractors (e.g., a single cookie and three identical toy cars). At both ages, infants looked to the singletons first more often, were faster to look at singletons, and looked longer at singletons. However, when a computational model was used to quantify the relative salience of the singleton in each display-which varied widely among the different singleton-distractor combinations-we found a strong, graded effect of physical salience on attention and no evidence that singleton status per se influenced attention. In addition, consistent with other research on attention in infancy, the effect of salience was stronger for 6-month-old infants than for 8-month-old infants. Taken together, these results show that attention-getting and attention-holding in infancy vary continuously with quantitative variations in physical salience rather than depending in a categorical manner on whether an item is unique. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Association of indoor dust microbiota with cognitive function and behavior in preschool-aged children

BACKGROUND

Childhood cognitive development depends on neuroimmune interactions. Immunomodulation by early-life microbial exposure may influence neuropsychological function. In this study, we investigate the association between residential indoor microbiota and cognition and behavior among preschoolers.

RESULTS

Indoor-settled dust bacterial and fungal characteristics were assessed using 16S and ITS amplicon sequencing (microbial diversity) and qPCR measurements (microbial loads). Child behavior was assessed using four scales: peer relationship, emotional, conduct, and hyperactivity was assessed by the Strengths and Difficulties Questionnaire (SDQ). Cognitive function was assessed using four tasks of the Cambridge Neuropsychological Test Automated Battery (CANTAB) software. The first two tasks were designed to assess attention and psychomotor speed (Motor Screening (MOT) and Big/Little Circle (BLC)) and the last two to evaluate the child's visual recognition/working memory (Spatial Span (SSP) and Delayed Matching to Sample (DMS)). Among the 172 included children (age 4-6 years), we observed a 51% (95%CI;75%;9%) lower odds of children scoring not normal for hyperactivity and a decrease of 3.20% (95%CI, -6.01%; -0.30%) in BLC response time, for every IQR increase in fungal Shannon diversity. Contrarily, microbial loads were directly associated with SDQ scales and response time. For example, a 2-fold increase in Gram-positive bacterial load was associated with 70% (95%CI 18%; 156%) higher odds of scoring not normal for hyperactivity and an increase of 5.17% (95%CI 0.87%; 9.65%) in DMS response time.

CONCLUSIONS

Our findings show that early-life exposure to diverse indoor fungal communities is associated with better behavioral and cognitive outcomes, whereas higher indoor microbial load was associated with worse outcomes. Video Abstract.

Infants' anticipatory eye movements: feature-based attention guides infants' visual attention

When looking for an object, we identify it by selectively focusing our attention to a specific feature, known as feature-based attention. This basic attentional system has been reported in young children; however, little is known of whether infants could use feature-based attention. We have introduced a newly developed anticipation-looking task, where infants learned to direct their attention endogenously to a specific feature based on the learned feature (color or orientation), in 60 preverbal infants aged 7-8 months. We found that preverbal infants aged 7-8 months can direct their attention endogenously to the specific target feature among irrelevant features, thus showing the feature-based attentional selection. Experiment 2 bolstered this finding by demonstrating that infants directed their attention depending on the familiarized feature that belongs to a never-experienced object. These results that infants can form anticipation by color and orientation reflect they could drive their attention through feature-based selection.

Memory and Proactive Interference for spatially distributed items

Our ability to briefly retain information is often limited. Proactive Interference (PI) might contribute to these limitations (e.g., when items in recognition tests are difficult to reject after having appeared recently). In visual Working Memory (WM), spatial information might protect WM against PI, especially if encoding items together with their spatial locations makes item-location combinations less confusable than simple items without a spatial component. Here, I ask (1) if PI is observed for spatially distributed items, (2) if it arises among simple items or among item-location combinations, and (3) if spatial information affects PI at all. I show that, contrary to views that spatial information protects against PI, PI is reliably observed for spatially distributed items except when it is weak. PI mostly reflects items that appear recently or frequently as memory items, while occurrences as test items play a smaller role, presumably because their temporal context is easier to encode. Through mathematical modeling, I then show that interference occurs among simple items rather than item-location combinations. Finally, to understand the effects of spatial information, I separate the effects of (a) the presence and (b) the predictiveness of spatial information on memory and its susceptibility to PI. Memory is impaired when items are spatially distributed, but, depending on the analysis, unaffected by the predictiveness of spatial information. In contrast, the susceptibility to PI is unaffected by either manipulation. Visual memory is thus impaired by PI for spatially distributed items due to interference from recent memory items (rather than test items or item-location combinations).

Visual working memory in early development: a developmental cognitive neuroscience perspective

In this article, we review the literature on the development of visual working memory (VWM). We focus on two major periods of development, infancy and early childhood. First, we discuss the innovative methods that have been devised to understand how the development of selective attention and perception provide the foundation of VWM abilities. We detail the behavioral and neural data associated with the development of VWM during infancy. Next, we discuss various signatures of development in VWM during early childhood in the context of spatial and featural memory processes. We focus on the developmental transition to more adult-like VWM properties. Finally, we discuss computational frameworks that have explained the complex patterns of behavior observed in VWM tasks from infancy to adulthood and attempt to explain links between measures of infant VWM and childhood VWM.