The boundary effect, namely the infants' failures to compare small and large numerosities, is well documented in studies using visual stimuli. The prevailing explanation is that the numerical system used to process sets up to 3 is incompatible with the system employed for numbers >3. This study investigates the boundary effect in 10-month-old…

Studies on the emergence of effects of socioeconomic inequality typically report that socioeconomic background is positively associated with early cognitive abilities. However, studies on looking behaviour in habituation tasks rarely investigate this association, although such tasks are standard in measuring cognitive abilities in infants. The…

Traditionally, the exogenous control of gaze by external saliencies and the endogenous control of gaze by knowledge and context have been viewed as competing systems, with late infancy seen as a period of strengthening top-down control over the vagaries of the input. Here we found that one-year-old infants control sustained attention through head…

Mental rotation, the cognitive process of moving an object in mind to predict how it looks in a new orientation, is coupled to intelligence, learning, and educational achievement. On average, adolescent and adult males solve mental rotation tasks slightly better (i.e., faster and/or more accurate) than females. When such behavioral differences…

Research with Western samples has uncovered the rapid development of infants' visual attention. This study evaluated spatial attention in 6- to 9-month-old infants living in rural Malawi (N = 511; n[subscript Boys] = 255, n[subscript Yao] = 427) or suburban California, United States (N = 57, n[subscript Boys] = 29, n[subscript White] = 37) in…

The ability to perceive approximate numerosity is present in many animal species, and emerges early in human infants. Later in life, it is moderately heritable and associated with mathematical abilities, but the etiology of the Approximate Number System (ANS) and its degree of independence from other cognitive abilities in infancy is unknown.…

A bilingual environment is associated with changes in the brain's structure and function. Some suggest that bilingualism also improves higher-cognitive functions in infants as young as 6-months, yet whether this effect is associated with changes in the infant brain remains unknown. In the present study, we measured brain activity using functional…

Science, Technology, Engineering, and Math (STEM) education is essential to the economic growth, health, and progress of the modern world. One cognitive ability that underpins thinking and learning in STEM, as well as other disciplines, is relational ability. This ability to spot common relations shared by different objects, events, ideas, or…

Is early reasoning about an agent's knowledge best characterized by a mentalistic stance, a teleological stance, or both? In this research, 5-month-old infants (N = 64, 50% female, 83% White) saw a novel eyeless agent consistently approach object-A as opposed to object-B. Although infants could always see both objects, a screen separated object-B…

This study explored child behaviours that enable mothers to perceive their child's minds. We administered the Mind Perception Questionnaire to 216 women with children aged between 0 and 24 months and 221 working women without children. Participants responded with mind perceptions for various entities, including for their children (a 0--2-year-old…

Purpose: This study aims to examine the development of auditory selective attention to speech in noise by examining the ability of infants to prefer child-directed speech (CDS) over time-reversed speech (TRS) presented in "on-channel" and "off-channel" noise. Method: A total of 32 infants participated in the study. Sixteen…

The development of skills related to executive function (EF) in infancy, including their emergence, underlying neural mechanisms, and interconnections to other cognitive skills, is an area of increasing research interest. Here, we report on findings from a multidimensional dataset demonstrating that infants' behavioral performance on a flexible…

Infancy is a pivotal time in the development of a human's cognitive ability. There is a lack of research in this area, specifically on mothers and their beliefs about literacy practices and the home learning environment. By utilizing Bronfenbrenner's ecological framework, this study explores the beliefs of mothers and how they impact the infants'…

Early childhood is a critical period characterized by rapid development of motor and language skills. Reliably assessing motor and language development in early childhood is difficult, and there is a lack of agreement on measurement tool use. This scoping review aims to identify measurement tools used to examine motor and language skills in…

This study examines the extent to which iron deficiency in infancy contributes to adverse neurocognitive and educational outcomes in young adulthood directly and indirectly, through its influence on verbal cognition and attention problems in childhood. Young adults (N = 1,000, M age = 21.3 years, 52% female; of Spanish or indigenous descent) from…