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…

Infant research is providing accumulating evidence that number-space mappings appear early in development. Here, a Posner cueing paradigm was used to investigate the neural mechanisms underpinning the attentional bias induced by nonsymbolic numerical cues in 9-month-old infants (N = 32). Event-related potentials and saccadic reaction time were…

Children with autism spectrum disorder (ASD) display difficulties with response to joint attention in natural settings but often perform comparably to typically developing (TD) children in experimental studies of gaze following. Previous work comparing infants at elevated likelihood for ASD versus TD infants has manipulated aspects of the gaze…

In direct interactions with others, 9-month-old infants' learning about objects is facilitated when the interaction partner addresses the infant through eye contact before looking toward an object. In this study we investigated whether similar factors promote infants' observational learning from third-party interactions. In Experiment 1,…

Parents support and scaffold more mature behaviors in their infants. Recent research suggests that parent-infant joint visual attention may scaffold the development of sustained attention by extending the duration of an infant's attention to an object. The open question concerns the parent behaviors that occur within joint-attention episodes and…

From early in life, infants synchronize with others on a physiological level, a process thought to underlie social connections and group cohesion. This synchronization is seen, for example, when their pupils dilate in response to observing another person with dilated pupils -- known as "pupillary contagion." There is mixed evidence on…

Adults use both bottom-up sensory inputs and top-down signals to generate predictions about future sensory inputs. Infants have also been shown to make predictions with simple stimuli and recent work has suggested top-down processing is available early in infancy. However, it is unknown whether this indicates that top-down prediction is an ability…

Since birth, infants develop the ability to perceive a wide range of intersensory relations among various kinds of amodal temporal information. This study addresses the development of the ability to perceive duration-based intersensory relations. Three groups of infants, four, seven and 10 months old, participated in two trials of an intersensory…

Bilingualism has been observed to influence cognitive processing across the lifespan but whether bilingual environments have an effect on selective attention and attention strategies in infancy remains an unresolved question. In Study 1, infants exposed to monolingual or bilingual environments participated in an eye-tracking cueing task in which…

The 4 experiments reported here used the preferential looking and habituation paradigms to examine whether 5-month-olds possess a perceptual template for snakes, sharks, and rodents. It was predicted that if infants possess such a template, then they would attend preferentially to schematic images of these nonhuman animal stimuli relative to…

Visual attention in complex, dynamic scenes is attracted to locations that contain socially relevant features, such as faces, and to areas that are visually salient. Previous work suggests that there is a "global shift" over development such that observers increasingly attend to faces with age. However, no prior work has tested whether…

To learn a language infants must learn to link arbitrary sounds to their meaning. While words are the clearest example of this link, they are not the only component of language; morphological regularities (e.g., the plural -s suffix in English) carry meaning as well. Comprehensive theories of language acquisition must account for how infants build…

Two experiments examined whether 4-month-olds (n = 120) who were induced to assign two objects to different categories would then be able to take advantage of these contrastive categorical encodings to individuate and track the objects. In each experiment, infants first watched functional demonstrations of two tools, a masher and tongs (Experiment…

This experiment tests the age at which left-to-right spatial associations found in infancy shift to culture-specific spatial biases in later childhood, for both numerical and non-numerical information. Children ages 1-5 years (N = 320) were tested within an eye-tracking paradigm which required passive viewing of a video portraying a spatial…

Toddlerhood is marked by advances in several lexico-semantic skills, including improvements in the size and structure of the lexicon and increased efficiency in lexical processing. This project seeks to delineate how early changes in vocabulary size and vocabulary structure support lexical processing (Experiment 1), and how these three skills…