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Theories of relations between language and conceptual development benefit from empirical evidence for concepts available in infancy, but such evidence is comparatively scarce. Here, we examine early representations of specific concepts, namely, sets of dynamic events corresponding either to predicates involving two variables with a reversible, asymmetric relation between them (such as the set of all events that correspond to a linguistic phrase like “a dog is pushing a car,”) or to comparatively simpler, one-variable predicates (such as the set of events corresponding to a phrase like “a dog is jumping.”). We develop a non-linguistic, anticipatory eye-tracking task that can be administered to both infants and adults, and we use this task to gather evidence for the formation and use of such one-and two-place-predicate classes (which we refer to as event sortals) in 12–24-mo-old infants, and in adults with and without concurrent verbal prose shadowing. Using visually similar stimuli for both the simpler (one-place) and the more complex (reversible, asymmetric, two-place) concepts, we find that infants only show evidence for forming and generalizing one-place event sortals, and, while adults succeed with both kinds in the absence of verbal shadowing, shadowing hampers their ability to form and use the asymmetric two-place event sortals. In a subsequent experiment with adults, we find that if the shadowing material is grammatically impoverished, adults now succeed in forming and using both one- and two-place event sortals. We discuss implications of these results for theories of concept acquisition, and the role of language in this process.

The somatic marker hypothesis (SMH) represents a rich neuropsychological framework to study emotion-based decision-making. It originates from early brain lesion studies using the Iowa Gambling Task (IGT), which showed that adaptive decision-making relies on intact ventromedial prefrontal cortex for the integration of so-called "hot" affective signals and rational "cold" perceptual cognitive computations. Subsequent studies over the past 20 years have provided converging evidence for the reliability and validity of the IGT in assessing decision-making in both healthy and clinical samples, although some discrepancies remain. In healthy individuals, it has been shown that differences in emotional states prior to taking the IGT result in different outcomes, thus potentially accounting for some of the variation within this group. However, the precise role of such transient modulations of emotional states remains unclear. In this study we sought to examine the role of specific induced moods under carefully controlled conditions. Accordingly, we randomly assigned 44 healthy college undergraduates to a positive, negative, or neutral affect condition in which they simultaneously viewed images and listened to music that previous studies had shown to induce specific moods. Results indicated that mood induction was successful, and the positive affect group showed a clearly different pattern of IGT performance compared to the other two groups, in that they showed a rapidly established and stable bias favoring the positive expected value (EV) card decks. The negative affect group showed significantly lower bias towards the positive EV decks, although this group was not different from the neutral affect group. Bayesian analyses confirmed these findings. While consistent with SMH, these current findings may be best understood in support of a more general effect of normal mood on cognition as outlined in the broaden-and-build theory of positive emotions.

Speech is an acoustically variable signal, and one of the sources of this variation is the presence of multiple speakers. Empirical evidence has suggested that adult listeners possess remarkably sensitive (and systematic) abilities to process speech signals, despite speaker variability. It includes not only a sensitivity to speaker-specific variation, but also an ability to utilize speaker variation with other sources of information for further processing. Recently, many studies also showed that young children seem to possess a similar capacity. This suggests continuity in the processing of speaker-dependent speech variability, and suggests that this ability could also be important for infants learning their native language. In the present paper, we review evidence for speaker variability and speech processing in adults, and speaker variability and speech processing in young children, with an emphasis on how they make use of speaker-specific information in word learning situations. Finally, we will build on these findings to make a novel proposal for the use of speaker-specific information processing in phoneme learning in infancy.

Anticipatory eye movements (AEMs) are a natural and implicit measure of cognitive processing and have been successfully used to document such important cognitive capacities as learning, categorization, and generalization, especially in infancy (McMurray & Aslin, Infancy, 6, 203–229, 2004). Here, we describe an improved AEM paradigm to automatically assess online learning on a trial-by-trial basis, by analyzing eye gaze data in each intertrial interval of a training phase. Different measures of learning can be evaluated simultaneously. We describe the implementation of a system for designing and running a variety of such AEM paradigms. Additionally, this system is capable of a wider variety of gaze-contingent paradigms, as well as implementations of standard noncontingent paradigms. Our system, Smart-T (System for Monitoring Anticipations in Real Time with the Tobii), is a set of MATLAB scripts with a graphical front end, written using the Psychophysics Toolbox. The system gathers eye gaze data using the commercially available Tobii eye-trackers via a MATLAB module, Talk2Tobii. We report a pilot study showing that Smart-T can detect 6-month-old infants’ learning of simple predictive patterns involving the disappearance and reappearance of multimodal stimuli.