Understanding how infants perceive real-world scenes and the type of information they rely on when recognizing different kinds of scenes remains unexplored. In this study, we aimed to investigate the relationship between action and scene information in infants. In a preferential looking paradigm, 18-month-olds were exposed to several trials in which they observed a human performing a given action and a subsequent simultaneous display of two scenes. One of the scenes was congruent with the action, representing the environment where the action is more likely to occur, whereas the other was incongruent. Results revealed a significant preference for looking at the congruent scene, accompanied by a longer first visit duration of that scene. Our findings show that the relation between action and scene information, previously reported for adults, is present already in infancy, suggesting a potential role of action information in shaping the construal of scene representation.

Studies suggest that infants track others' beliefs based on visual information (Scott & Baillargeon, 2017 but see Dörrenberg, Rakoczy, Liszkowski, 2018). However, research targeting whether infants understand that others' beliefs can be induced via communication is scarce, although most of the human belief-repertoire is acquired via communication. We presented eighteen-month-olds (Experiment1:N=34; Experiment2-replication:N=35) with a false belief (FB) scenario where the initial belief was induced via communication, aiming to measure their informative pointing (for an agent mistaken about a toy's location compared to a true belief scenario). Instead of more pointing to the toy's current location, in the FB condition we found an unexpected ‚Äòaltercentric' effect: infants pointed more to the empty location where the agent falsely believed the object to be). Next, we asked whether infants show different altercentric effects for visually induced beliefs (Experiment3: N=35). Results replicated the altercentric effect, suggesting a potentially stronger encoding of visually induced beliefs.

Although infants can frequently observe others gathering information, it is an open question whether and how they make sense of such activities since the mental causes and intended effects of these are hidden and underdetermined by the available evidence. We tested the hypothesis that infants possess a naive theory that leads them to grasp the purpose of information-gathering actions when they serve as sub-goals of higher-order instrumental goals. We presented 14-month-old infants with actions that were inefficient with respect to the agent’s instrumental goal but could or could not be justified as information-seeking behavior via this theory. We expected longer looks in the condition where the detour could not be justified and the results were in line with our predictions. While this evidence is compatible with our hypothesis, further studies are in progress to rule out alternative interpretations of our findings.

The meaning of complex expressions (“two apples”) is computed by accessing and combining the concepts linked to their constituent words (“two”, “apples”). Across three eye-tracking experiments (N = 60), we demonstrate that preverbal infants can perform such computations and successfully derive the meaning of novel quantified noun phrases. Experiment 1 established that 12-month-olds can learn two distinct novel labels (pseudowords) denoting a singleton or a pair. Experiments 2-3 indicated that infants combine the meanings of the newly learnt quantity labels with those of familiar kind labels. When presented with four potential referents (e.g., 1duck, 2ducks, 1ball, 2balls) and asked to look at one ball, infants oriented to the target satisfying the meaning of both labels (1ball) over the distractors satisfying the meaning of the labels separately (2balls, 1duck). Conceptual combination skills that enable complex thought seem to be operational in infancy, and can be triggered by linguistic stimuli.

Abstract combinatorial thought supports adult human reasoning. But it is unknown whether such thought is available to infants who are in the process of acquiring their native language. In a series of three experiments, we ask whether 12-month-old pre-verbal infants have access to a propositional negation operator, as a defining hallmark of abstract combinatorial thought. We examine infants’ understanding of disjunctive reasoning problems, taking the insight that some impossible outcomes are supported by negation, while others may not be. We thus introduce a novel use of the Violation of Expectation paradigm, with visual stimuli which build on the Call (2004) cup task by expanding the range of possibilities and testing different kinds of inconsistent outcomes. Results from three experiments do not provide direct support for the view that infants possess a propositional negation operator, but they are more compatible with it than alternatives.

Research on infants' observational behavior has predominantly focused on retrospective information gain, leaving the role of prospective evaluation of information gain unclear. We examined 12-month-olds' use of information sources in an eye-tracking study, where participants could use their gaze to 'shake' two out of three boxes to locate a hidden character through auditory cues. Across two pre-registered experiments, we manipulated the probability distributions for character locations to assess forward-looking exploratory strategies. Findings from Experiment 1 with a uniform distribution suggest that while infants learned task contingencies, their choices did not align with maximizing expected information gain, leaning instead towards confirmatory hypothesis testing. Experiment 2 employs a non-uniform probability distribution for character locations to rule out alternative explanations of Experiment 1. In this setup, one box pair provides more information gain, while the other provides confirmatory evidence. Data collection is in progress, results will be presented at the conference.

The productivity of the human mind is rooted in the ability to flexibly combine concepts and computations. Developmental origins of this ability remain poorly understood. In two looking-time experiments, we investigated whether 15-month-olds (N = 48) can learn two distinct functions and compose them. We used a tool that transformed objects: it had two functions (i.e., it changed the kind of the object that went inside, or duplicated it), each triggered by a different handle. Experiment 1 showed that infants could learn both functions: at test, they looked longer when the outcome of the handle manipulation did not match the performed action than when it did. In Experiment 2, following a familiarization with individual manipulations and their outcomes, both manipulations were performed simultaneously at test. Infants displayed surprise when the outcome was inconsistent with a function composition. Infants readily learn two novel functions and spontaneously combine their outcomes.

Human adults are extremely good at inferring the overall meaning of scenes in a single glanceÑtheir gistÑsuch as "a park" or "a kitchen". However, little is known about categorical knowledge of scenes and the extraction of scene gist in development. In two preferential-looking experiments, we investigated whether 12- and 18-month-old infants categorize scenes based on gist and the role that verbal input plays in extracting such conceptual commonality. Whereas 12-month-olds showed no evidence of scene categorization, 18-month-olds categorized scenes when the images were presented with a label void of meaning in the familiarization phase. The observed facilitating effect of language on categorization, previously already shown in studies with objects, seems to emerge at a later age for scenes, possibly due to their inherent complexity. Our findings show for the first time that by the age of 18 months, infants can categorize visual scenes based on abstract commonalities.

Humans are ultra-social: they spontaneously incorporate others’ mental states into their action-planning (Kaminski et al.,2008), and altercentric: their behavior is influenced by others’ perspectives, even perspectives irrelevant to their instrumental goal (Kampis & Southgate, 2020). Recent evidence suggests that similarly to human infants, non-human great apes anticipate others’ actions based on their beliefs (Krupenye et al.,2016; Kano et al, 2019); raising the critical question whether altercentrism is uniquely human. In two experiments, we tested chimpanzees, bonobos, and orangutans in a manual search paradigm adapted from Mendes et al. (2008). These experiments replicated findings demonstrating apes’ first-person object-tracking abilities. Experiment 1 found no evidence for altercentrism: apes’ search behavior was not spontaneously modulated by another agent’s beliefs (unlike 14-month-old human infants; Kampis & Kovács, 2020). Experiment 2 found tentative evidence that apes inferred a person’s actions based on her beliefs, and adapted their own actions based on this information.

From the earliest months of life, infants prefer listening to and learn better from infant-directed speech (IDS) than adult-directed speech (ADS). Yet, IDS differs within communities, across languages, and across cultures, both in form and in prevalence. This large-scale, multi-site study used the diversity of bilingual infant experiences to explore the impact of different types of linguistic experience on infants' IDS preference. As part of the multi-lab ManyBabies 1 project, we compared lab-matched samples of 333 bilingual and 385 monolingual infants' preference for North-American English IDS (cf. ManyBabies Consortium, 2020: ManyBabies 1), tested in 17 labs in 7 countries. Those infants were tested in two age groups: 6-9 months (the younger sample) and 12-15 months (the older sample). We found that bilingual and monolingual infants both preferred IDS to ADS, and did not differ in terms of the overall magnitude of this preference. However, amongst bilingual infants who were acquiring North-American English (NAE) as a native language, greater exposure to NAE was associated with a stronger IDS preference, extending the previous finding from ManyBabies 1 that monolinguals learning NAE as a native language showed a stronger preference than infants unexposed to NAE. Together, our findings indicate that IDS preference likely makes a similar contribution to monolingual and bilingual development, and that infants are exquisitely sensitive to the nature and frequency of different types of language input in their early environments.