Expectations of Processing Ease, Informativeness, and Accuracy Guide Toddlers' Processing of Novel Communicative Cues.

Discovering the meaning of novel communicative cues is challenging and amounts to navigating an unbounded hypothesis space. Several theories posit that this problem can be simplified by relying on positive expectations about the cognitive utility of communicated information. These theories imply that learners should assume that novel communicative cues tend to have low processing costs and high cognitive benefits. We tested this hypothesis in three studies in which toddlers (N = 90) searched for a reward hidden in one of several containers. In all studies, an adult communicated the reward's location with an unfamiliar and ambiguous cue. We manipulated the processing costs (operationalized as inferential chain length) and cognitive benefits (operationalized as informativeness) of the possible interpretations of the cues. Toddlers processing of novel communicative cues were guided by expectations of low processing costs (Study 1) and high cognitive benefits (Studies 2 and 3). More specifically, toddlers treated novel cues as if they were easy to process, informative, and accurate, even when provided with repeated evidence to the contrary. These results indicate that, from toddlerhood onward, expectations of cognitive utility shape the processing of novel communicative cues. These data also reveal that toddlers, who are in the process of learning the language and communicative conventions of people around them, exert a pressure favoring cognitive efficiency in communicative systems.

Knowledge in Sight: Toddlers Plan Efficient Epistemic Actions by Anticipating Learning Gains.

Anticipating the learning consequences of actions is crucial to plan efficient information seeking. Such a capacity is needed for learners to determine which actions are most likely to result in learning. Here, we tested the early ontogeny of the human capacity to anticipate the amount of learning gained from seeing. In study 1, we tested infants' capacity to anticipate the availability of sight. Fourteen-month-old infants (N = 72) were invited to search for a toy hidden inside a container. The participants were faster to attempt at opening a shutter when this action allowed them to see inside the container. Moreover, this effect was specifically observed when seeing inside the container was potentially useful to the participants' goals. Thus, infants anticipated the availability of sight, and they calibrated their information-seeking behaviors accordingly. In studies 2 and 3, we tested toddlers' capacity to anticipate whether data would be cognitively useful for their goals. Two-and-a-half-year-olds (N = 72) had to locate a target character hidden among distractors. The participants flipped the characters more often, and were comparatively faster to initiate this action when it yielded access to visual data allowing them to locate the target. Thus, toddlers planned their information-seeking behaviors by anticipating the cognitive utility of sight. In contrast, toddlers did not calibrate their behaviors to the cognitive usefulness of auditory data. These results suggest that cognitive models of learning guide toddlers' search for information. The early developmental onset of the capacity to anticipate future learning gains is crucial for active learning.

How do we interpret questions? Simplified representations of knowledge guide humans' interpretation of information requests.

This paper investigates the cognitive mechanisms supporting humans' interpretation of requests for information. Learners can only search for a piece of information if they know that they are ignorant about it. Thus, in principle, the interpretation of requests for information could be guided by representations of Socratic ignorance (tracking what people know that they do not know). Alternatively, the interpretation of requests for information could be simplified by relying primarily on simple knowledge tracking (i.e., merely tracking what people know). We judged these hypotheses by testing two-and-a-half-year-old toddlers (N = 18), five- to seven-year-old children (N = 72), and adults (N = 384). In our experiments, a speaker asked a question that could be disambiguated by tracking her state of knowledge. We manipulated the speakers' visuals to modulate the complexity of the ignorance representation required to disambiguate their questions. Toddlers showed no tendency to appeal to representations of Socratic ignorance when disambiguating questions (Pilot S1). Five- to seven-year-olds exhibited a similar pattern of results, and they performed better when information requests could be disambiguated using simple knowledge tracking (Studies 1a-1b). Adults used representations of Socratic ignorance to interpret questions, but were more confident when simple knowledge tracking was sufficient to disambiguate information requests (Studies 2-3). Moreover, adults disambiguated questions as if speakers could request information about things that they were ignorant of, even when speakers had no reason to know about their ignorance (Studies 3-4). Thus, the interpretation of requests for information rests primarily on simple knowledge tracking-and not on representations of Socratic ignorance-a heuristic that reduces processing costs.

Nonverbal rhetoric: 2- to 4-year-old children select relevant evidence when trying to influence others.

This article investigates the early emergence of reason-giving. Toddlers are sensitive to disagreements, and they can track several kinds of informational access, such as visual perception. We investigated whether young children use these skills (a) when assessing whether providing reasons is needed and (b) when selecting appropriate behaviors to support their claims. An experimenter disagreed with 2- to 4-year-old children (N = 71) about the location of a toy placed in 1 of 4 boxes. In the fully transparent condition, the boxes were transparent, and the toy was visible to the experimenter and to the participant. In the window condition, the boxes were partially opaque, and the toy was initially hidden from the experimenter but visible to the participant through a transparent window. In this condition, toddlers could make the toy visible to the experimenter by rotating the baited box. Participants in the window condition were more likely to rotate the baited box than those in the transparent condition. Thus, children were more likely to rotate the box when this action was an efficient way of supporting their claims by revealing new and relevant information to the experimenter. These results demonstrate the presence of precursors of crucial skills required for reason-giving and reveal that from 2 years of age, children do not use fixed persuasion strategies. Instead, they select relevant evidence when attempting to influence others. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Infants discriminate the source of social touch at stroking speeds eliciting maximal firing rates in CT-fibers.

The evaluation of interpersonal touch is heavily influenced by its source. For example, a gentle stroke from a loved one is generally more pleasant than the same tactile stimulation from a complete stranger. Our study tested the early ontogenetic roots of humans' sensitivity to the source of interpersonal touch. We measured the heart rate of three groups of nine-month-olds while their legs were stroked with a brush. The participants were stroked at a different speed in each group (0.3 cm/s, 3 cm/s, 30 cm/s). Depending on the Identity condition (stranger vs. parent), the person who acted as if she was stroking the infant's leg was either an unfamiliar experimenter or the participant's caregiver. In fact, the stimulation was always delivered by a second experimenter blind to the Identity condition. Infants' heart rate decreased more in reaction to strokes when their caregiver rather than a stranger acted as the source of the touch. This effect was found only for tactile stimulations whose velocity (3 cm/s) is known to elicit maximal mean firing rates in a class of afferents named C-tactile fibers (CTs). Thus, the infants' reaction to touch is modulated not just by its mechanical properties but also by its social source.