Children's suggestibility in relation to their understanding about sources of knowledge

The effect of source claims on statement believability and speaker accountability

What is the effect of source claims (such as "I saw it" or "Somebody told me") on the believability of statements, and what mechanisms are responsible for this effect? In this study, we tested the idea that source claims impact statement believability by modulating the extent to which a speaker is perceived to be committed to (and thereby accountable for) the truth of her assertion. Across three experiments, we presented participants with statements associated with different source claims, asked them to judge how much they believed the statements, and how much the speaker was responsible if the statement turned out to be false. We found that (1) statement believability predicted speaker accountability independently of a statement's perceived prior likelihood or associated source claim; (2) being associated with a claim to first-hand ("I saw that . . .") or second-hand ("Somebody told me that . . .") evidence strengthened this association; (3) bare assertions about specific circumstances were commonly interpreted as claims to first-hand evidence; and (4) (everything else being equal) claims to first-hand evidence increased while claims to second-hand evidence decreased both statement believability and speaker accountability. These results support the idea that the believability of a statement is closely related to how committed to its truth the speaker is perceived to be and that source claims modulate the extent of this perceived commitment.

The Developmental Differences of Implicit Theory of Mind in Infants Using Anticipatory Looking Paradigm

Objectives: This study examined the developmental differences of implicit theory of mind in infants aged 12 to 24 months according to two types of tasks within the anticipatory looking paradigm, as well as the interaction between age group and type of task.Methods: In all, 69 infants participated in this study aged 12, 18, and 24 months. Two types of implicit false-belief tasks using an anticipatory looking paradigm were administered to all the infants for about 4 minutes 20 seconds. While all of the infants watched two types of computerized video clips (FB1, FB2) through the computer screen, an eye-tracker (TobiiX120) recorded the traces of anticipatory looking of infants. The anticipatory looking of infants in test trials was then analyzed.Results: Results showed that the differences between the 12-month-olds and the other age groups (18-month-olds, 24-month-olds) were significant, but even some of the 12-month-olds showed evidence of an implicit theory of mind. The level of implicit theory of mind of 18-month infants did not significantly differ from that of 24-month infants. In addition, a difference by type of implicit false-belief task was significant. Infants showed a higher level of implicit theory of mind in Task1 (FB1) than in Task2 (FB2). However, the interaction effect between age and type of task was not significant.Conclusion: The findings of this study hold implications for the development of implicit theory of mind early in life, and indicate the validity of the anticipatory looking paradigm with two types of tasks. Several limitations and suggestions for future study are also presented.

The effect of disagreement on children's source memory performance

Source representations play a role both in the formation of individual beliefs as well as in the social transmission of such beliefs. Both of these functions suggest that source information should be particularly useful in the context of interpersonal disagreement. Three experiments with an identical design (one original study and two replications) with 3- to 4-year-old-children (N = 100) assessed whether children's source memory performance would improve in the face of disagreement and whether such an effect interacts with different types of sources (first- vs. second-hand). In a 2 x 2 repeated-measures design, children found out about the contents of a container either by looking inside or being told (IV1). Then they were questioned about the contents of the container by an interlocutor puppet who either agreed or disagreed with their answer (IV2). We measured children's source memory performance in response to a free recall question (DV1) followed by a forced-choice question (DV2). Four-year-olds (but not three-year-olds) performed better in response to the free recall source memory question (but not the forced-choice question) when their interlocutor had disagreed with them compared to when it had agreed with them. Children were also better at recalling 'having been told' than 'having seen'. These results demonstrate that by four years of age, source memory capacities are sensitive to the communicative context of assertions and serve social functions.

The pragmatic role of trust in young children's interpretation of unfamiliar signals

What role does children’s trust in communication play in their acquisition of new meanings? To answer, we report two experimental studies (N = 81) testing how three- to four-year-olds interpret the meaning of a novel communicative device when it is used by a malevolent and potentially deceptive informant. Children participated in a hiding game in which they had to find a reward hidden in one of two boxes. In the initial phase of the experiments, a malevolent informant always indicated the location of the empty box using a novel communicative device, either a marker (Study 1), or an arrow (Study 2). During that phase, 3- and 4-year-olds learned to avoid the box indicated by the novel communicative device. In the second phase of the test, the malevolent informant was replaced by a benevolent one. Nevertheless, children did not change their search strategy, and they kept avoiding the box tagged by the novel communicative device as often as when it had been produced by the malevolent informant. These results suggest that during the initial phase, children (i) did not consider the possibility that the malevolent informant might intend to deceive them, and (ii) did not ignore the unfamiliar communicative signal or treat it as irrelevant. Instead, children relied on the unfamiliar communicative signal to locate the empty box’s location. These results suggest that children’s avoidance of the location indicated by an unfamiliar signal is not unambiguous evidence for distrust of such signal. We argue that children’s trust in ostensive communication is likely to extend to unfamiliar communicative means, and that this presumption of trustworthiness plays a central role in children’s acquisition of new meanings.

Children's Naive Concepts of OCD and How They Are Affected by Biomedical Versus Cognitive Behavioural Psychoeducation

BACKGROUND

How we conceptualize mental health conditions is important as it impacts on a wide range of mediators of treatment outcome. We do not know how children intuitively conceptualize obsessive-compulsive disorder (OCD), nor do we know the relative impact of biomedical or cognitive behavioural conceptual explanations, yet both are being widely used in psychoeducation for children with OCD.

AIMS

This study identified children's naive concepts of OCD, and the comparative impact of biomedical versus cognitive behavioural psychoeducation on perceived prognosis.

METHOD

A within- and between-subjects experimental design was used. After watching a video of a young person describing their OCD, 202 children completed a questionnaire examining their concepts of the condition. They repeated the questionnaire following a second equivalent video, this time preceded by either biomedical or cognitive behavioural psychoeducation.

RESULTS

Participants' naive concepts of OCD reflected predominant models of OCD in healthcare. Even at the minimal dose of psychoeducation, participants' conceptualizations of OCD changed. Prior exposure to OCD resulted in a stronger alignment with the biomedical model. Exposure to biomedical psychoeducation resulted in participants predicting a slower recovery with less chance of complete remission.

CONCLUSION

Psychoeducation for childhood OCD is impactful. Despite its wide use by clinicians and mental health services, biomedical psychoeducation appears to have deleterious effects. Children's concepts of OCD merit attention but caution should be applied in how they are targeted.

Recollection improves with age: children's and adults' accounts of their childhood experiences

Since the time of Freud, psychologists have drawn conclusions about children's memory on the basis of retrospective research with adults. Here, we turn the tables by examining what prospective studies with children and adolescents can tell us about the retrospective memory accounts provided by adults. Adults were interviewed about recent events and events from different points during their childhood (Age 5, Age 10) and early adolescence (Age 13). Children (5- and 8- to 9-year-olds) and young adolescents (12- to 13-year-olds) were interviewed about recent events. When matched for age at the time of encoding, adults recalled more about the target events than did 5-year-olds, even though the retention interval for adults was substantially longer. We conclude that retrospective studies with adults may lead researchers to overestimate the content of the early childhood memories that survive. We discuss the theoretical implications of these findings for an understanding of memory development and the practical implications for the interpretation of adults' retrospective accounts in the courtroom.

What is it to remember?

In response to the commentaries, we clarify and defend our characterization of both the nature and function of episodic memory. Regarding the nature of episodic memory, we extend the distinction between event and episodic memory and discuss the relational role of episodic memory. We also address arguments against our characterization of autonoesis and argue that, while self-referential, it needs to be distinguished from an agentive notion of self. Regarding the function of episodic memory, we review arguments about the relation between future mental time travel and memory veridicality; clarify the relation between autonoesis, veridicality, and confidence; and finally discuss the role of episodic memory in diachronic commitments.

Parameterizing developmental changes in epistemic trust

Children rely on others for much of what they learn, and therefore must track who to trust for information. Researchers have debated whether to interpret children's behavior as inferences about informants' knowledgeability only or as inferences about both knowledgeability and intent. We introduce a novel framework for integrating results across heterogeneous ages and methods. The framework allows application of a recent computational model to a set of results that span ages 8 months to adulthood and a variety of methods. The results show strong fits to specific findings in the literature trust, and correctly fails to fit one representative result from an adjacent literature. In the aggregate, the results show a clear development in children's reasoning about informants' intent and no appreciable changes in reasoning about informants' knowledgeability, confirming previous results. The results extend previous findings by modeling development over a much wider age range and identifying and explaining differences across methods.

The Development of Selective Copying: Children's Learning From an Expert Versus Their Mother

This study tested the prediction that, with age, children should rely less on familiarity and more on expertise in their selective social learning. Experiment 1 (N = 50) found that 5- to 6-year-olds copied the technique their mother used to extract a prize from a novel puzzle box, in preference to both a stranger and an established expert. This bias occurred despite children acknowledging the expert model's superior capability. Experiment 2 (N = 50) demonstrated a shift in 7- to 8-year-olds toward copying the expert. Children aged 9-10 years did not copy according to a model bias. The findings of a follow-up study (N = 30) confirmed that, instead, they prioritized their own-partially flawed-causal understanding of the puzzle box.

Japanese and Canadian Children's Beliefs about Child and Adult Knowledge: A Case for Developmental Equifinality?

Children do not know everything that adults know, nor do adults know everything that children know. The present research examined the universality of beliefs about child and adult knowledge and their development with 4- and 7-year-old Canadian and Japanese children (N = 96). In both countries, all children were able to identify adult-specific knowledge and only older children displayed beliefs about child-specific knowledge. However, Japanese and Canadian children differed in whether they used their own knowledge in deciding whether a person who knew an item was a child or an adult. In addition, parental and child beliefs were related in Japan but not in Canada. These findings indicate that children growing up in different cultures may take different paths in developing beliefs about age-related knowledge. Implications for theories of socio-cognitive development and learning are discussed.

Reasoning about knowledge: Children's evaluations of generality and verifiability

In a series of experiments, we examined 3- to 8-year-old children's (N=223) and adults' (N=32) use of two properties of testimony to estimate a speaker's knowledge: generality and verifiability. Participants were presented with a "Generic speaker" who made a series of 4 general claims about "pangolins" (a novel animal kind), and a "Specific speaker" who made a series of 4 specific claims about "this pangolin" as an individual. To investigate the role of verifiability, we systematically varied whether the claim referred to a perceptually-obvious feature visible in a picture (e.g., "has a pointy nose") or a non-evident feature that was not visible (e.g., "sleeps in a hollow tree"). Three main findings emerged: (1) young children showed a pronounced reliance on verifiability that decreased with age. Three-year-old children were especially prone to credit knowledge to speakers who made verifiable claims, whereas 7- to 8-year-olds and adults credited knowledge to generic speakers regardless of whether the claims were verifiable; (2) children's attributions of knowledge to generic speakers was not detectable until age 5, and only when those claims were also verifiable; (3) children often generalized speakers' knowledge outside of the pangolin domain, indicating a belief that a person's knowledge about pangolins likely extends to new facts. Findings indicate that young children may be inclined to doubt speakers who make claims they cannot verify themselves, as well as a developmentally increasing appreciation for speakers who make general claims.

Children's picture interpretation: Appearance or intention?

Pictures are defined by their creator’s intentions and resemblance to their real world referents. Here we examine whether young children follow a realist route (e.g., focusing on how closely pictures resemble their referents) or intentional route (e.g., focusing on what a picture is intended to represent by its artist) when identifying a picture’s referent. In 3 experiments, we contrasted an artist’s intention with her picture’s appearance to investigate children’s use of appearance and intentional cues. In Experiment 1, children aged 3–4 and 5–6 years (N = 151) were presented with 4 trials of 3-object arrays (e.g., a pink duck, a blue duck, and a teddy). The experimenter photographed or drew 1 of the objects (e.g., blue duck), however, the subsequent picture depicted the referent in grayscale (black and white condition) or the color of its shape-matched object, for example, a pink duck (color change condition). Children were asked 3 questions regarding the identity of the pictures; responses were guided by intentional cues in the black and white condition, but appearance in the color change condition. Experiment 2 confirmed that appearance responses were not due to the artist’s changing knowledge state. Experiment 3 replicated the results of Experiment 1 with adult participants. Together, these studies show that children and adults are neither strictly realist nor intentional route followers. They are realists until resemblance cues fail, at which point they defer to intentional cues.

Young children heed advice selectively

A rational strategy to update and revise one's uncertain beliefs is to take advice by other agents who are better informed. Adults routinely engage in such advice taking in systematic and selective ways depending on relevant characteristics such as reliability of advisors. The current study merged research in social and developmental psychology to examine whether children also adjust their initial judgment to varying degrees depending on the characteristics of their advisors. Participants aged 3 to 6 years played a game in which they made initial judgments, received advice, and subsequently made final judgments. They systematically revised their judgments in light of the advice, and they did so selectively as a function of advisor expertise. They made greater adjustments to their initial judgment when advised by an apparently knowledgeable informant. This suggests that the pattern of advice taking studied in social psychology has its roots in early development.

Not So Innocent

Adults’ social evaluations are influenced by their perception of other people’s competence and motivation: Helping when it is difficult to help is praiseworthy, and not helping when it is easy to help is reprehensible. Here, we look at whether children’s social evaluations are affected by the costs that agents incur. We found that toddlers can use the time and effort associated with goal-directed actions to distinguish agents, and that children prefer agents who incur fewer costs in completing a goal. When two agents refuse to help, children retain a preference for the more competent agent but infer that the less competent agent is nicer. These results suggest that children value agents who incur fewer costs, but understand that failure to engage in a low-cost action implies a lack of motivation. We propose that a naive utility calculus underlies inferences from the costs and rewards of goal-directed action and thereby supports social cognition.

Early testimonial learning: monitoring speech acts and speakers

Testimony provides children with a rich source of knowledge about the world and the people in it. However, testimony is not guaranteed to be veridical, and speakers vary greatly in both knowledge and intent. In this chapter, we argue that children encounter two primary types of conflicts when learning from speakers: conflicts of knowledge and conflicts of interest. We review recent research on children's selective trust in testimony and propose two distinct mechanisms supporting early epistemic vigilance in response to the conflicts associated with speakers. The first section of the chapter focuses on the mechanism of coherence checking, which occurs during the process of message comprehension and facilitates children's comparison of information communicated through testimony to their prior knowledge, alerting them to inaccurate, inconsistent, irrational, and implausible messages. The second section focuses on source-monitoring processes. When children lack relevant prior knowledge with which to evaluate testimonial messages, they monitor speakers themselves for evidence of competence and morality, attending to cues such as confidence, consensus, access to information, prosocial and antisocial behavior, and group membership.

Is tool-making knowledge robust over time and across problems?

In three studies, we explored the retention and transfer of tool-making knowledge, learnt from an adult demonstration, to other temporal and task contexts. All studies used a variation of a task in which children had to make a hook tool to retrieve a bucket from a tall transparent tube. Children who failed to innovate the hook tool independently saw a demonstration. In Study 1, we tested children aged 4–6 years (N = 53) who had seen the original demonstration 3 months earlier. Performance was excellent at the second time, indicating that children’s knowledge was retained over the 3 month period. In Studies 2 and 3 we explored transfer of the new knowledge to other tasks. In Study 2, children were given two variants of the apparatus that differed in surface characteristics (e.g., shape and color). Participants generalized their knowledge to these new apparatuses even though the new pipecleaner also differed in size and color. Five- to 6-year-olds (N = 22) almost always transferred their knowledge to problems where the same tool had to be made. Younger, 3- to 5-year-olds’ (N = 46), performance was more variable. In Study 3, 4- to 7-year-olds (N = 146) saw a demonstration of hook making with a pipecleaner, but then had to make a tool by combining pieces of wooden dowel (or vice versa: original training on dowel, transfer to pipecleaner). Children did not transfer their tool-making knowledge to the new material. Children retained tool-making knowledge over time and transferred their knowledge to new situations in which they needed to make a similar tool from similar materials, but not different materials. We concluded that children’s ability to use tool-making knowledge in novel situations is likely to depend on memory and analogical reasoning, with the latter continuing to develop during middle childhood.

First-hand sensory experience plays a limited role in children's early understanding of seeing and hearing as sources of knowledge: evidence from typically hearing and deaf children

One early-developing component of theory of mind is an understanding of the link between sensory perception and knowledge formation. We know little about the extent to which children's first-hand sensory experiences drive the development of this understanding, as most tasks capturing this early understanding target vision, with less attention paid to the other senses. In this study, 64 typically hearing children (Mage  = 4.0 years) and 21 orally educated deaf children (Mage  = 5.44 years) were asked to identify which of two informants knew the identity of a toy animal when each had differing perceptual access to the animal. In the 'seeing' condition, one informant saw the animal and the other did not; in the 'hearing' condition, one informant heard the animal and the other did not. For both hearing and deaf children, there was no difference between performance on hearing and seeing trials, but deaf children were delayed in both conditions. Further, within both the hearing and deaf groups, older children outperformed younger children on these tasks, indicating that there is a developmental progression. Taken together, the pattern of results suggests that experiences other than first-hand sensory experiences drive children's developing understanding that sensory perception is associated with knowledge.

Children's trust in unexpected oral versus printed suggestions: limitations of the power of print

Children have a bias to trust spoken testimony, yet early readers have an even stronger bias to trust print. Here, we ask how enduring is the influence of printed testimony: Can the learning be applied to new scenarios? Using hybrid pictures more dominant in one animal species (e.g., squirrel) than another (e.g., rabbit), we examined 3-6-year-olds' (N = 130) acceptance of an unexpected, non-dominant label suggested only orally or via print. Consistent with previous findings, early readers, but not pre-readers, accepted printed labels more frequently than when spoken. Children were then presented with identical but unlabelled hybrid exemplars and frequently applied the non-dominant labels to these. Despite early readers' prior greater acceptance of text, when oral suggestions were accepted they retained a greater influence. Findings highlight potential implications for educators regarding knowledge being applied to new scenarios: For early readers, unexpected information from text may be fragile, while a greater confidence might be placed in such information gained from spoken testimony.

Thinking about seeing: perceptual sources of knowledge are encoded in the theory of mind brain regions of sighted and blind adults

Blind people's inferences about how other people see provide a window into fundamental questions about the human capacity to think about one another's thoughts. By working with blind individuals, we can ask both what kinds of representations people form about others' minds, and how much these representations depend on the observer having had similar mental states themselves. Thinking about others' mental states depends on a specific group of brain regions, including the right temporo-parietal junction (RTPJ). We investigated the representations of others' mental states in these brain regions, using multivoxel pattern analyses (MVPA). We found that, first, in the RTPJ of sighted adults, the pattern of neural response distinguished the source of the mental state (did the protagonist see or hear something?) but not the valence (did the protagonist feel good or bad?). Second, these neural representations were preserved in congenitally blind adults. These results suggest that the temporo-parietal junction contains explicit, abstract representations of features of others' mental states, including the perceptual source. The persistence of these representations in congenitally blind adults, who have no first-person experience with sight, provides evidence that these representations emerge even in the absence of relevant first-person perceptual experiences.

The role of culture and language in avoiding misinformation: pilot findings

In two pilot studies, we investigate the possibility that patterns in our linguistic environment affect the likelihood of accepting misinformation. Turkish, which marks its verbs for the source of a speaker's evidence (first-hand perception vs. hearsay), was contrasted with English which does not mark its verbs but which, to signal strength of evidence, must employ optional lexical marking. In the first pilot study, Turkish adults were shown to be affected by that language's obligatory evidential markings: their free recall for details of the events changed as a function of the type of the tense-aspect marker in use, and strong evidential markers led to increased levels of suggestibility when employed with misleading questions. In the second pilot study, Turkish- and English-speaking children were shown to be differentially suggestible depending on combinations of evidential markers in the story presented and the evidential marker employed in the misinformation subsequently provided. Together, these two pilot studies show promise in this area of research, which has been ignored by the forensic community and yet would seem to be relevant when interviewing, taking statements, and giving testimony in cross-linguistic settings.

Take it as read: origins of trust in knowledge gained from print

The ability to read opens up the possibility of learning about the world indirectly via print sources, providing a powerful new opportunity for children who have for years learned effectively from what people tell them. We compared children's trust in printed versus oral information. We also examined whether children who showed preferential trust in an informant with print assumed that the informant was still reliable about new information offered without print support. Children (N=89 aged 3-6 years) received conflicting suggestions from two dolls about which picture showed an unfamiliar target. Only one doll's suggestion referred to a printed label read aloud. Prereaders, despite their exposure to print and presumed experience of others treating print sources as authoritative, showed no clear evidence of preferential trust in the suggestions with print support. Early readers, in contrast, consistently preferred the suggestions with print support. Importantly, despite having treated the doll with print as having a history of accuracy, early readers no longer showed trust in that doll when it subsequently had no print support. Children at the very earliest stages of reading treated the doll with print appropriately as having gained only specific information from the print sources.

How should we question young children's understanding of aspectuality?

In two experiments, we investigated whether 4- to 5-year-old children's ability to demonstrate their understanding of aspectuality was influenced by how the test question was phrased. In Experiment 1, 60 children chose whether to look or feel to gain information about a hidden object (identifiable by sight or touch). Test questions referred either to the perceptual aspect of the hidden object (e.g., whether it was red or blue), the modality dimension (e.g., what colour it was), or the object's identity (e.g., which one it was). Children who heard the identity question performed worse than those who heard the aspect or dimension question. Further investigation in Experiment 2 (N= 23) established that children's difficulty with the identity question was not due to a problem recalling the objects. We discuss how the results of these methodological investigations impact on researchers' assessment of the development of aspectuality understanding.

Beyond semantic accuracy: preschoolers evaluate a speaker's reasons

Children's sensitivity to the quality of epistemic reasons and their selective trust in the more reasonable of 2 informants was investigated in 2 experiments. Three-, 4-, and 5-year-old children (N = 90) were presented with speakers who stated different kinds of evidence for what they believed. Experiment 1 showed that children of all age groups appropriately judged looking, reliable testimony, and inference as better reasons for belief than pretense, guessing, and desiring. Experiment 2 showed that 3- and 4-year-old children preferred to seek and accept new information from a speaker who was previously judged to use the "best" way of thinking. The findings demonstrate that children distinguish certain good from bad reasons and prefer to learn from those who showcased good reasoning in the past.

Developing a concept of choice

Our adult concept of choice is not a simple idea, but rather a complex set of beliefs about the causes of actions. These beliefs are situation-, individual- and culture-dependent, and are thus likely constructed through social learning. This chapter takes a rational constructivist approach to examining the development of a concept of choice in young children. Initially, infants' combine assumptions of rational agency with their capacity for statistical inference to reason about alternative possibilities for, and constraints on, action. Preschoolers' build on this basic understanding by integrating domain-specific causal knowledge of physical, biological, and psychological possibility into their appraisal of their own and others' ability to choose. However, preschoolers continue to view both psychological and social motivations as constraints on choice--for example, stating that one cannot choose to harm another, or to act against personal desires. It is not until later that children share the adult belief that choice mediates between conflicting motivations for action. The chapter concludes by suggesting avenues for future research--to better characterize conceptual changes in beliefs about choice, and to understand how such beliefs arise from children's everyday experiences.

Gaining knowledge via other minds: children's flexible trust in others as sources of information

In five experiments, we examined 3- to 6-year-olds' understanding that they could gain knowledge indirectly from someone who had seen something they had not. Consistent with previous research, children judged that an informant, who had seen inside a box, knew its contents. Similarly, when an informant marked a picture to indicate her suggestion as to the content of the box, 3- to 4-year-olds trusted this more frequently when the informant had seen inside the box than when she had not. Going beyond previous research, 3- to 4-year-olds were also sensitive to informants' relevant experience when they had to look over a barrier to see the marked picture, or ask for the barrier to be raised. Yet when children had to elicit the informant's suggestion, rather than just consult a suggestion already present, even 4- to 5-year-olds were no more likely to do so when the informant had seen the box's content than when she had not, and no more likely to trust the well-informed suggestion than the uninformed one. We conclude that young children who can ask questions may not yet fully understand the process by which they can gain accurate information from someone who has the experience they lack.

Preschoolers can recognize violations of the Gricean maxims

Grice (Syntax and semantics: Speech acts, 1975, pp. 41-58, Vol. 3) proposed that conversation is guided by a spirit of cooperation that involves adherence to several conversational maxims. Three types of maxims were explored in the current study: 1) Quality, to be truthful; 2) Relation, to say only what is relevant to a conversation; and 3) Quantity, to provide as much information as required. Three- to five-year-olds were tested to determine the age at which an awareness of these Gricean maxims emerges. Children requested the help of one of two puppets in finding a hidden sticker. One puppet always adhered to the maxim being tested, while the other always violated it. Consistently choosing the puppet that adhered to the maxim was considered indicative of an understanding of that maxim. The results indicate that children were initially only successful in the Relation condition. While in general, children performed better at first in the Quantity condition compared with the Quality condition, 3-year-olds never performed above chance in the Quantity condition. The findings of the present study indicate that preschool children are sensitive to the violation of the Relation, Quality, and Quantity maxims at least under some conditions.

Believing what you're told: young children's trust in unexpected testimony about the physical world

How do children resolve conflicts between a self-generated belief and what they are told? Four studies investigated the circumstances under which toddlers would trust testimony that conflicted with their expectations about the physical world. Thirty-month-olds believed testimony that conflicted with a naive bias (Study 1), and they also repeatedly trusted testimony that conflicted with an event they had just seen (Study 2)-even when they had an incentive to ignore the testimony (Study 3). Children responded more skeptically if they could see that the testimony was wrong as it was being delivered (Study 3), or if they had the opportunity to accumulate evidence confirming their initial belief before hearing someone contradict it (Study 4). Together, these studies demonstrate that toddlers have a robust bias to trust even surprising testimony, but this trust can be influenced by how much confidence they have in their initial belief.

Was muss man tun, um sicher die richtige Lösung zu finden?

Zusammenfassung. In der vorliegenden Arbeit wird untersucht, welche Wissensquellen GrundschülerInnen für die Lösung von Schulaufgaben in unterschiedlichen Fachkontexten präferieren. Dazu werden in einem experimentellen Design Aufgabenthema („Schwimmen und Sinken”, „Anordnen von Größen” und „Werte bestimmen”) und Fachdisziplin (Mathematik- oder Sachkundeunterricht) als Kontext des Präferenzurteils variiert. Kinder (N = 225) aus der Klassenstufe vier bewerteten für jeweils sechs Schulaufgaben ihre Präferenzen für acht Quellen des Wissens. Die Ergebnisse zeigen in den Präferenzen für Wissensquellen eine systematische Unterscheidung nach Aufgabenthemen und Fachkontexten. Die GrundschülerInnen haben eine klare Vorstellung davon, woher sie am liebsten Informationen bekommen wollen: Grundsätzlich bevorzugen sie für die Informationsgewinnung zur Bearbeitung der schulischen Aufgaben das eigene Handeln (Ausprobieren und Planen des Ausprobierens) und das eigenständige Rechnen im Kontrast zu externen Quellen (z.B. Buch, Lehrer, Internet). Außerdem sind die Präferenzen für externe Quellen im Kontext des Sachkundeunterrichts ausgeprägter als im Mathematikunterricht.

Show or tell: testimony is sufficient to induce the curse of knowledge in three- and four-year-olds

Because much of what children learn extends beyond their first-hand experience, they are reliant upon the testimony of others to acquire information about aspects of the world they have not experienced directly. Here we asked whether testimony alone would be sufficient to induce cognitive biases in knowledge attribution that have been observed when children acquire information through direct observation. A total of 80 three- and four-year-old children were tested on a "curse of knowledge" task to assess their inability to override their own knowledge when asked to assess the knowledge of a nave other. In the present study, we tested children's ability to override knowledge gained through testimony rather than knowledge gained through visual experience. Testimony alone was sufficient to induce the curse of knowledge in three- and four-year-olds. Knowledge obtained through the testimony of others is apparently subject to some of the same cognitive biases that are present when children learn through observation.

Evidentiality and trust: the effect of informational goals

Children's ability to exercise selective trust is crucial for the development of their knowledge and successful socialization. For speakers of some languages, evidentials, which are grammatical source-of-knowledge markers, could provide valuable support of these processes. Focusing on Bulgarian, this chapter situates children's use of evidentials in reliability judgments within the broader context of research on decision making and foregrounds the role of informational goals in children's decisions.

Commentary: what we can learn from research on evidentials

Young children's well-documented difficulty reporting the sources of their knowledge, and their susceptibility to misleading suggestions about what they saw for themselves, might be reduced when their linguistic community expresses knowledge sources with grammatical evidential markers. Alternatively, until children have acquired certain cognitive prerequisites, they may interpret evidentials simply as markers of speakers' certainty. There is evidence supportive of both views, but with more precisely formulated research questions, specially tailored tasks, and more cross-linguistic comparisons, we can come to understand better the developmental intertwining of linguistic, metalinguistic, and cognitive aspects of children's handling of sources of knowledge.

Children's understanding of certainty and evidentiality: advantage of grammaticalized forms over lexical alternatives

In verbal communication, the hearer takes advantage of the linguistic expressions of certainty and evidentiality to assess how committed the speaker might be to the truth of the informational content of the utterance. Little is known, however, about the precise developmental mechanism of this ability. In this chapter, we approach the question by elucidating factors that are likely to constrain young children's understanding of linguistically encoded certainty and evidentiality, including the types of linguistic form of these expressions, namely, grammaticalized or lexical forms.

Knowing how we know: evidentiality and cognitive development

Evidentials are grammatical elements such as affixes and particles indicating the source of knowledge. We provide an overview of this grammatical category and consider three research domains to which developmental studies on evidentiality contribute: the acquisition of linguistic means to characterize knowledge, the conceptual understanding of knowledge sources, and the evaluation of others' testimony. We also consider the study of evidentiality in relation to the Sapir-Whorf hypothesis about the influence of language on thought.