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Three- and four-year-old children (N=131) were tested for their sensitivity to the accuracy and inaccuracy of informants. Children were presented with one of three conditions. In the Accurate-Inaccurate condition, one informant named objects accurately whereas the other named them inaccurately. In the Accurate-Neutral condition, one informant named objects accurately whereas the other merely drew attention to them. Finally in the Inaccurate-Neutral condition, one informant named objects inaccurately whereas the other merely drew attention to them. In subsequent test trials, 4-year-olds preferred to seek and accept information in a selective fashion across all three conditions, suggesting that they monitor informants for both accuracy and inaccuracy. By contrast, 3-year-olds were selective in the Accurate-Inaccurate and Inaccurate-Neutral conditions but not in the Accurate-Neutral condition, suggesting that they monitor informants only for inaccuracy and take accuracy for granted. [ABSTRACT FROM AUTHOR]

Given that children do not always trust gossip, do they spontaneously check what they are told? We provided 5- (N = 32) and 6-year olds (N = 32) with gossip concerning characters in a cartoon they were watching, and examined whether they verified the gossip by actively re-watching the relevant episodes. Six-year olds were more likely to verify gossip than 5-year olds. When gossip targeted their favourite characters, children were more likely to verify negative when compared with positive gossip. However, when gossip targeted children's disliked characters, they showed no such valence bias. These results indicate that children's verification of gossip increases with age, and they evaluate claims selectively., (© 2024 British Psychological Society. Published by John Wiley & Sons Ltd.)

The ability to engage in counterfactual thinking (reason about what else could have happened) is critical to learning, agency, and social evaluation. However, not much is known about how individual differences in counterfactual reasoning may play a role in children's social evaluations. In the current study, we investigate how prompting children to engage in counterfactual thinking about positive moral actions impacts children's social evaluations. Eighty-seven 4-8-year-olds were introduced to a character who engaged in a positive moral action (shared a sticker with a friend) and asked about what else the character could have done with the sticker (counterfactual simulation). Children were asked to generate either a high number of counterfactuals (five alternative actions) or a low number of counterfactuals (one alternative action). Children were then asked a series of social evaluation questions contrasting that character with one who did not have a choice and had no alternatives (was told to give away the sticker to his friend). Results show that children who generated selfish counterfactuals were more likely to positively evaluate the character with choice than children who did not generate selfish counterfactuals, suggesting that generating counterfactuals most distant from the chosen action (prosociality) leads children to view prosocial actions more positively. We also found age-related changes: as children got older, regardless of the type of counterfactuals generated, they were more likely to evaluate the character with choice more positively. These results highlight the importance of counterfactual reasoning in the development of moral evaluations. RESEARCH HIGHLIGHTS: Older children were more likely to endorse agents who choose to share over those who do not have a choice. Children who were prompted to generate more counterfactuals were more likely to allocate resources to characters with choice. Children who generated selfish counterfactuals more positively evaluated agents with choice. Comparable to theories suggesting children punish willful transgressors more than accidental transgressors, we propose children also consider free will when making positive moral evaluations., (© 2023 The Authors. Developmental Science published by John Wiley & Sons Ltd.)

What happens when children have formed an impression of a peer based on prior gossip, but later learn from direct observation that the gossip is untrue? We interviewed seventy 5- and 6-year-old children in Zhejiang, China. They first heard conflicting positive and negative gossip about an absent third party, and subsequently learned which piece of gossip was true. Initially, both 5- and 6-year-old children tended to endorse the positive rather than the negative gossip. However, when they learned about the inaccuracy of the positive gossip based on their own direct observation, 6-year-old children subsequently doubted it, whereas 5-year-old children showed no such shift. Taken together, the results show that when children decide what gossip to believe, they are initially swayed by its valence but with age they increasingly weigh gossip in relation to their own direct observation., (© 2023 British Psychological Society.)

There is extensive research on the development of cheating in early childhood but research on how to reduce it is rare. The present preregistered study examined whether telling young children about a story character's emotional reactions towards cheating could significantly reduce their tendency to cheat (N = 400; 199 boys; Age: 3-6 years). Results showed that telling older kindergarten children about the story character's negative emotional reaction towards rule violation significantly reduced cheating, but telling them about the positive emotional reaction towards rule adherence did not. These results show that children as young as age 5 are able to use information about another child's emotional reaction to guide their own moral behavior. In particular, highlighting another child's negative emotional reaction towards a moral transgression may be an effective way to reduce cheating in early childhood. This finding, along with earlier cheating reduction findings, suggests that although cheating is common in early childhood, simple methods can reduce its occurrence., (© 2022 John Wiley & Sons Ltd.)

Five- to 11-year-old U.S. children, from either a religious or secular background, judged whether story events could really happen. There were four different types of stories: magical stories violating ordinary causal regularities; religious stories also violating ordinary causal regularities but via a divine agent; unusual stories not violating ordinary causal regularities but with an improbable event; and realistic stories not violating ordinary causal regularities and with no improbable event. Overall, children were less likely to judge that religious and magical stories could really happen than unusual and realistic stories although religious children were more likely than secular children to judge that religious stories could really happen. Irrespective of background, children frequently invoked causal regularities in justifying their judgments. Thus, in justifying their conclusion that a story could really happen, children often invoked a causal regularity, whereas in justifying their conclusion that a story could not really happen, they often pointed to the violation of causal regularity. Overall, the findings show that children appraise the likelihood of story events actually happening in light of their beliefs about causal regularities. A religious upbringing does not impact the frequency with which children invoke causal regularities in judging what can happen, even if it does impact the type of causal factors that children endorse., (© 2021 Cognitive Science Society LLC.)

In two experiments, 3- to 5-year-old children were tested for their preferences when seeking and accepting information about novel animals. In Experiment 1, children watched as two adults named unfamiliar animals - one adult was predominantly accurate, whereas the other was predominantly inaccurate, as judged by a teacher. In a subsequent test phase, participants viewed additional unfamiliar animals and were invited to endorse one of two conflicting names. Either the predominantly accurate or the predominantly inaccurate adult proposed one name, whereas a majority of three unfamiliar adults proposed the other name. Children were more likely to endorse the predominantly accurate adult as compared to the majority but showed no significant preference for the predominantly inaccurate adult as compared to the majority. In Experiment 2, participants watched two adults correctly name three familiar animals, but only one named three additional unfamiliar animals whereas the other expressed uncertainty. On subsequent test trials, children preferred the apparently well-informed adult to the less-informed adult but, contrary to the results of Experiment 1, children preferred the information provided by a majority instead of the apparently well-informed adult. The implications of these results are discussed in the light of previous research on children's selective trust in an accurate informant as compared to a consensus. Statement of contribution What is already known on the subject? Young children monitor past accuracy and use this epistemic cue to decide whom to trust; Children are receptive to information coming from a consensus; Non-epistemic cues, such as familiarity and accent, also influence children's deference What does this study adds? Children favour a dissenter over a majority if the dissenter's past accuracy has been publicly highlighted. They favour a majority if a dissenter's past accuracy has not been publicly highlighted. A confident informant is preferred to a hesitant informant., (© 2019 The British Psychological Society.)

Recent work has documented that despite preschool-aged children's understanding of social norms surrounding sharing, they fail to share their resources equally in many contexts. Here we explored two hypotheses for this failure: an insufficient motivation hypothesis and an insufficient cognitive resources hypothesis. With respect to the latter, we specifically explored whether children's numerical cognition-their understanding of the cardinal principle-might underpin their abilities to share equally. In Experiment 1, preschoolers' numerical cognition fully mediated age-related changes in children's fair sharing. We found little support for the insufficient motivation hypothesis-children stated that they had shared fairly, and failures in sharing fairly were a reflection of their number knowledge. Numerical cognition did not relate to children's knowledge of the norms of equality (Experiment 2). Results suggest that the knowledge-behavior gap in fairness may be partly explained by the differences in cognitive skills required for conceptual and behavioral equality., (© 2018 John Wiley & Sons Ltd.)

Mounting evidence suggests that endorsement of psychological continuity and the afterlife increases with age. This developmental change raises questions about the cognitive biases, social representations, and cultural input that may support afterlife beliefs. To what extent is there similarity versus diversity across cultures in how people reason about what happens after death? The objective of this study was to compare beliefs about the continuation of biological and psychological functions after death in Tanna, Vanuatu (a Melanesian archipelago), and the United States (Austin, Texas). Children, adolescents, and adults were primed with a story that contained either natural (non-theistic) or supernatural (theistic) cues. Participants were then asked whether or not different biological and psychological processes continue to function after death. We predicted that across cultures individuals would be more likely to endorse the continuation of psychological processes over biological processes (dualism) and that a theistic prime would increase continuation responses regarding both types of process. Results largely supported predictions; U.S. participants provided more continuation responses for psychological than biological processes following both the theistic and non-theistic primes. Participants in Vanuatu, however, provided more continuation responses for biological than psychological processes following the theistic prime. The data provide evidence for both cultural similarity and variability in afterlife beliefs and demonstrate that individuals use both natural and supernatural explanations to interpret the same events., (Copyright © 2016 Cognitive Science Society, Inc.)

Human culture relies on extensive use of social transmission, which must be integrated with independently acquired (i.e. asocial) information for effective decision-making. Formal evolutionary theory predicts that natural selection should favor adaptive learning strategies, including a bias to copy when uncertain, and a bias to disproportionately copy the majority (known as 'conformist transmission'). Although the function and causation of these evolved strategies has been comparatively well studied, little is known of their development. We experimentally investigated the development of the bias to copy-when-uncertain and conformist transmission in children from the ages of 3 to 7, testing predictions derived from theoretical models. Children first attempted to solve a binary-choice quantity discrimination task themselves using asocial information, but were then given the decisions of informants, and an opportunity to revise their answer. We investigated whether children's revised judgments were adaptively contingent on (i) the difficulty of the trial and (ii) the degree of consensus amongst informants. As predicted, older but not younger children copied others more on more difficult trials than on easier trials, even though older children also showed a tendency to stick with their initial, asocial decision. We also found that older children, like adults, were disproportionately receptive to non-total majorities (i.e. were conformist) whereas younger children were receptive only to total (i.e. unanimous) majorities. We conclude that, whilst the mechanism for incorporating social information into decision-making is initially very blunt, across the course of early childhood it converges on the adaptive learning mechanisms observed in adults and predicted by cultural evolutionary theory. A video abstract of this article can be viewed at http://youtu.be/Qb6JINGYqVk., (© 2014 John Wiley & Sons Ltd.)

In two studies, 5- and 6-year-old children were questioned about the status of the protagonist embedded in three different types of stories. In realistic stories that only included ordinary events, all children, irrespective of family background and schooling, claimed that the protagonist was a real person. In religious stories that included ordinarily impossible events brought about by divine intervention, claims about the status of the protagonist varied sharply with exposure to religion. Children who went to church or were enrolled in a parochial school, or both, judged the protagonist in religious stories to be a real person, whereas secular children with no such exposure to religion judged the protagonist in religious stories to be fictional. Children's upbringing was also related to their judgment about the protagonist in fantastical stories that included ordinarily impossible events whether brought about by magic (Study 1) or without reference to magic (Study 2). Secular children were more likely than religious children to judge the protagonist in such fantastical stories to be fictional. The results suggest that exposure to religious ideas has a powerful impact on children's differentiation between reality and fiction, not just for religious stories but also for fantastical stories., (Copyright © 2014 Cognitive Science Society, Inc.)

Kim and Harris (, J. Cogn. Dev.) showed that children selectively learned from an informant who produced apparently magical outcomes as compared to another informant who produced only ordinary outcomes in the domain of everyday physics. In the present study, we tested children's ability to differentiate between and selectively learn from informants who displayed either an extraordinary or an ordinary ability in the domain of everyday psychology. Prior studies have shown that children come to appreciate what is ordinarily involved in knowing the private mental states of other people. Drawing on this research, we asked whether 3- to 4- and 5- to 6-year-old children preferentially learned from an informant who knew another person's mind via either an ordinary or an extraordinary form of communication. As compared to younger children, older children were more likely to learn from the extraordinary informant. Moreover, children's ability to differentiate between the two informants was a better predictor of their learning from the extraordinary informant than age. We discuss the findings in the light of prior work on selective learning, children's ideas about prayer and their understanding of impossibility., (© 2014 The British Psychological Society.)

Children have many opportunities to learn from others through oral and written sources. Recent evidence suggests that early readers place more trust in written over oral testimony when learning names for unfamiliar objects. Across three studies, we examined whether the authority of print extends beyond mere naming to guide children's actions in the physical world. In Study 1, 3- to 6-year-olds received conflicting oral and print-based advice from two puppets about how to operate a novel apparatus. Whereas pre-readers were indiscriminate in their trust, early readers preferred to follow the print-based advice. In Study 2, we replicated this finding, controlling for the amount of corroborating evidence presented by both sources, and the location of the print. In Study 3, we explored whether readers' preference for print-based information was due to a global preference for external representations, or a more specific preference for text. Children were presented with conflicting instructions based on text versus a coloured circle. Whereas pre-readers preferred to follow the colour circle, readers preferred to follow the text. Together, the results suggest that when children learn to read, they rapidly come to regard the written word as a particularly authoritative source of information about how to act in the world., (© 2014 The British Psychological Society.)

The present research investigates how young children evaluate and reason about the disclosure of private information. Using story vignettes, children aged 4-5 and 7-8 years were asked to evaluate an individual who passed on information from a peer revealing that he or she had broken a rule (e.g., stolen a cookie; rule type) or lacked a skill (e.g., could not ride a bicycle; competence type). These negative valence stories were compared with positive valence stories in which the peer had followed a rule or possessed a skill. Younger children approved the sharing of positive, but not negative, information, irrespective of type (rule vs. competence). Older children disapproved the disclosure of someone's incompetence, whereas they approved the disclosure of a rule violation. Children justified their evaluations by reference to social rules in the rule-type vignettes and to an individual's feelings in the competence-type vignettes. The findings suggest that young children are concerned about the disclosure of negative information about other people, but with age they become increasingly concerned about protecting the social order even at the cost of individual privacy., (© 2014 The British Psychological Society.)

Preschool children were presented with slides on a computer screen showing a novel object, together with two informants, one with an attractive and one with a less attractive face. Children were asked which informant they would like to ask about the name of the novel object. After hearing the informants provide conflicting names, they were asked who they thought was correct. Children were more likely to endorse names provided by the person with the more attractive face, a bias that cannot be justified on epistemic grounds. The implications of this finding are discussed., (© 2013 The British Psychological Society.)

Across three studies, we investigated whether 4-year-olds would trust a previously reliable informant when learning novel morphological forms. In Experiment 1, children (N= 16) were presented with two informants: one who correctly named familiar objects and another who named them incorrectly. Children were invited to turn to these informants when learning novel labels and morphological forms. The majority of children chose the previously correct labeller when learning novel label and morphology. In Experiment 2, children (N= 16) were presented with an informant who used familiar plurals correctly and one who used them incorrectly. Children chose the previously correct morphologist when learning novel labels and past tense forms. Thus, children track both semantic and morphological accuracy. In Experiment 3, some children (N= 16) were presented with two informants who differed in naming accuracy, whereas others (N= 16) were presented with two informants who differed in morphological accuracy. To forestall any risk of experimenter cuing, one experimenter blind to the training children had received, tested children with novel labels and morphology. The results replicated those of Experiments 1 and 2. Implications for how children's trust in an informant might play a role in their acquisition of morphological forms are discussed., (©2010 The British Psychological Society.)

Across two experiments, preschool-aged children demonstrated selective learning of non-linguistic information from native-accented rather than foreign-accented speakers. In Experiment 1, children saw videos of a native- and a foreign-accented speaker of English who each spoke for 10 seconds, and then silently demonstrated different functions with novel objects. Children selectively endorsed the silent object function provided by the native-accented speaker. In Experiment 2, children again endorsed the native-accented over the foreign-accented speaker, even though both informants previously spoke only in nonsense speech. Thus, young children demonstrate selective trust in native-accented speakers even when neither informant's speech relays meaningful semantic content, and the information that both informants provide is non-linguistic. We propose that children orient towards members of their native community to guide their early cultural learning., (© 2010 Blackwell Publishing Ltd.)

Previous research suggests that children gradually understand the mitigating effects of apology on damage to a transgressor's reputation. However, little is known about young children's insights into the central emotional implications of apology. In two studies, children ages 4-9 heard stories about moral transgressions in which the wrongdoers either did or did not apologize. In Study 1, children in the no-apology condition showed the classic pattern of 'happy victimizer' attributions by expecting the wrongdoer to feel good about gains won via transgression. By contrast, in the apology condition, children attributed negative feelings to the transgressor and improved feelings to the victim. In Study 2, these effects were found even when the explicit emotion marker 'sorry' was removed from the apology exchange. Thus, young children understand some important emotional functions of apology.

I consider three issues: children's attribution of belief-based emotions, the contribution of language input to children's developing theory of mind, and the default settings we assume in our dealings with the world. I ask whether the proposals made by Mitchell, Currie and Ziegler can help throw light on each issue (Mitchell, Currie, & Ziegler, 2009).

In two experiments, children aged 3, 4 and 5 years (N = 61) were given conflicting information about the names and functions of novel objects by two informants, one a familiar teacher, the other an unfamiliar teacher. On pre-test trials, all three age groups invested more trust in the familiar teacher. They preferred to ask for information and to endorse the information that she supplied. In a subsequent phase, children watched as the two teachers differed in the accuracy with which they named a set of familiar objects. Half the children saw the familiar teacher name the objects accurately and the unfamiliar teacher name them inaccurately. The remaining half saw the reverse arrangement. In post-test trials, the selective trust initially displayed by 3-year-olds was minimally affected by this intervening experience of differential accuracy. By contrast, the selective trust of 4- and 5-year-olds was affected. If the familiar teacher had been the more accurate, selective trust in her was intensified. If, on the other hand, the familiar teacher had been the less accurate, it was undermined, particularly among 5-year-olds. Thus, by 4 years of age, children trust familiar informants but moderate that trust depending on the informants' recent history of accuracy or inaccuracy.

To determine whether children retain a preference for a previously accurate informant only in the short term or for long-term use, 3- and 4-year-old children were tested in two experiments. In both experiments, children were given accuracy information about two informants and were subsequently tested for their selective trust in the two informants (Experiment 1: immediately, 1 day and 1 week later; Experiment 2: immediately, 4 days and 1 week later). Both age groups preferred to trust the accurate informant not only immediately after receiving accuracy information but also at subsequent time-points. Children who were immediately able to explicitly identify the accurate informant were significantly more likely to seek and accept information from her 1 week later. However, even when they had not been asked to explicitly identify the accurate informant both age groups still maintained their preference for her. Thus, by 3 years of age, children spontaneously choose a previously accurate informant up to 1 week after exposure to information regarding her accuracy.

Recent findings show that preschool children are selective with respect to whom they ask for information and whose claims they endorse. In particular, they monitor an informant's record of past accuracy or inaccuracy and use that record to gauge future trustworthiness. We ask if preschoolers also monitor the non-verbal cues of assent or dissent that bystanders display toward an informant's claims and use that information to gauge an informant's trustworthiness. In familiarization trials, 4-year-olds watched as two adult informants made conflicting claims regarding the name of an unfamiliar object. Two adult bystanders consistently signaled assent - via nods and smiles - to the claims of one informant, and dissent - via head shakes and frowns - from the claims of the other informant. When invited to endorse one of the two claims, 4-year-olds mostly agreed with the informant who had received bystander assent. Thus, in the absence of background knowledge about an object's name, children use third-party non-verbal signals to assess the accuracy of conflicting labels. On subsequent test trials, the informants again made conflicting claims about novel object names, but in the absence of the two bystanders. Despite the lack of any informative bystander signals, children with more advanced understanding of mental states continued to display greater trust in the informant who had received bystander assent in the earlier trials.

Across two studies, a wide age range of participants was interviewed about the nature of death. All participants were living in rural Madagascar in a community where ancestral beliefs and practices are widespread. In Study 1, children (8-17 years) and adults (19-71 years) were asked whether bodily and mental processes continue after death. The death in question was presented in the context of a narrative that focused either on the corpse or on the ancestral practices associated with the afterlife. Participants aged 8 years and older claimed that death brings an end to most bodily and mental processes. Nevertheless, particularly in the context of the religious narrative, they claimed that certain mental processes continue even after death. This assertion of an afterlife was more evident among adults than children, especially with respect to cognitive processes, such as knowing and remembering. In Study 2, 5- and 7-year-olds were asked similar questions in connection with the death of a bird and a person. Seven-year-olds consistently claimed that bodily and mental processes cease at death, whereas 5-year-olds were unsystematic in their replies. Together, the two studies replicate and extend findings obtained with Western children showing that, in the course of development, different conceptions of death are elaborated-a biological conception in which death terminates living processes and a religious conception in which death marks the beginning of a new form of spiritual existence., (2008 Cognitive Science Society, Inc.)

Children rely extensively on others' testimony to learn about the world. However, they are not uniformly credulous toward other people. From an early age, children's reliance on testimony is tempered by selective trust in particular informants. Three- and 4-year-olds monitor the accuracy or knowledge of informants, including those that are familiar. They prefer to seek and endorse information provided by someone who has proved accurate in the past rather than someone who has made mistakes or acknowledged ignorance. Future research is likely to pinpoint other heuristics that children use to filter incoming testimony and may reveal more generalized patterns of trust and mistrust among individual children.

In three experiments, children's reliance on other people's testimony as compared to their own, first-hand experience was assessed in the domain of ontology. Children ranging from 4 to 8 years were asked to judge whether five different types of entity exist: real entities (e.g. cats, trees) whose existence is evident to everyone; scientific entities (e.g. germs, oxygen) that are normally invisible but whose existence is generally presupposed in everyday discourse; endorsed beings (e.g. the Tooth Fairy, Santa Claus) whose existence is typically endorsed in discourse with young children; equivocal beings (e.g. monsters, witches) whose existence is not typically endorsed in discourse with young children; and impossible entities (e.g. flying pigs, barking cats) that nobody believes in. Children make a broad dichotomy between entities and beings that they claim to exist (real entities; scientific entities; and endorsed beings) and those whose existence they deny (equivocal beings and impossible entities). They also make a more fine-grained distinction among the invisible entities that they claim to exist. Thus, they assert the existence of scientific entities such as germs with more confidence than that of endorsed beings such as Santa Claus. The findings confirm that children's ontological claims extend beyond their first-hand encounters with instances of a given category. Children readily believe in entities that they cannot see for themselves but have been told about. Their confidence in the existence of those entities appears to vary with the pattern of testimony that they receive.

Oxidative abnormalities precede clinical and pathological manifestations of Alzheimer's disease and are the earliest pathological changes reported in the disease. The olfactory pathways and mucosa also display the pathological features associated with Alzheimer's disease in the brain. Olfactory neurons are unique because they can undergo neurogenesis and are able to be readily maintained in cell culture. In this study, we examined neuronal cell cultures derived from olfactory mucosa of Alzheimer's disease and control patients for oxidative stress responses. Levels of lipid peroxidation (hydroxynonenal), N(epsilon)-(carboxymethyl)lysine (glycoxidative and lipid peroxidation), and oxidative stress response (heme oxygenase-1) were measured immunocytochemically. We found increased levels for all the oxidative stress markers examined in Alzheimer's disease neurons as compared to controls. Interestingly, in one case of Alzheimer's disease, we found hydroxynonenal adducts accumulated in cytoplasmic lysosome-like structures in about 20% of neurons cultured, but not in neurons from control patients. These lysosome-like structures are found in about 100% of the vulnerable neurons in brains of cases of Alzheimer's disease. This study suggests that manifestations of oxidative imbalance in Alzheimer's disease extend to cultured olfactory neurons. Primary culture of human olfactory neurons will be useful in understanding the mechanism of oxidative damage in Alzheimer's disease and can even be utilized in developing therapeutic strategies.

A number of recent findings have demonstrated re-expression of cell cycle-related proteins in vulnerable neurones in Alzheimer's disease. We hypothesize that this attempt by neurones to re-enter mitosis is a response to external growth stimuli that leads to an abortive re-entry into the cell cycle and, ultimately, neuronal degeneration. In this study, to further delineate the role of mitotic processes in the pathogenesis of Alzheimer's disease, we investigated p27, a cyclin-dependent kinase inhibitor that plays a negatively regulatory role in cell cycle progression that, once phosphorylated at Thr187, is degraded via an ubiquitin-proteasome pathway. Here we report that both p27 and phosphorylated p27 (Thr187) show increases in the cytoplasm of vulnerable neuronal populations in Alzheimer's disease vs. age-matched control subjects. Importantly, phosphorylated p27 (Thr187) shows considerable overlap with tau-positive neurofibrillary pathology, including neurofibrillary tangles, dystrophic neurites and neuropil threads. The findings presented here suggest that dysregulation of the cell cycle plays a crucial role in the pathogenesis of Alzheimer's disease that may provide a novel mechanistic basis for therapeutic intervention.