Children's working understanding of knowledge sources: Confidence in knowledge gained from testimony

In three experiments, children aged between 3 and 5 years (N = 38, 52, 94; mean ages 3–7 to 5–2) indicated their confidence in their knowledge of the identity of a hidden toy. With the exception of some 3-year-olds, children revealed working understanding of their knowledge source by showing high confidence when they had seen or felt the toy, and lower confidence when they had been told its identity by an apparently well-informed speaker. Correct explicit source reports were not necessary for children to show relative uncertainty when the speaker subsequently doubted the adequacy of his access to the toy. After a 2-min delay, 3–4-year-olds, unlike 4–5-year-olds, failed to see the implications of the speaker's doubt about his access.     

Children's understanding of human and super-natural mind

Barrett, Richert, and Driesenga [Barrett, J. L., Richert, R. A., & Driesenga, A. (2001). God's beliefs versus mother's: The development of nonhuman agents concepts. Child Development, 72(1), 50–65] have suggested that children are able to conceptualize the representational properties held by certain super-natural entities, such as God, before they achieve representational understanding of the human mind. The two experimental conditions of the present study aimed at cross-checking the above suggestion. One hundred and twenty children aged from 3 to 7 years were involved in both conditions. In the first, a modified perspective-taking and appearance-reality task, similar to that adopted in Barrett et al.'s study, was used. The task in the second addressed another aspect of representational understanding of the human mind, that is, the early emerging of the rule that knowledge is constrained by perception. The results of the study showed that younger children systematically treat God as a human protagonist regarding the representational properties they possess. Moreover, it was found that children are able to reason, accurately, about God's representational properties, only upon reaching their 5th year of age, when their representational understanding of the human mind becomes stable and robust.     

Effects of stimulus duration and inter-letter spacing on letter-in-string identification

Effects of stimulus duration and inter-letter spacing were studied in a letter-in-string identification paradigm. Participants were shown strings of 5 random consonants (e.g., PGKDM) centered on fixation and were asked to identify the letter that had appeared at a post-cued location. Stimulus duration was manipulated in Experiment 1 (13 ms–91 ms), and inter-letter spacing manipulated in Experiment 2 (for a fixed stimulus duration of 26 ms). We contrasted performance to outer-letters (positions 1 and 5) with non-central inner letters (positions 2 and 4), the first-letter (position 1) with the final letter (position 5), and the central-letter (position 3) with the other inner letters (positions 2 and 4). The outer-letter advantage and the first-letter advantage were present throughout the entire range of exposure durations, whereas the central-letter advantage increased with longer exposures. On the other hand, increased spacing reduced both the outer-letter advantage and the first-letter advantage, whereas it led to a greater central-letter advantage. Changes in acuity and crowding as a function of stimulus exposure and inter-letter spacing, can account for this pattern of results.     

Visual experiences during letter production contribute to the development of the neural systems supporting letter perception

Letter production through handwriting creates visual experiences that may be important for the development of visual letter perception. We sought to better understand the neural responses to different visual percepts created during handwriting at different levels of experience. Three groups of participants, younger children, older children, and adults, ranging in age from 4.5 to 22 years old, were presented with dynamic and static presentations of their own handwritten letters, static presentations of an age‐matched control's handwritten letters, and typeface letters during fMRI. First, data from each group were analyzed through a series of contrasts designed to highlight neural systems that were most sensitive to each visual experience in each age group. We found that younger children recruited ventral‐temporal cortex during perception and this response was associated with the variability present in handwritten forms. Older children and adults also recruited ventral‐temporal cortex; this response, however, was significant for typed letter forms but not variability. The adult response to typed letters was more distributed than in the children, including ventral‐temporal, parietal, and frontal motor cortices. The adult response was also significant for one's own handwritten letters in left parietal cortex. Second, we compared responses among age groups. Compared to older children, younger children demonstrated a greater fusiform response associated with handwritten form variability. When compared to adults, younger children demonstrated a greater response to this variability in left parietal cortex. Our results suggest that the visual perception of the variability present in handwritten forms that occurs during handwriting may contribute to developmental changes in the neural systems that support letter perception.     

Parent-administered computer-assisted tutoring targeting letter-sound knowledge: Evaluation via multiple-baseline across three preschool students

Knowledge of letters sounds has been identified as a primary objective of preschool instruction and intervention. Despite this designation, large disparities exist in the number of letter sounds children know at school entry. Enhancing caregivers' ability to teach their preschool-aged children letter sounds may represent an effective practice for reducing this variability and ensuring that more children are prepared to experience early school success. This study used a non-concurrent multiple-baseline-across-participants design to evaluate the effectiveness of caregivers (N = 3) delivering a computer-assisted tutoring program (Tutoring Buddy) targeting letter sound knowledge to their preschool-aged children. Visual analyses and effect size estimates derived from Percentage of All Non-Overlapping Data (PAND) statistics indicated consistent results for letter sound acquisition, as 6 weeks of intervention yielded large effects for letter sound knowledge (LSK) across all three children. Large effect sizes were also found for letter sound fluency (LSF) and nonsense word fluency (NWF) for two children. All three caregivers rated the intervention as highly usable and were able to administer it with high levels of fidelity. Taken together, the results of the present study found Tutoring Buddy to be an effective, simple, and usable way for the caregivers to support their children's literacy development.     

Muslim Discrimination: Evidence From Two Lost‐Letter Experiments

Since the 9/11 terrorist attacks, there has been considerable concern about whether Muslims living in Western countries are targets of prejudice. A considerable amount of survey‐based evidence suggests that Muslims are victims of discrimination. This paper tested this hypothesis. Two lost‐letter experiments were conducted to test whether the difference in returned letters would be attributable to whether the addressee was Muslim or Swedish. The results show that Muslims receive far fewer letters than do Swedes. However, this discrimination only appears when the lost letters contain money; in which case, the finder gains by not posting the letter.     

Supporting children’s counterfactual thinking with alternative modes of responding

To speculate about counterfactual worlds, children need to ignore what they know to be true about the real world. Prior studies yielding individual differences data suggested that counterfactual thinking may be related to overcoming prepotent responses. In two experiments, we manipulated how 3- to 5-year-olds responded to counterfactual conditional and syllogism tasks. In Experiment 1 (N = 39), children’s performance improved on both conditional and syllogism tasks when they responded with an arrow rather than pointing with a finger. In Experiment 2 (N = 42), 3- and 4-year-olds benefited from both an arrow manipulation and, separately, the introduction of a delay before responding. We suggest that both manipulations help children to overcome an impulsive prepotent response to counterfactual questions arising from a default assumption that information about the past is true.     

Knowing How to Project Objects: Probing the Generality of Children's Action Knowledge

Previous work on the development of intuitive knowledge about trajectories has shown a dissociation between young children's aimed throwing actions, in which they are highly sensitive to the physical laws of motion, and their explicit judgments, in which they exhibit misconceptions. This research investigated the generality of children's action knowledge by having the participants project a ball with a sling. Instead of adjusting sling stretch, and hence sling force, correctly as a function of both the release height and the target distance, 5- and 6-year-olds (Experiment 1, N = 32) and, without flight feedback, even most 7- to 10-year-olds (Experiment 2, N = 96) considered distance only and ignored the height dimension. Similarly, children's judgments of the required sling stretch tended to follow a distance-only rule, especially with children younger than 9 years of age. These results show that young children's action knowledge exhibited in throwing does not generalize to arbitrary means of force production. They further suggest that there is no developmental trend toward such generalization in the age range examined.     

Deontic and epistemic reasoning in children

It is widely accepted that adults show an advantage for deontic over epistemic reasoning. Two published studies (Cummins, 1996b; Harris and Núñez, 1996, Experiment 4) found evidence of this “deontic advantage” in preschool-aged children and are frequently cited as evidence that preschoolers show the same deontic advantage as adults. However, neither study has been replicated, and it is not clear from either study that preschoolers were showing the deontic advantage under the same conditions as adults. The current research investigated these issues. Experiment 1 attempted to replicate both Cummins’s and Harris and Núñez’s studies with 3- and 4-year-olds (N = 56), replicating the former with 4-year-olds and the latter with both 3- and 4-year-olds. Experiment 2 modified Cummins’s task to remove the contextual differences between conditions, making it more similar to adult tasks, finding that 4-year-olds (n = 16) show no evidence of the deontic advantage when no authority figure is present in the deontic condition, whereas both 7-year-olds (n = 16) and adults (n = 28) do. Experiment 3 removed the authority figure from the deontic condition in Harris and Núñez’s task, again finding that 3- and 4-year-olds (N = 28) show no evidence of the deontic advantage under these conditions. These results suggest that for preschoolers, the deontic advantage is reliant on particular contextual cues such as the presence of an authority figure, in the deontic condition. By 7 years of age, however, children are reasoning like adults and show evidence of the advantage when no such contextual cues are present.     

Développement de la connaissance des lettres capitales. Étude transversale chez les enfants français de trois à six ans

The present study examined the knowledge of uppercase letters in 160 children aged from three to six. Three tasks were administrated: letter saying, letter naming, letter recognition. Children's responses were analyzed according to several variables: school level, gender, task, letter type, letter frequency, etc. Letter knowledge improved from three to six years, but with huge differences among children, namely the superiority of girls over boys. Letter by letter analyses showed that scores were highly consistent between tasks and school levels. They also revealed that letter knowledge was affected by letter type, letter frequency, alphabetic rank and the presence of letters in the child's first name. The findings are discussed for their contribution to the understanding of letter learning.     

Compact representations of positional knowledge in short and long words for letters and features

Single-letter statistical measures providing values for each letter-position and word-length combination are too unwieldy for use in working letter-recognition models; more compact tables are needed. Compact tables collapsing word length to short or long words and letter positions to first, last, or middle letters are presented for the frequency and versatility of single letters. Letter-position and word-size differences are preserved in this reduced format. To test awareness of these values, subjects rate the commonness of letters in each letter position. Their responses indicate high intersubject agreement and correlate highly with the frequency and versatility measures. A LISP program that translates the letter knowledge for each letter into a corresponding knowledge for each feature in a feature set is described. Distinctiveness values for each feature (see Shimron & Navon, 1981) are computed.     

Conflicting desire and the child's theory of mind

We contrast the standard representational theory-of-mind approach to the understanding of mental states with an alternative view that theory-of-mind tasks require executive functioning or the inhibition of more “cognitively salient” information. Two experiments test the hypothesis that 3-year-olds' apparent problems on theory-of-mind tasks are not due to an inability to represent the mental contents of another, but rather lie in the informational structure of the task. In Experiment 1, 3- to 5-year-olds were tested on their understanding of desire in others either when they themselves held a strong and conflicting desire or when they had no strong desire. Results showed that under the condition of having a strong and conflicting desire, only 5-year-olds were able to recognize that another person may desire something different. In contrast, when the children themselves held no strong desire, even 3-year-olds were able to judge another's desire correctly. Experiment 2 compared 3-year-olds' performance on a standard false-belief task with an equivalently structured desire task in which participants had again to inhibit their own strong and conflicting desire. Results showed similar performance on the traditional false-belief task and the new conflicting-desire task.     

An infrared system for the detection of a pigeon''s pecks at alphanumeric characters on a TV screen: the dependency of letter detection on the predictability of one letter by another.

Three pigeons pecked at letters of the alphabet and at the symbol "?" displayed on a computer-driven cathode ray screen. A 4 by 4 matrix of infrared emitting and detecting diodes and associated circuitry identified the location of a pigeon''s responses to the screen. Responses at the target letter T were probabilistically reinforced with food whenever T appeared in a string of three letters in the middle of the screen. Responses at the symbol "?" appearing below this string were probabilistically reinforced whenever T did not appear. The letter F anywhere in the three-character string either strongly predicted the occurrence of the target letter T, in two conditions, or predicted its nonoccurrence, in a third. This manipulation of the frequency with which the familiar letter F predicted T was shown to change the function relating probability of a correct peck at the symbol "?" to the number of Fs in the string. This effect may be interpreted as an instance of the phenomenon where an organism''s acquired knowledge changes what it sees.     

Relations Among Early Object Recognition Skills: Objects and Letters

Human visual object recognition is multifaceted and comprised of several domains of expertise. Developmental relations between young children's letter recognition and their 3-dimensional object recognition abilities are implicated on several grounds but have received little research attention. Here, we ask how preschoolers' success in recognizing letters relates to their ability to recognize 3-dimensional objects from sparse shape information alone. Seventy-three 2 1/2 to 5-year-old children completed a “Letter Recognition” task, measuring the ability to identify a named letter among 3 letters, and a “Shape Caricature Recognition” task, measuring recognition of familiar objects from sparse, abstract information about their part shapes and the spatial relations among those parts. Children also completed a control “Shape Bias” task, in which success depends on matching exact shapes but not on building an internal representation of the configuration of features characteristic of an object category or letter. Children's success in letter recognition was positively related to their shape caricature recognition scores, but not to their shape bias scores. The results suggest that letter recognition builds upon developing skills in attending to and representing the relational structure of object shape, and that these skills are common to both 2-dimensional and 3-dimensional object perception.     

Are all letters really processed equally and in parallel? Further evidence of a robust first letter advantage

This present study examined accuracy and response latency of letter processing as a function of position within a horizontal array. In a series of 4 Experiments, target-strings were briefly (33 ms for Experiments 1 to 3, 83 ms for Experiment 4) displayed and both forward and backward masked. Participants then made a two alternative forced choice. The two alternative responses differed just in one element of the string, and position of mismatch was systematically manipulated. In Experiment 1, words of different lengths (from 3 to 6 letters) were presented in separate blocks. Across different lengths, there was a robust advantage in performance when the alternative response was different for the letter occurring at the first position, compared to when the difference occurred at any other position. Experiment 2 replicated this finding with the same materials used in Experiment 1, but with words of different lengths randomly intermixed within blocks. Experiment 3 provided evidence of the first position advantage with legal nonwords and strings of consonants, but did not provide any first position advantage for non-alphabetic symbols. The lack of a first position advantage for symbols was replicated in Experiment 4, where target-strings were displayed for a longer duration (83 ms). Taken together these results suggest that the first position advantage is a phenomenon that occurs specifically and selectively for letters, independent of lexical constraints. We argue that the results are consistent with models that assume a processing advantage for coding letters in the first position, and are inconsistent with the commonly held assumption in visual word recognition models that letters are equally processed in parallel independent of letter position.     

Breaking the reading code: Letter knowledge when children break the reading code the first year in school

The aim of this study was to examine when children learn to read and how learning to read depends on a foundation of alphabetic knowledge. 356 children aged 5–6 years completed assessments of letter-sound knowledge, i.e. the names and sounds of uppercase and lowercase letters of the Norwegian alphabet. Each child was tested at the start, the middle and the end of the school year. The time that each child broke the reading code was also recorded. The results indicated that 11% of the children knew how to read before starting school and 27% of the children did not learn to read by the end of the first year. The remaining children typically knew 21 uppercase letter sounds before they were first able to read, and only a few (<5%) knew less than 11 uppercase letter sounds when they broke the reading code. The average of all four letter-scores at the time they broke the reading code was 19 ± 5 letters (mean ± standard deviation). Although letter sound knowledge was associated with the ability to read, it was not sufficient for breaking the reading code. 40% of children who knew 23 letter sounds or more, enough to read more than 80% of the most common Norwegian words, and 15% of children who knew all 29 letter sounds still could not read. Based on these data, it seems reasonable to advocate learning letter-sound correspondences early in the first year of school to form the best possible basis for breaking the reading code.     

How do use and comprehension of mental-state language relate to theory of mind in middle childhood?

This study investigates the relationship between mental-state language and theory of mind in primary school children. The participants were 110 primary school students (mean age = 9 years and 7 months; SD = 12.7 months). They were evenly divided by gender and belonged to two age groups (8- and 10-year-olds). Linguistic, metacognitive and cognitive measures were used to assess the following competencies: verbal ability, use of mental-state terms, understanding of metacognitive language, understanding of second-order false beliefs, and emotion comprehension. Correlations between children’ use of mental-state language and their performance on theory-of-mind tasks were moderate, whereas correlations between children's comprehension of such language and ToM abilities were high. In addition, regression analyses showed that comprehension of metacognitive language was the variable which best explained children's performance on both false belief tasks and an emotion comprehension test when verbal ability and age were controlled for.     

Preschoolers’ understanding of multiple orientations to reality: The adjectives task

Preschoolers’ understanding that an object can be accurately described using two different non-synonymous words was investigated using a task in which children (N = 36) had to judge which of two animals had provided correct adjectival labels for a series of pictures. For some pictures, only one animal provided a correct adjective, for some both animals were correct, and for some neither was correct. For all types of judgement, 4-year-olds outperformed 3-year-olds. Children in both age groups performed worst on trials where both animals were correct. Children's performance on the adjectives task related to concurrent understanding of the appearance–reality distinction, but not to false-belief task performance. Implications for children's mentalizing development are discussed.