Factors affecting children's graphic symbol use in the third year: Language,similarity, and iconicity

The question addressed in this study is whether the claim that children understand the symbolic status of pictures by the middle of their third year is an overestimate of their ability. Specifically, we asked whether children use language if possible to facilitate their performance in graphic symbolic tasks. Language (availability of verbal labels) was manipulated along with iconicity (degree of resemblance between symbol and referent) and perceptual similarity (between choice items) in a series of four experiments. Children 2.5 and 3 years old were presented with a graphic symbol for 4 s and immediately asked to choose the object depicted (referent) from two choice objects. In Study 1, degree of iconicity between picture and referent was varied and both choice objects had the same verbal label. The 2.5-year-olds failed to use any pictures or replicas as symbols. The 3-year-olds performed well with all types of symbols and better with highly iconic symbols. In Study 2, verbal label availability was manipulated by presenting choice objects having the same or different labels and by varying familiarity of labels. The 2.5-year-olds performed at chance when verbal labels were unavailable but above chance when they were available. The 3-year-olds were above chance in all conditions but performed less well when verbal labels were unavailable. Study 3 confirmed that young children use language to mediate picture symbol use. When 2.5-year-olds were provided with subordinate verbal labels in the matching task, subsequent performance was good even when choice objects had the same basic level verbal label. In Study 4, verbal label availability was contrasted with perceptual similarity between choice objects. When verbal labels could be used and choice objects were dissimilar, performance was best, and when verbal labels could not be used and choice objects were similar, it was worst. The results suggest that children's developing understanding of the symbolic function of pictures is tenuous in the third year, and is supported by their use of verbal labels.     

Mapping language to the world: the role of iconicity in the sign language input

Most research on the mechanisms underlying referential mapping has assumed that learning occurs in ostensive contexts, where label and referent co‐occur, and that form and meaning are linked by arbitrary convention alone. In the present study, we focus on iconicity in language, that is, resemblance relationships between form and meaning, and on non‐ostensive contexts, where label and referent do not co‐occur. We approach the question of language learning from the perspective of the language input. Specifically, we look at child‐directed language (CDL) in British Sign Language (BSL), a language rich in iconicity due to the affordances of the visual modality. We ask whether child‐directed signing exploits iconicity in the language by highlighting the similarity mapping between form and referent. We find that CDL modifications occur more often with iconic signs than with non‐iconic signs. Crucially, for iconic signs, modifications are more frequent in non‐ostensive contexts than in ostensive contexts. Furthermore, we find that pointing dominates in ostensive contexts, and suggest that caregivers adjust the semiotic resources recruited in CDL to context. These findings offer first evidence for a role of iconicity in the language input and suggest that iconicity may be involved in referential mapping and language learning, particularly in non‐ostensive contexts.     

What Is the Buzz About Iconicity? How Iconicity in Caregiver Speech Supports Children's Word Learning

One cue that may facilitate children's word learning is iconicity, or the correspondence between a word's form and meaning. Some have even proposed that iconicity in the early lexicon may serve to help children learn how to learn words, supporting the acquisition of even noniconic, or arbitrary, word–referent associations. However, this proposal remains untested. Here, we investigate the iconicity of caregivers’ speech to young children during a naturalistic free-play session with novel stimuli and ask whether the iconicity of caregivers’ speech facilitates children's learning of the noniconic novel names of those stimuli. Thirty-four 1.5-2-year-olds (19 girls; half monolingual English learners and half bilingual English-Spanish learners) participated in a naturalistic free-play task with their caregivers followed by a test of word-referent retention. We found that caregivers’ use of iconicity, particularly in utterances in which they named the novel stimuli, was associated with the likelihood that children learned that novel name. This result held even when controlling for other factors associated with word learning, such as the concreteness and frequency of words in caregiver speech. Together, the results demonstrate that iconicity not only can serve to help children identify the referent of novel words (as in previous research) but can also support their ability to retain even noniconic word-referent mappings.     

Iconicity and Diachronic Language Change

Iconicity, the resemblance between the form of a word and its meaning, has effects on behavior in both communicative symbol development and language learning experiments. These results have invited speculation about iconicity being a key feature of the origins of language, yet the presence of iconicity in natural languages seems limited. In a diachronic study of language change, we investigated the extent to which iconicity is a stable property of vocabulary, alongside previously investigated psycholinguistic predictors of change. Analyzing 784 English words with data on their historical forms, we found that stable words are higher in iconicity, longer in length, and earlier acquired during development, but that the role of frequency and grammatical category may be less important than previously suggested. Iconicity is revealed as a feature of ultra-conserved words and potentially also as a property of vocabulary early in the history of language origins.     

Toddlers’ joint engagement experience facilitates preschoolers’ acquisition of theory of mind

Forty‐two children participated in a longitudinal study that investigated the relationship between their joint engagement experience when toddlers and their development of theory of mind when preschoolers. Controlling for language comprehension at 30 months, higher preschool false belief scores were associated with more time in coordinated joint engagement earlier (18–21 mo, β= .34) and in symbol‐infused joint engagement later (27–30 mo, β= .35) in toddlerhood. Findings suggest that the early foundation of theory of mind development is laid as toddlers attend to both social‐emotional and symbolic aspects of shared events.     

Iconicity in the speech of children and adults

Iconicity – the correspondence between form and meaning – may help young children learn to use new words. Early‐learned words are higher in iconicity than later learned words. However, it remains unclear what role iconicity may play in actual language use. Here, we ask whether iconicity relates not just to the age at which words are acquired, but also to how frequently children and adults use the words in their speech. If iconicity serves to bootstrap word learning, then we would expect that children should say highly iconic words more frequently than less iconic words, especially early in development. We would also expect adults to use iconic words more often when speaking to children than to other adults. We examined the relationship between frequency and iconicity for approximately 2000 English words. Replicating previous findings, we found that more iconic words are learned earlier. Moreover, we found that more iconic words tend to be used more by younger children, and adults use more iconic words when speaking to children than to other adults. Together, our results show that young children not only learn words rated high in iconicity earlier than words low in iconicity, but they also produce these words more frequently in conversation – a pattern that is reciprocated by adults when speaking with children. Thus, the earliest conversations of children are relatively higher in iconicity, suggesting that this iconicity scaffolds the production and comprehension of spoken language during early development.     

Symbolic functioning in preschool children

An important goal of parents and preschool educators alike is to introduce young children to a variety of symbol systems, and to help children begin to master some of these crucial cultural tools. Our research indicates that, in spite of the importance that adults place on symbolization, adult intuitions about the acquisition of symbolic functioning and how to facilitate it are often poor. In this article we summarize research on toddlers' understanding of two kinds of symbols—models and pictures. We show that the initial insight that something is a symbol or representation of something else is extremely challenging for young children, and it is an insight that must be achieved with each symbol system they encounter. Two factors that contribute to the difficulty children have appreciating symbolic relations are discussed: dual representation (the ability to think about something in two different ways at the same time; specifically, the ability to think of something both as an object itself and a symbol for something else) and representational specificity (understanding that a symbol can stand for a specific reality). Implications of these factors for preschool practice are considered.     

Transfer between Picture Books and the Real World by Very Young Children

Picture book reading is a very common form of interaction between parents and very young children. Here we explore to what extent young children transfer novel information between picture books and the real world. We report that 15- and 18-month-olds can extend newly learned labels both from pictures to objects and from objects to pictures. However, the degree to which they do so is affected by iconicity—how much the objects and pictures resemble one another. The children in these studies more often extended the labels between picture and object when realistic photographs and drawings were involved than less realistic cartoons. These results show that higher levels of perceptual similarity between symbol and referent make the referential relation more transparent, thereby helping children transfer information between them. Thus, the educational function of early picture book interactions may best be served with realistic illustrations.     

The effect of iconicity of visual displays on statistical reasoning: evidence in favor of the null hypothesis

Knowing which properties of visual displays facilitate statistical reasoning bears practical and theoretical implications. Therefore, we studied the effect of one property of visual diplays?– iconicity (i.e., the resemblance of a visual sign to its referent)?– on Bayesian reasoning. Two main accounts of statistical reasoning predict different effect of iconicity on Bayesian reasoning. The ecological-rationality account predicts a positive iconicity effect, because more highly iconic signs resemble more individuated objects, which tap better into an evolutionary-designed frequency-coding mechanism that, in turn, facilitates Bayesian reasoning. The nested-sets account predicts a null iconicity effect, because iconicity does not affect the salience of a nested-sets structure—the factor facilitating Bayesian reasoning processed by a general reasoning mechanism. In two well-powered experiments (N = 577), we found no support for a positive iconicity effect across different iconicity levels that were manipulated in different visual displays (meta-analytical overall effect: log OR = ?0.13, 95 % CI [?0.53, 0.28]). A Bayes factor analysis provided strong evidence in favor of the null hypothesis—the null iconicity effect. Thus, these findings corroborate the nested-sets rather than the ecological-rationality account of statistical reasoning.     

Predictors of early person reference development: Maternal language input,attachment and neurodevelopmental markers

In a longitudinal natural language development study in Germany, the acquisition of verbal symbols for present persons, absent persons, inanimate things and the mother–toddler dyad was investigated. Following the notion that verbal referent use is more developed in ostensive contexts, symbolic play situations were coded for verbal person reference by means of noun and pronoun use. Depending on attachment classifications at twelve months of age, effects of attachment classification and maternal language input were studied up to 36 months in four time points. Hierarchical regression analyses revealed that, except for mother absence, maternal verbal referent input rates at 17 and 36 months were stronger predictors for all referent types than any of the attachment organizations, or any other social or biological predictor variable. Attachment effects accounted for up to 9.8% of unique variance proportions in the person reference variables. Perinatal and familial measures predicted person references dependent on reference type. The results of this investigation indicate that mother-reference, self-reference and thing-reference develop in similar quantities measured from the 17-month time point, but are dependent of attachment quality.     

The role of perseveration in children's symbolic understanding and skill

In the first few years of life, children become increasingly sensitive to the significance of a variety of symbolic artifacts. An extensive body of research has explored very young children's ability to use symbol‐based information as a guide to current reality. In one common task, for example, children watch as a miniature toy is hidden in a scale model, and are then asked to retrieve a larger version of the toy from the corresponding place in the room itself. Two‐and‐a‐half‐year‐old children perform very poorly in most versions of this task. Their most common error is to perseverate; that is, they search again at the location where the toy was last hidden. Two studies examined the degree to which 2¹/₂‐year‐olds’ high rate of perseveration and poor performance stem from problems with inhibitory control. Results showed that problems with inhibitory control contribute very little to 2¹/₂‐year‐old children's difficulty with the task. Instead, the results confirm young children's great difficulty appreciating and exploiting symbol–referent relations.     

No evidence for infants’ contingency detection as a precursor of toddlers’ self-recognition

The aim of the present study was to assess the relationship between infants’ contingency preference and detection in the first year of life and toddlers’ mirror and video self-recognition in the second and third year of life in a longitudinal study (N = 113). Six- and 9-month-olds’ preference for a noncontingent over a perfect contingent view (contingency preference) and their differentiation between the two views – indicated by longer looking times to either view – (contingency detection) were assessed in two contingency tasks. A mirror-face-recognition task and a mirror-leg-recognition task were conducted at 18 months. A video-face-recognition task and a mirror-leg-recognition task were conducted at 26 months. Results revealed no predictive relationships between infants’ contingency preference and detection in the first year of life and their ability to recognize themselves in a mirror or on a video monitor in the second and third year of life. This finding supports the notion that self-recognition emerges independently from the experience of contingencies (Bischof-Köhler, 1991, 2012). Thus, a representation of the self seems to rely on more than a specific developmental pathway leading from contingency preference and detection to self-recognition.     

Domestic dogs comprehend human communication with iconic signs

A key skill in early human development is the ability to comprehend communicative intentions as expressed in both nonlinguistic gestures and language. In the current studies, we confronted domestic dogs (some of whom knew many human ‘words’) with a task in which they had to infer the intended referent of a human's communicative act via iconic signs – specifically, replicas and photographs. Both trained and untrained dogs successfully used iconic replicas to fetch the desired item, with many doing so from the first trial. Dogs’ ability to use photographs in this same situation was less consistent. Because simple matching to sample in experimental contexts typically takes hundreds of trials (and because similarity between iconic sign and target item did not predict success), we propose that dogs’ skillful performance in the current task reflects important aspects of the comprehension of human communicative intentions.     

Becoming a high‐fidelity – super – imitator: what are the contributions of social and individual learning?

In contrast to other primates, human children's imitation performance goes from low to high fidelity soon after infancy. Are such changes associated with the development of other forms of learning? We addressed this question by testing 215 children (26–59 months) on two social conditions (imitation, emulation) – involving a demonstration – and two asocial conditions (trial‐and‐error, recall) – involving individual learning – using two touchscreen tasks. The tasks required responding to either three different pictures in a specific picture order (Cognitive: Airplane→Ball→Cow) or three identical pictures in a specific spatial order (Motor‐Spatial: Up→Down→Right). There were age‐related improvements across all conditions and imitation, emulation and recall performance were significantly better than trial‐and‐error learning. Generalized linear models demonstrated that motor‐spatial imitation fidelity was associated with age and motor‐spatial emulation performance, but cognitive imitation fidelity was only associated with age. While this study provides evidence for multiple imitation mechanisms, the development of one of those mechanisms – motor‐spatial imitation – may be bootstrapped by the development of another social learning skill – motor‐spatial emulation. Together, these findings provide important clues about the development of imitation, which is arguably a distinctive feature of the human species.     

Spontaneous pointing by bottlenose dolphins (Tursiops truncatus)

Two bottlenose dolphins (Tursiops truncatus) participating in a symbolic communication project spontaneously developed behaviors that resembled pointing and gaze alternation. The dolphins' behavior demonstrated several features reminiscent of referential communicative behavior. It was triadic, involving a signaler, receiver, and referent. It was also indicative, specifying a focus of attention. The dolphins' points were distinct from the act of attending to or acting on objects. Spontaneous dolphin pointing was influenced by the presence of a potential receiver, and the distance between that receiver and the dolphin. These findings suggest that dolphins are capable of producing referential gestures. Accepted after revision: 14 August 2001 Electronic Publication     

How do young children’s spatio-symbolic skills change over short time scales?

Three experiments were designed to examine how experience affects young children's spatio-symbolic skills over short time scales. Spatio-symbolic reasoning refers to the ability to interpret and use spatial relations, such as those encountered on a map, to solve symbolic tasks. We designed three tasks in which the featural and spatial correspondences between a map and its referent (a model) were systematically manipulated using a map-model paradigm. We explored how 2.5- to 5-year-olds learn to map spatial arrays when both identical and unique correspondences coexist (Experiment 1), when featural cues are absent (Experiment 2), and when object and location similarities are contradictory, thereby making both featural and spatial mapping strategies distinct (Experiment 3). Although younger children have a stronger tendency to focus on object (or featural) cues, even 2.5-year-olds can appreciate a symbol beyond the level of object similarity. With age, children are increasingly capable of learning to use spatio-relational mapping and of discovering a spatio-symbolic mapping strategy to solve more challenging map use tasks over short time scales.     

Children with autism are impaired in the understanding of teaching

Children learn novel information using various methods, and one of the most common is human pedagogical communication or teaching – the purposeful imparting of information from one person to another. Neuro‐typically developing (TD) children gain the ability to recognize and understand teaching as a core method for acquiring knowledge from others. However, it is not known when children with Autism Spectrum Disorder (ASD) acquire the ability to recognize and understand teaching. This study (total N = 70) examined whether children with ASD recognize the two central elements that define teaching: (1) that teaching is an intentional activity; and (2) that teaching requires a knowledge difference between teacher and learner. Theory of mind understanding was also tested. Compared to individually matched TD children, high cognitively functioning children with ASD were impaired in their comprehension of both components of teaching understanding, and their performance was correlated with theory of mind understanding. These findings could have broad implications for explaining learning in children with autism, and could help in designing more effective interventions, which could ultimately lead to improved learning outcomes for everyday life skills, school performance, health, and overall well‐being.     

Two‐year‐olds’ understanding of self‐symbols

This study investigated 48 2.5‐year‐olds’ ability to map from their own body to a two‐dimensional self‐representation and also examined relations between parents’ talk about body representations and their children's understanding of self‐symbols. Children participated in two dual‐representation tasks in which they were asked to match body parts between a symbol and its referent. In one task, they used a self‐symbol and in the other they used a symbol for a doll. Participants were also read a book about body parts by a parent. As a group, children found the self‐symbol task more difficult than the doll‐task; however, those whose parents explicitly pointed out the relation between their children's bodies and the symbols in the book performed better on the self‐symbol task. The findings demonstrate that 2‐year‐old children have difficulty comprehending a self‐symbol, even when it is two‐dimensional and approximately the same size as them, and suggest that parents’ talk about self‐symbols may facilitate their understanding.