Does Iconicity Matter? Deaf and Hearing Preschoolers' Sensitivity to Symbols' Form-Meaning Similarities

Iconicity, the relationship between a symbol’s form and its meaning, is an inherent part of sign languages, as both signs’ referents and signs themselves exist in physical space. Adult learners of sign languages are able to take advantage of iconicity. This paper explores whether preschoolers are sensitive to the iconicity of signs and use form-meaning mappings in language learning like adults. Experiment 1 tested the ability of 87 hearing children, ages 3 to 5 years, to recognize the iconicity of signs that describe the shape of objects. Experiment 2 assessed 82 hearing 3to 5-year-olds’ memory for iconic and arbitrary signs to see whether children take advantage of the similarities between iconic signs and their referents to learn new signs. Experiment 3 considered the same abilities in 27 deaf children learning American Sign Language (ASL) to explore whether the modality of the language one is acquiring affects iconicity recognition and use. Children recognized iconic signs with familiar referents as well as those with unfamiliar referents, implying that previous experience with a referent does not mediate recognition of iconicity. Hearing and deaf 4and 5-year-olds reliably recognized iconicity (p = .001), while 3year-olds recognized iconic signs only at chance (ps > .05). Accordingly, hearing 4and 5-yearolds benefitted from iconicity in a fast-mapping task, and learned iconic signs better than arbitrary ones (p = .015), and older deaf children showed a similar patter in their sign learning (p = .07). Children seemed to recognize perceptually iconic signs that describe shape later in development than function iconic signs that mimic how to use an object, and perform equivalently when signs’ referents are familiar or novel objects. Despite iconicity’s prevalence in sign languages but not spoken languages, preschoolers’ use of iconicity does not depend on the modality of the language they are acquiring. UNDERSTANDING OF ICONICITY 5 UNDERSTANDING OF ICONICITY 6 Does Iconicity Matter? Deaf and Hearing Preschoolers’ Sensitivity to Symbols’ Form-Meaning Similarities During the preschool years, children must tackle the task of learning countless new words. For most children, this process happens automatically, by actively attending to the language used in their environment and by making inferences about words’ meanings based on context (Carey, 1977) and syntax (e.g. Arunachalam & Waxman, 2010). Children use context and syntax to determine a word’s meaning from the form of the word when the form is completely arbitrary as is the case with most spoken word, but what process do children use during learning when the form of a symbol is related to its meaning? The current study investigates 3to 5-year-olds’ ability to recognize and remember a symbol’s meaning when there is a transparent relationship between the symbol’s form and meaning. Iconic symbols, such as the onomatopoeic English word boom, share features with the concepts they describe. In other words, the phonology of boom recreates the sounds it represents. Four-year-olds learning Japanese, a language with substantial onomatopoeia, can generalize the principles of onomatopoeia to understand the meanings of both known and novel onomatopoetic words (Haryu, 2010). In general, spoken languages afford limited opportunities for iconicity, because vocal symbols are emitted using sound waves and therefore can only iconically describe sound-related representations. The visual-manual modality of sign languages and gesture lends itself well to iconicity, as objects, signs, and gestures all exist in the same perceptual, in this case physical, space (Bosworth & Emmorey, 2010). For example, the sign TREE in American Sign Language (ASL) is iconic in its depiction of the object’s shape, with the forearm held upright to represent the tree’s trunk and the hand spread open to represent the tree's branches (see Figure 1). UNDERSTANDING OF ICONICITY 7 Figure 1. The forearm in the iconic ASL sign TREE maps onto the tree’s trunk and the fingers map onto the tree’s branches. Similarly, gestures are iconic when the form, and movement, of the hands relates to the semantic content of a speaker’s message. If there are two baskets displayed in a shop window, a customer might make an iconic gesture to clarify which basket he is interested in purchasing (see Figure 2). In this way, iconic gestures supplement information in speech and can clarify meaning (McNeill, 1985). UNDERSTANDING OF ICONICITY 8 Figure 2. The speaker uses an iconic gesture to describe the shape of the basket (a). Iconicity can take many forms (for a review see Bellugi & Klima, 1976, and Taub, 2001). The current study investigates children’s understanding of perceptually iconic gestures and signs for objects, where the hands and arms describe the referent’s shape, as seen in the ASL sign TREE and the gesture for the basket described above (see Figures 1 and 2), as opposed to iconic signs or gestures that employ pantomime, where the signer mimics a behavior associated with an object or action. Symbolic Gesture Children’s spontaneous production of iconic gestures provides compelling evidence for children’s ability to understand symbol-referent connections, because if children can produce an iconic symbol, they may have an implicit understanding of how symbols and referents relate. UNDERSTANDING OF ICONICITY 9 Infants develop both gestural and verbal symbols at roughly the same time in development, yet a statistically insignificant time lag exists between the first production of symbolic gesture and the first production of symbolic word. This lag might exist because gestures are initially easier for children to articulate, but the development of memory and certain requisite cognitive skills need to be attained before children can produce any kind of symbol (Goodwyn & Acredolo, 1993). Together with the maturation of articulators, reaching these cognitive milestones determines when children will start to use symbolic gesture. Children begin to produce iconic gestures during their second year, but these gestures are most commonly enactments rather than descriptions of objects’ shapes or features like those often produced by adults (Acredolo & Goodwyn, 1988). At 18 months, toddlers interpret gestures as symbols, but at 26 months, they prefer to accept spoken words as symbols. However, after a training period where the 26-month-olds were taught and encouraged to use gestures, they accepted gestures as symbols, implying that children begin life without a bias toward spokenlanguage symbols, but later form a bias as they begin to combine multiple spoken words (Namy & Waxman, 1998). While children, including preschoolers, produce iconic gestures (Boyatzis & Watson, 1993), their understanding of the iconic relationship between a gesture and its referent may be weak. In their gesture production, children may be modeling their caregivers and not exhibiting a deep understanding of iconicity. This paper explores children’s ability to recognize the connections between iconic signs and their referents to determine whether preschool-age children are explicitly aware of inherent symbol-referent relationships. Analogical Reasoning: Overcoming the Dual Representation Problem An iconic symbol is analogical in that information about the referent is embedded in the symbol’s form. Studying children’s appreciation of models as stand-ins for real-world objects UNDERSTANDING OF ICONICITY 10 provides us with a basis for how children interpret symbols, and addresses whether children are sensitive to the analogical relationship between a symbol and its meaning. The model-object connection (i.e., understanding that a toy car is a model for a larger functional car) is not always easy for children to grasp and develops with age. By 18 months, children have a fragile comprehension of the toy-real exemplar relationship, but show a solid understanding of this connection by 26 months (Younger & Johnson, 2004). Increasing the similarities between the model and the real-world object improves children’s understanding of their relationship. For example, preschoolers are better able to find a hidden toy in a matching room when the setups of the rooms are similar in terms of furniture as well as similar in terms of size, and older children understand the significance of models better than younger children (DeLoache, Peralta de Mendoza, & Anderson, 1999). Children depend on similarity, or iconicity, to make the mapping between two similar setups. The scale models in these experiments were both real-world objects themselves as well as symbols. The reason younger children struggle with this task could be that they have difficulty constructing dual representations for the model— the room as a scale-model and the room as its own object (DeLoache, Kolstad, & Anderson, 1991). Iconic signs might be challenging for children to interpret, as they are not only symbols but also are distinct entities themselves, just like models are both objects themselves as well as symbols. Perhaps once a child has sufficient experience with symbolic materials— either models or gestures— the child can master the dual representation problem and appreciate symbol-referent relations (DeLoache, Peralta de Mendoza, & Anderson, 1999). UNDERSTANDING OF ICONICITY 11 Children’s Developing Ability to Interpret Iconicity The ability to recognize iconicity develops during early childhood, and the type of iconicity, method of labeling, as well as children’s experience with referents likely affect this ability. Eighteen-month-olds and 4-year-olds can map both arbitrary gestures, such as touching one’s index fingers together to mean bunny, as well as iconic gestures, onto familiar objects, while 26-month-olds only map iconic function gestures (Namy, Campbell, & Tomasello, 2004). The changing nature of children’s sensitivity to iconic gestures suggests that an intriguing pattern unfolds during development. Whi