Word learning biases

One way in which children constrain the meaning of novel words is through the whole object assumption. When an adult points to an object and says a word, a child assumes this word labels the entire object, not parts or characteristics of the object. For example, if a child is shown an object and given the label "truck", the child will assume "truck" refers to the entire object instead of the tires, doors, color or other parts. Ellen Markman pioneered work in this field. Her studies suggest that even in cases where color or a dynamic activity is made salient to children, they will still interpret the new word as a label for whole objects. According to cognitive psychologist Elizabeth Spelke, infants' perception of the physical world is guided by three constraints on the behavior of physical objects: objects must move as wholes, objects move independently of each other, and objects move on connected paths. These three constraints help guide children's interpretations of scenes, and, in turn, explains how the whole object bias reflects the non-linguistic status of objects. Domain specificity It is unclear if the word-learning constraints are specific to the domain of language, or if they apply to other cognitive domains. Evidence suggests that the whole object assumption is a result of an object's tangibility; children assume a label refers to a whole object because the object is more salient than its properties or functions. The whole object assumption may reflect non-linguistic levels of an object and exploits the cognitive tendency to analyze the world through a whole object lens, meaning the whole object assumption can be applied to cognitive domains outside of language. Criticisms One criticism of the whole object assumption is that much of the evidence provided is only for children 18 months and older. A more recent study strengthened the breadth of ages and stimuli conditions under which this bias occurs. As early as 12 months, infants can associate words with whole objects when the objects can be viewed as two separate objects and even when one of the parts is made salient. ==Taxonomic assumption==

After a child constrains a novel word to label a whole object, the child must learn how to apply the label to similar objects. Ordinarily, children focus on thematic relations between objects when categorizing. For example, if given soup, children will group it together with a bowl and a spoon. Those items would be thematically related. However, when children are given a new label they shift their attention to taxonomic relationships. What this means for the previous example is instead of soup being related to a bowl or spoon, children relate it to ice cream or pudding. The new label is assumed to refer to other objects within the same taxonomic category. The exact nature of taxonomic assumption is unclear. Baldwin finds that shape is the primary influence of children's expectations towards novel objects. Children draw from a wide variety of characteristics to make inferences, although shape is typically the most prevalent. Ellen Markman's early studies showed this constraint at work. When two- and three-year-olds were presented with two basic-level objects, two different kinds of dogs, and a third thematically related object, dog food, they showed a tendency to select a dog and dog food; however, if one of the dogs was labeled with an unfamiliar word, the children were more likely to select the two dogs. An example of categorical scope and perceptual similarity can be illustrated when children learn animal names. Studies show that children think the identity of an animal only changes if its internal properties change. Children extended labels to two perceptually similar animals more often than when they were dissimilar. Domain specificity The taxonomic assumption is very clearly applicable to cognitive domains outside of language. One obvious domain is children's inductive reasoning. An example of this assumption at work in this domain would be for a child to know that Edgar is a grandfather, and Edgar is bald, so they assume all grandfathers are bald. While there are domains that taxonomic assumptions are seen, there are also clear cognitive domains where these assumptions are avoided, such as identifying causality or classical conditioning. The concept of have perfect accuracy every time with every participant isn't something found in most research, but Nelson claims this assumption might not be biological. Another critique of the taxonomic assumption is that it extends past words thus should not be considered a word learning bias. In 1990, Premack conducted a taxonomic assumption experiment with chimpanzees who were being taught words and those who were not. Premack found similar results of what studies using children found—chimpanzees learning language used the taxonomic assumption. Premack claimed these chimps did not have an idea of real words since they were in the beginning of the word learning process thus making the assumption a nonlinguistic assumption. Others criticize Premack by saying this assumption can fit language but doesn't stop at language which is where the domain specificity comes in. ==Mutual exclusivity assumption==

The whole object assumption leads children to constraining labels to an entire object, but children must also learn labels for characteristics or parts of an object. To override the whole object assumption, children also utilize the mutual exclusivity assumption. Simply put, the mutual exclusivity assumption suggests that every object only has one name. Children resist assigning a label to an object for which they already have a name or at least will not learn the new name as easily. Children are then able to start considering other possibilities for the new label, for instance, a part of the object. For example, an adult presents a child with two objects, a truck and a novel object. The adult asks the child to pick up the blicket. If the child already knows "truck" but has not heard "blicket" as a label for an object, the child will assume this label maps onto the novel object. Markman and Wachtel's 1988 studies demonstrated the learning process through the whole-object and mutual exclusivity assumption. The experimenter told three-year-old children a word and then showed them a picture. She asked whether the label referred to the whole object or a part and outlined each option with her finger. When the whole object was unfamiliar they pointed to the part in only 20% of the trials, but pointed to the part in 57% of the trials when the object was familiar. A recent study attempted to replicate and extend these results. Hansen and Markman taught children a new word for a part of a real object by saying the word and tracing the object's contours. (These gestures were meant to remain as naturalistic as possible). They then asked children to point to the new part in order to identify if they have linked the new name to the intended part. The main manipulation was whether the object was familiar or not. Upholding the mutual exclusivity assumption children pointed to the intended part more often in the familiar object condition. Furthermore, the gesture of pointing/outlining the part itself was insufficient for children to learn the part name. Mutual exclusivity and a gesture were necessary for children to select the novel part. Other researchers have come up with similar principles. Clark's contrast theory holds that "every two forms contrast in meaning". When a new word is presented the child assumes it refers to something that does not yet have a label, but contrast does not take into account the overlap words may have in meaning. Golinkoff's novel name-nameless category (N3C) also states that a child will map a new name to the unnamed object when a named object is present. Unlike contrast, N3C does not require children to understand synonymy, and unlike mutual exclusivity it does not hold that objects have only one name. as well as the acquisition of syntax. Markman and Wachtel (1988) hypothesize that children preference the taxonomic constraint when it interferes with the mutual exclusivity assumption. Merriman and Bowman (1989) found that when children have a specific name for an object, they'd use that name if the object was atypical. The example they use is if a unique car was a "bave," children would not call it a "car." Just like any of the assumptions, it's hard if not impossible to tell where one assumption starts and another stops. ==Noun-category bias ==

The noun-category bias suggests that children learn nouns more quickly than any other syntactic category. It has been found to appear in young children as early as the age of two and is used to help children differentiate between syntactic categories such as nouns and adjectives. Preschool-age children have been found to be inclined to interpret words from just one linguistic category- nouns. Gentner proposes that this might be due to the fact that nouns represent a more concrete object. The noun-category bias places regulations on the possible interpretations that a child might attach to a newly encountered noun. Experiments from Waxman and Gelman as well as Markman and Hutchinson provide results which support the claim that children show preference for categorical relations over random hypothesizing when learning new nouns. This suggests a correlation between language and thought and provides evidence for the theory that syntax and semantics are related. Kauschke and Hofmeister divide the noun-category bias into four separate components: (1) nouns are acquired earlier than verbs and other word classes; (2) nouns form the majority of children’s early vocabularies; (3) nouns in children’s early vocabulary are predominantly object labels; (4) a preference for nouns promotes further language development. Noun-category bias is supported by the translation hypothesis, which finds that children translate new words into something more familiar. A familiar category allows children to translate novel nouns into understandable contexts. The translation hypothesis may be contradicted by research that does not find a correlation between naming and taxonomical choice. ==Shape bias==

The shape bias proposes that children apply names to same-shaped objects. This stems from the idea that children are associative learners that have abstract category knowledge at many different levels. They should be able to identify specifics of each category (e.g. pickles are round, long, green, and bumpy). ==References==