Young children associate novel words with complex objects rather than salient parts.

How do children learn associations between novel words and complex perceptual displays? Using a visual preference procedure, the authors tested 12- and 19-month-olds to see whether the infants would associate a novel word with a complex 2-part object or with either of that object's parts, both of which were potentially objects in their own right and 1 of which was highly salient to infants. At both ages, children's visual fixation times during test were greater to the entire complex object than to the salient part (Experiment 1) or to the less salient part (Experiment 2)--when the original label was requested. Looking times to the objects were equal if a new label was requested or if neutral audio was used during training (Experiment 3). Thus, from 12 months of age, infants associate words with whole objects, even those that could potentially be construed as 2 separate objects and even if 1 of the parts is salient. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of gesture and target on 12- and 18-month-olds' joint visual attention to objects in front of or behind them.

Factors affecting joint visual attention in 12- and 18-month-olds were investigated. In Experiment 1 infants responded to 1 of 3 parental gestures: looking, looking and pointing, or looking, pointing, and verbalizing. Target objects were either identical to or distinctive from distractor objects. Targets were in front of or behind the infant to test G. E. Butterworth's (1991b) hypothesis that 12-month-olds do not follow gaze to objects behind them. Pointing elicited more episodes of joint visual attention than looking alone. Distinctive targets elicited more episodes of joint visual attention than identical targets. Although infants most reliably followed gestures to targets in front of them, even 12-month-olds followed gestures to targets behind them. In Experiment 2 parents were rotated so that the magnitude of their head turns to fixate front and back targets was equivalent. Infants looked more at front than at back targets, but there was also an effect of magnitude of head turn. Infants' relative neglect of back targets is partly due to the "size" of adult's gesture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word learning in the context of referential and salience cues.

Adult referential behavior (gaze direction) and salience (target activation) were independently manipulated in a study of novel word learning. Children (seventy-five 18-month-olds and seventy-two 24-month-olds) were trained in different conditions with a novel word in the context of 2 remote-controlled toys. In response to the novel word at test, 24-month-olds tended to pick out the toy to which the adult referred in all conditions. They also tended to use the novel word appropriately. Comprehension by 18-month-olds was good when the salience of the toy did not conflict with the adult's referential intent, but it was disrupted when referential and salience cues conflicted and when referential cues were not available. Results imply that, at 24 months, children use the referential intent of the speaker to learn new words, but when first learning words, children may have a less secure grasp on the meaning of speakers' referential cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When does and ostrich become a bird? The role of typicality in early word comprehension.

Which objects and animals are children willing to accept as referents for words they know? To answer this question, the authors assessed early word comprehension using the preferential looking task. Children were shown 2 stimuli side by side (a target and a distractor) and heard the target stimulus named. The target stimulus was either a typical or an atypical exemplar of the named category. It was predicted that children first connect typical examples with the target name and broaden the extension of the name as they get older to include less typical examples. Experiment 1 shows that when targets are named, 12-month-olds display an increase in target looking for typical but not atypical targets whereas 24-month-olds display an increase for both. Experiment 2 shows that 18-month-olds display a pattern similar to that of 24-month-olds. Implications for the early development of word comprehension are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Infants’ learning of novel words in a stochastic environment.

In everyday word learning words are only sometimes heard in the presence of their referent, making the acquisition of novel words a particularly challenging task. The current study investigated whether children (18-month-olds who are novice word learners) can track the statistics of co-occurrence between words and objects to learn novel mappings in a stochastic environment. Infants were briefly trained on novel word–novel object pairs with variable degrees of co-occurrence: Words were either paired reliably with 1 referent or stochastically paired with 2 different referents with varying probabilities. Infants were sensitive to the co-occurrence statistics between words and referents, tracking not just the strongest available contingency but also low-frequency information. The statistical strength of the word–referent mapping may also modulate real-time online lexical processing in infants. Infants are thus able to track stochastic relationships between words and referents in the process of learning novel words. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hands in the air: Using ungrounded iconic gestures to teach children conservation of quantity.

Including gesture in instruction facilitates learning. Why? One possibility is that gesture points out objects in the immediate context and thus helps ground the words learners hear in the world they see. Previous work on gesture's role in instruction has used gestures that either point to or trace paths on objects, thus providing support for this hypothesis. The experiments described here investigated the possibility that gesture helps children learn even when it is not produced in relation to an object but is instead produced "in the air." Children were given instruction in Piagetian conservation problems with or without gesture and with or without concrete objects. The results indicate that children given instruction with speech and gesture learned more about conservation than children given instruction with speech alone, whether or not objects were present during instruction. Gesture in instruction can thus help learners learn even when those gestures do not direct attention to visible objects, suggesting that gesture can do more for learners than simply ground arbitrary, symbolic language in the physical, observable world. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Studies in inductive inference in infancy

Imitation of events was used to explore the inductive generalizations that 14-month-olds have made about animals, vehicles, and household artifacts. In Experiment 1 infants generalized domain-specific properties such as drinking to animals but not to vehicles, whereas they generalized domain-neutral properties such as going into a building to exemplars from both domains. The next four experiments showed that infants tend to interpret animal events very broadly, for example, construing a dog merely as a land animal rather than as a differentiated kind in its own right. Infants were somewhat more selective in their construals of vehicles. Experiment 6 showed that 14-month-olds also generalize "basic-level properties" very broadly. For example, they chose a pan to demonstrate drinking almost as often as a cup and fed a bone to a bird as often as to a dog. By 20 months, their selections narrowed appropriately for artifacts, but were still overgeneralized for natural kinds. The experiments indicate that infants tend to generalize their early experiences broadly across domains, often across exemplars that have a variety of different surface characteristics. The data suggest that it is the conceptual meaning of objects, rather than their physical features, that controls early associative learning.     

Linguistic and Conceptual Influences on Adjective Acquisition in 24- and 36-Month-Olds.

Two hundred forty English-speaking toddlers (24- and 36-month-olds) heard novel adjectives applied to familiar objects (Experiment 1) and novel objects (Experiment 2). Children were successful in mapping adjectives to target properties only when information provided by the noun, in conjunction with participants' knowledge of the objects, provided coherent category information: when basic-level nouns or superordinate-level nouns were used with familiar objects, when novel basic-level nouns were used with novel objects, and-for 36-month-olds-when the nouns were underspecified with respect to category (thing or one) but participants could nonetheless infer a category from pragmatic and conceptual knowledge. These results provide evidence concerning how nouns influence adjective learning, and they support the notion that toddlers consider pragmatic factors when learning new words. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of causal models in analogical inference.

Computational models of analogy have assumed that the strength of an inductive inference about the target is based directly on similarity of the analogs and in particular on shared higher order relations. In contrast, work in philosophy of science suggests that analogical inference is also guided by causal models of the source and target. In 3 experiments, the authors explored the possibility that people may use causal models to assess the strength of analogical inferences. Experiments 1-2 showed that reducing analogical overlap by eliminating a shared causal relation (a preventive cause present in the source) from the target increased inductive strength even though it decreased similarity of the analogs. These findings were extended in Experiment 3 to cross-domain analogical inferences based on correspondences between higher order causal relations. Analogical inference appears to be mediated by building and then running a causal model. The implications of the present findings for theories of both analogy and causal inference are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word, thought, and deed: The role of object categories in children's inductive inferences and exploratory play.

Previous research (e.g., S. A. Gelman & E. M. Markman, 1986; A. Gopnik & D. M. Sobel, 2000) suggests that children can use category labels to make inductive inferences about nonobvious causal properties of objects. However, such inductive generalizations can fail to predict objects' causal properties when (a) the property being projected varies within the category, (b) the category is arbitrary (e.g., things smaller than a bread box), or (c) the property being projected is due to an exogenous intervention rather than intrinsic to the object kind. In 4 studies, the authors showed that preschoolers (M = 48 months; range = 42-57 months) were sensitive to these constraints on induction and selectively engaged in exploration when evidence about objects' causal properties conflicted with inductive generalizations from the objects' kind to their causal powers. This suggests that the exploratory actions children generate in free play could support causal learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Integrating language and gesture in infancy.

Whether language/gesture correlations in early language development can be explained by parallelism or comprehension mediation was examined. Study 1, parental report data for 95 1-year olds, suggested that word comprehension and production are dissociated in this age range and that the comprehension and production factors map onto distinct aspects of gesture. Study 2 tested 41 13–15-month-olds in a task in which the modeled gesture was accompanied by supportive, contradictory, or neutral narratives. Results showed that infants can use adult speech as an aid in reproduction of modeled gestures (comprehension mediation). However, there is still additional variance in gestural production that correlates with expressive vocabulary when comprehension-related variance is moved. Thus, comprehension mediation and parallelism both appear to be operating. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Permanent rescue of lesioned neonatal motoneurons and enhanced axonal regeneration by adenovirus-mediated expression of glial cell-line-derived neurotrophic factor

Studies of patients with brain damage suggest that specific brain regions may be differentially involved in representing/processing certain categories of conceptual knowledge. With regard to the dissociation that has received the most attention--between the domains of living things and artifacts--a debate continues as to whether these category-specific effects reflect neural implementation of categories directly or some more basic properties of brain organization. The present positron emission tomography (PET) study addressed this issue by probing explicitly for differential activation associated with written names of objects from the domains of living things or artifacts during similarity judgments about different attributes of these objects. Subjects viewed triads of written object names and selected one of two response words as more similar to a target word according to a specified perceptual attribute (typical color of the objects) or an associative attribute (typical location of the objects). The control task required a similarity judgment about the number of syllables in the target and response words. All tasks were performed under two different stimulus conditions: names of living things and names of artifacts. Judgments for both domains and both attribute types activated an extensive, distributed, left-hemisphere semantic system, but showed some differential activation-particularly as a function of attribute type. The left temporo-occipito-parietal junction showed enhanced activity for judgments about object location, whereas the left anteromedial temporal cortex and caudate nucleus were differentially activated by color judgments. Smaller differences were seen for living and nonliving domains, the positive findings being largely consistent with previous studies using objects; in particular, words denoting artifacts produced enhanced activation in the left posterior middle temporal gyrus. These results suggest that, within a distributed conceptual system activated by words, the more prominent neural distinction relates to type of attribute.     

Stripes do not a zebra make, or do they? Conceptual and perceptual information in inductive inference.

Four-year-olds' and adults' inferences based on shared conceptual properties, category labels, and perceptual information were assessed in 4 experiments. Stimuli included novel animals (Studies 1, 3, and 4) and familiar animals (Study 2). Experiments suggest that both category membership information and similarity (in the form of conceptual information and perceptually provided information) affect inferences. Furthermore, conceptual attribute information and category membership information were used differently by adults but not by children. It is concluded that the inferential behavior of children and adults is influenced by perceptual information, conceptual attribute information, and category membership information, as well as by hypotheses about how these kinds of information relate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acquisition of word–object associations by 14-month-old infants.

The following experiments were designed to determine the age at which infants can first readily learn word–object pairings with only minimal exposure and without social or contextual support. To address this question, 8- to 14-month-old infants were tested on their ability to form word–object associations in a "switch" design. Infants were habituated to 2 word–object pairings and then tested with 1 trial that maintained a familiar word–object pairing and 1 that involved a familiar word and object in a new combination. Across 6 experiments, only 14-month-old infants formed word–object associations under these controlled testing conditions but appeared to do so only when the objects were moving. Although 8- to 12-month-olds did not form the associations, they appeared to process both the word and the object information. These studies provide strong evidence that 14-month-old infants can rapidly learn arbitrary associations between words and objects, that this ability appears to develop at about 14 months of age, and that the Switch design is a useful method for assessing word–object learning in infancy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Causal relations and feature similarity in children's inductive reasoning.

Four experiments examined the development of property induction on the basis of causal relations. In the first 2 studies, 5-year-olds, 8-year-olds, and adults were presented with triads in which a target instance was equally similar to 2 inductive bases but shared a causal antecedent feature with 1 of them. All 3 age groups used causal relations as a basis for property induction, although the proportion of causal inferences increased with age. Subsequent experiments pitted causal relations against featural similarity in induction. It was found that adults and 8-year-olds, but not 5-year-olds, preferred shared causal relations over strong featural similarity as a basis for induction. The implications for models of inductive reasoning and development are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generic language and speaker confidence guide preschoolers’ inferences about novel animate kinds.

We investigated the influence of speaker certainty on 156 four-year-old children’s sensitivity to generic and nongeneric statements. An inductive inference task was implemented, in which a speaker described a nonobvious property of a novel creature using either a generic or a nongeneric statement. The speaker appeared to be confident, neutral, or uncertain about the information being relayed. Preschoolers were subsequently asked if a second exemplar shared the same property as the first. Preschoolers consistently extended properties to additional exemplars only when properties were described in a generic form by a confident or neutral speaker. If a speaker appeared to be uncertain or if statements were made in a nongeneric form, properties were not consistently extended beyond the first exemplar. The findings demonstrate that children integrate the inductive cues provided by generic language with social cues when reasoning about abstract kinds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Infants' association of linguistic labels with causal actions.

Six experiments examined infants' ability to associate nonsense words with 2 causal actions: pushing and pulling. Although Experiment 1 found that 14-month-olds failed to form word-action associations, 18-month-olds in Experiment 2 provided reliable evidence of doing so. Additional experiments explore why 14-month-olds may not have formed such an association. Experiment 3 examined 14-month-old's ability to discriminate a change in either the action or the label when the other element was held constant. Infants discriminated the change in label but not the change in action. When the language labels were replaced with music (Experiments 4–6), 14-month-old infants responded in terms of and discriminated between pushing and pulling. These results, in comparison with those from Experiments 1 and 3, suggest that for 14-month-olds, attempting to associate labels with actions may interfere with their discrimination of similar actions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acquisition of word-object associations by 14-month-old infants

The following experiments were designed to determine the age at which infants can first readily learn word--object pairings with only minimal exposure and without social or contextual support. To address this question, 8- to 14-month-old infants were tested on their ability to form word--object associations in a "switch" design. Infants were habituated to 2 word--object pairings and then tested with 1 trial that maintained a familiar word--object pairing and 1 that involved a familiar word and object in a new combination. Across 6 experiments, only 14-month-old infants formed word--object associations under these controlled testing conditions but appeared to do so only when the objects were moving. Although 8- to 12-month-olds did not form the associations, they appeared to process both the word and the object information. These studies provide strong evidence that 14-month-old infants can rapidly learn arbitrary associations between words and objects, that this ability appears to develop at about 14 months of age, and that the Switch design is a useful method for assessing word--object learning in infancy.     

By land or by sea: The role of perceptual similarity in infants' categorization of animals.

In 3 experiments, the authors used an object-examining task to investigate the role of perceptual similarity in infants' categorization. In Experiment 1, infants were familiarized with a set of either perceptually similar or perceptually variable exemplars from 1 category and tested with novel exemplars from both categories. Ten-month-olds did not respond to the category in either condition, and 13-month-olds responded categorically in both conditions but somewhat differently in the 2 conditions. Experiment 2 showed that when 10-month-olds were familiarized with similar exemplars but not with variable exemplars, they responded to the categorical distinction when given tests with typical exemplars. Experiment 3 established that 10-month-olds could differentiate among the exemplars. These results suggest that the perceptual similarity of the exemplars influences infants' recognition of categorical distinctions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)