Preschoolers’ appreciation of speaker vocal affect as a cue to referential intent

An eye tracking methodology was used to evaluate 3- and 4-year-old children’s sensitivity to speaker affect when resolving referential ambiguity. Children were presented with pictures of three objects on a screen (including two referents of the same kind, e.g., an intact doll and a broken doll, and one distracter item), paired with a prerecorded referentially ambiguous instruction (e.g., “Look at the doll”). The intonation of the instruction varied in terms of the speaker’s vocal affect: positive-sounding, negative-sounding, or neutral. Analyses of eye gaze patterns indicated that 4-year-olds, but not 3-year-olds, were more likely to look to the referent whose state matched the speaker’s vocal affect as the noun was heard (e.g., looked more often to the broken doll referent in the negative affect condition). These findings indicate that 4-year-olds can use speaker affect to help identify referential mappings during on-line comprehension.     

Pragmatics aid referent disambiguation and word learning in young children and adults

How do children succeed in learning a word? Research has shown robustly that, in ambiguous labeling situations, young children assume novel labels to refer to unfamiliar rather than familiar objects. However, ongoing debates center on the underlying mechanism: Is this behavior based on lexical constraints, guided by pragmatic reasoning, or simply driven by children's attraction to novelty? Additionally, recent research has questioned whether children's disambiguation leads to long-term learning or rather indicates an attentional shift in the moment of the conversation. Thus, we conducted a pre-registered online study with 2- and 3-year-olds and adults. Participants were presented with unknown objects as potential referents for a novel word. Across conditions, we manipulated whether the only difference between both objects was their relative novelty to the participant or whether, in addition, participants were provided with pragmatic information that indicated which object the speaker referred to. We tested participants’ immediate referent selection and their retention after 5 min. Results revealed that when given common ground information both age groups inferred the correct referent with high success and enhanced behavioral certainty. Without this information, object novelty alone did not guide their selection. After 5 min, adults remembered their previous selections above chance in both conditions, while children only showed reliable learning in the pragmatic condition. The pattern of results indicates how pragmatics may aid referent disambiguation and learning in both adults and young children. From early ontogeny on, children's social-cognitive understanding may guide their communicative interactions and support their language acquisition.

Research Highlights

• We tested how 2-3-year-olds and adults resolve referential ambiguity without any lexical cues.
• In the pragmatic context both age groups disambiguated novel word-object-mappings, while object novelty alone did not guide their referent selection.
• In the pragmatic context, children also showed increased certainty in disambiguation and retained new word-object-mappings over time.
• These findings contribute to the ongoing debate on whether children learn words on the basis of domain-specific constraints, lower-level associative mechanisms, or pragmatic inferences.

     

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.     

Toddlers use speech disfluencies to predict speakers' referential intentions

The ability to infer the referential intentions of speakers is a crucial part of learning a language. Previous research has uncovered various contextual and social cues that children may use to do this. Here we provide the first evidence that children also use speech disfluencies to infer speaker intention. Disfluencies (e.g. filled pauses 'uh' and 'um') occur in predictable locations, such as before infrequent or discourse-new words. We conducted an eye-tracking study to investigate whether young children can make use of this distributional information in order to predict a speaker's intended referent. Our results reveal that young children (ages 2;4 to 2;8) reliably attend to speech disfluencies early in lexical development and are able to use disfluencies in online comprehension to infer speaker intention in advance of object labeling. Our results from two groups of younger children (ages 1;8 to 2;2 and 1;4 to 1;8) suggest that this ability emerges around age 2.     

The principles of conventionality and contrast in word learning: an empirical examination

In Study 1, 4-year-olds avoided 2 names for an object when exposed to a common or a proper noun in a puppet's presence or to a common noun in a puppet's absence, but not when exposed to a proper noun in a puppet's absence. In Study 2, 3-year-olds avoided 2 names for an object when the requester for the referent of a second label in a different language was bilingual and present during naming, but not when the speaker was bilingual but absent or monolingual. Study 3 followed up on the results of the first 2 studies. When children could assume that the puppet knew the name the experimenter used, they inferred that the puppet's use of a different name implied a different referential intent.     

Turning Believers into Skeptics: 3-Year-Olds' Sensitivity to Cues to Speaker Credibility

Under most circumstances, children (and adults) can safely assume that the testimony they hear is true. In two studies, we investigated whether 3-year-olds (N = 100) would continue to hold this assumption even if the person who provided the testimony behaved in an uncertain, ignorant, and/or distracted manner. In Study 1, children were less likely to trust that, for example, a key-like object was a spoon if the speaker indicated uncertainty about her testimony (e.g., “I think this is a spoon”) than if she simply labeled the object ostensively (e.g., “This is a spoon”). In Study 2, 3-year-olds were also more skeptical about a speaker's testimony when she had earlier made an obvious naming error and seemed distracted, but not when she either made an error or seemed distracted. These results indicate that 3-year-olds can respond differently to the same testimony, depending on the speaker's behavior.     

Thee,uhh disfluency effect in preschoolers: A cue to discourse status

Speech disfluencies, such as filled pauses (ummm, uhhh), are increasingly recognized as an informative element of the speech stream. Here, we examined whether 2‐ and 3‐year‐olds expected that the presence of filled pause would signal reference to objects that are new to a discourse. Children viewed pairs of familiar objects on a screen and heard a speaker refer to one of the objects twice in succession. Next, children heard a critical utterance and were asked to look and point at either the discourse‐given (i.e., previously mentioned) or discourse‐new (i.e., previously unmentioned) object using a fluent (‘Look at the ball!’) or disfluent (‘Look at thee uh ball!’) expression. The results indicated that 3‐year‐old children, but not 2‐year‐old children, initially expected the speaker to continue to refer to given information in the critical utterance. Upon hearing a filled pause, however, both 2‐ and 3‐year‐old children's looking patterns reflected increased looks to discourse‐new objects, although the timing of the effect differed between the age groups. Together, these findings demonstrate that young children have an emerging understanding of the role of filled pauses in speech.     

Young Children's Sensitivity to Speaker Gender When Learning From Others

This research explores whether young children are sensitive to speaker gender when learning novel information from others. Four- and 6-year-olds (N = 144) chose between conflicting statements from a male versus a female speaker (Studies 1 and 3) or decided which speaker (male or female) they would ask (Study 2) when learning about the functions of novel objects. Some objects were in gender-typing colors (light pink or navy blue), and some were in a gender-ambiguous color (yellow). The results indicated that children did use speaker gender to guide their learning, by either consistently choosing to agree with the speakers of their own gender or making choices that are associated with gender stereotypes about color. The findings are discussed in relation to how in-group preference and stereotype attributions might influence children's learning from others.     

Perception and presupposition in real-time language comprehension: insights from anticipatory processing

Recent studies have shown that listeners use verbs and other predicate terms to anticipate reference to semantic entities during real-time language comprehension. This process involves evaluating the denoted action against relevant properties of potential referents. The current study explored whether action-relevant properties are readily available to comprehension systems as a result of the embodied nature of linguistic and conceptual representations. In three experiments, eye movements were monitored as listeners followed instructions to move depicted objects on a computer screen. Critical instructions contained the verb return (e.g., Now return the block to area 3), which presupposes the previous displacement of its complement object--a property that is not reflected in perceptible or stable characteristics of objects. Experiment 1 demonstrated that predictions for previously displaced objects are generated upon hearing return, ruling out the possibility that anticipatory effects draw directly on static affordances in perceptual symbols. Experiment 2 used a referential communication task to evaluate how communicative relevance constrains the use of perceptually derived information. Results showed that listeners anticipate previously displaced objects as candidates upon hearing return only when their displacement was known to the speaker. Experiment 3 showed that the outcome of the original act of displacement further modulates referential predictions. The results show that the use of perceptually grounded information in language interpretation is subject to communicative constraints, even when language denotes physical actions performed on concrete objects.     

Sensitivity to spacing changes in faces and nonface objects in preschool-aged children and adults

Sensitivity to variations in the spacing of features in faces and a class of nonface objects (i.e., frontal images of cars) was tested in 3- and 4-year-old children and adults using a delayed or simultaneous two-alternative forced choice matching-to-sample task. In the adults, detection of spacing information was robust against exemplar differences for faces but varied across exemplars for cars (Experiment 1A). The 4-year-olds performed above chance in both face and car discrimination even when differences in spacing were very small (within ±1.6 standard deviations [SDs]) and the task involved memory components (Experiment 1B), and the same was true for the 3-year-olds when tested with larger spacing changes (within ±2.5 SDs) in a task that posed no memory demands (Experiment 2). An advantage in the discrimination of faces over cars was found at 4 years of age, but only when spacing cues were made more readily available (within ±2.5 SDs). Results demonstrate that the ability to discriminate objects based on feature spacing (i.e., sensitivity to second-order information) is present at 3 years of age and becomes more pronounced for faces than cars by 4 years of age.     

Tone of voice guides word learning in informative referential contexts

Listeners infer which object in a visual scene a speaker refers to from the systematic variation of the speaker's tone of voice (ToV). We examined whether ToV also guides word learning. During exposure, participants heard novel adjectives (e.g., “daxen”) spoken with a ToV representing hot, cold, strong, weak, big, or small while viewing picture pairs representing the meaning of the adjective and its antonym (e.g., elephant–ant for big–small). Eye fixations were recorded to monitor referent detection and learning. During test, participants heard the adjectives spoken with a neutral ToV, while selecting referents from familiar and unfamiliar picture pairs. Participants were able to learn the adjectives' meanings, and, even in the absence of informative ToV, generalize them to new referents. A second experiment addressed whether ToV provides sufficient information to infer the adjectival meaning or needs to operate within a referential context providing information about the relevant semantic dimension. Participants who saw printed versions of the novel words during exposure performed at chance during test. ToV, in conjunction with the referential context, thus serves as a cue to word meaning. ToV establishes relations between labels and referents for listeners to exploit in word learning.     

Toddlers’ referential understanding of pictures

Pictures are referential in that they can represent objects in the real world. Here we explore the emergence of understanding of the referential potential of pictures during the second year of life. In Study 1, 15-, 18-, and 24-month-olds learned a word for a picture of a novel object (e.g., “blicket”) in the context of a picture book interaction. Later they were presented with the picture of a blicket along with the real object it depicted and asked to indicate the blicket. Many of the 24-, 18-, and even 15-month-olds indicated the real object as an instance of a blicket, consistent with an understanding of the referential relation between pictures and objects. In Study 2, children were tested with an exemplar object that differed in color from the depicted object to determine whether they would extend the label they had learned for the depicted object to a slightly different category member. The 15-, 18-, and 24-month-old participants failed to make a consistent referential response. The results are discussed in terms of whether pictorial understanding at this age is associative or symbolic.     

2.5-year-olds use cross-situational consistency to learn verbs under referential uncertainty

Recent evidence shows that children can use cross-situational statistics to learn new object labels under referential ambiguity (e.g., Smith & Yu, 2008). Such evidence has been interpreted as support for proposals that statistical information about word-referent co-occurrence plays a powerful role in word learning. But object labels represent only a fraction of the vocabulary children acquire, and arguably represent the simplest case of word learning based on observations of world scenes. Here we extended the study of cross-situational word learning to a new segment of the vocabulary, action verbs, to permit a stronger test of the role of statistical information in word learning. In two experiments, on each trial 2.5-year-olds encountered two novel intransitive (e.g., "She's pimming!"; Experiment 1) or transitive verbs (e.g., "She's pimming her toy!"; Experiment 2) while viewing two action events. The consistency with which each verb accompanied each action provided the only source of information about the intended referent of each verb. The 2.5-year-olds used cross-situational consistency in verb learning, but also showed significant limits on their ability to do so as the sentences and scenes became slightly more complex. These findings help to define the role of cross-situational observation in word learning.     

Early understanding of age- and environment-related noxiousness in biological kinds: Evidence for a naive theory

Four experiments evaluated whether children have a naive theory in which biological kinds, specifically foods, are distinguished by potential for decomposition. In the first two experiments, 4- through 6-year-olds judged that natural changes such as aging make biological natural kinds (BNK; e.g., apple) noxious, but do not have a comparable effect on nonbiological natural kinds (e.g., rock) or artifacts. In Experiment 3, few children were able to articulate specific biological mechanisms responsible for perceptible signs of noxiousness. But most children in Experiment 4 exhibited the more general understanding that the processes by which BNK become noxious are irreversible. In sum, young children seem to have a domain-specific theory of biological kinds, although they are unaware of the exact mechanisms operative in the domain. Children may thus develop a theory that picks out a domain of objects before the causal principles organizing this domain are fully understood.     

Preschool children's use of cues to generic meaning

Sentences that refer to categories - generic sentences (e.g., "Dogs are friendly") - are frequent in speech addressed to young children and constitute an important means of knowledge transmission. However, detecting generic meaning may be challenging for young children, since it requires attention to a multitude of morphosyntactic, semantic, and pragmatic cues. The first three experiments tested whether 3- and 4-year-olds use (a) the immediate linguistic context, (b) their previous knowledge, and (c) the social context to determine whether an utterance with ambiguous scope (e.g., "They are afraid of mice", spoken while pointing to 2 birds) is generic. Four-year-olds were able to take advantage of all the cues provided, but 3-year-olds were sensitive only to the first two. In Experiment 4, we tested the relative strength of linguistic-context cues and previous-knowledge cues by putting them in conflict; in this task, 4-year-olds, but not 3-year-olds, preferred to base their interpretations on the explicit noun phrase cues from the linguistic context. These studies indicate that, from early on, children can use contextual and semantic information to construe sentences as generic, thus taking advantage of the category knowledge conveyed in these sentences.     

The Growth of Flexible Problem Solving: Preschool Children Use Changing Verbal Cues to Infer Multiple Word Meanings

Flexible induction is the adaptation of probabilistic inferences to changing problems. Young children's flexibility was tested in a word-learning task. Children 3 to 6 years old were told 3 novel words for each of several novel objects. Children generalized each word to other objects with the same body shape, the same material, or the same part as the first object. Each word was preceded by a different predicate (i.e., "looks like a ...," "is made of ...," or "has a ...") that implies a different attribute (shape, material, or part, respectively). Three-year-olds showed limited use of predicates to infer word meanings, and they used predicates from previous trials to infer the meanings of later words. 4- to 6-year-olds used predicate cues more consistently and made inferences that were implied by the most recent predicate cue. Notably, 3-year-olds performed near ceiling in a control task that eliminated the need to use probabilistic inductive cues (Experiment 3). The results suggest that flexibility develops as a function of (a) sensitivity to between-problem variability and indeterminacy and (b) ability to decontextualize the most recent verbal cue to guide of inductive inferences.     

Consistency between verbal and non-verbal affective cues: a clue to speaker credibility

Listeners are exposed to inconsistencies in communication; for example, when speakers’ words (i.e. verbal) are discrepant with their demonstrated emotions (i.e. non-verbal). Such inconsistencies introduce ambiguity, which may render a speaker to be a less credible source of information. Two experiments examined whether children make credibility discriminations based on the consistency of speakers’ affect cues. In Experiment 1, school-age children (7- to 8-year-olds) preferred to solicit information from consistent speakers (e.g. those who provided a negative statement with negative affect), over novel speakers, to a greater extent than they preferred to solicit information from inconsistent speakers (e.g. those who provided a negative statement with positive affect) over novel speakers. Preschoolers (4- to 5-year-olds) did not demonstrate this preference. Experiment 2 showed that school-age children's ratings of speakers were influenced by speakers’ affect consistency when the attribute being judged was related to information acquisition (speakers’ believability, “weird” speech), but not general characteristics (speakers’ friendliness, likeability). Together, findings suggest that school-age children are sensitive to, and use, the congruency of affect cues to determine whether individuals are credible sources of information.     

Young Bilingual Children's Heightened Sensitivity to Referential Cues

Children growing up in a dual-language environment have to constantly monitor the dynamic communicative context to determine what the speaker is trying to say and how to respond appropriately. Such self-generated efforts to monitor speakers' communicative needs may heighten children's sensitivity to, and allow them to make better use of, referential gestures to figure out a speaker's referential intent. In a series of studies, we explored monolingual and bilingual preschoolers' use of nonverbal referential gestures such as pointing and gaze direction to figure out a speaker's intent to refer. In Study 1, we found that 3- and 4-year-old bilingual children were better able than monolingual children to use referential gestures (e.g., gaze direction) to locate a hidden toy in the face of conflicting body-distal information (the experimenter was seated behind an empty box while the cue was directed at the correct box). Study 2 found that by 5 years of age, monolingual children had mastered this task. Study 3 established that the bilingual advantage can be found in children as young as 2 years old. Thus, the experience of growing up in a bilingual environment fosters the development of the understanding of referential intent.     

Is perseveration caused by inhibition failure? Evidence from preschool children's inferences about word meanings

Four studies examined the relation between children's cognitive inhibition and flexibility in a lexical inference task. Children's linguistic flexibility was assessed by the Flexible Induction of Meaning (FIM) test (Deák, 2000a), which requires that children shift inferences about the meanings of several words for novel objects. In Study 1, 54 3-year-olds either were trained between blocks of problems, for a delay of 3 min, or received no training or delay. Training delays did not influence perseveration. In Study 2 (N=72 3- and 4-year-olds') novel word problems were grouped either to increase the frequency of cue switches (i.e., reduce response "set") or minimize the interval between problems about the same objects. Again, no effect was found. In Study 3, 48 3- and 4-year-olds completed 6 preliminary trials; in a high interference group these trials generated a response set to be inhibited upon the first switch to a new cue context. This group did not perseverate more than a control group. There was no association between FIM perseveration and a Stroop-like test of verbal inhibition though both were marginally related to receptive vocabulary. In study 4 (48 3- and 4-year-olds), FIM was again unrelated to Stroop performance, but was related to the ability to tell whether a situation or problem is indeterminate. Thus, flexibility across semantic inferences is not influenced by timing, order, and number of pre-switch problems and is not predicted by individual differences in a test of verbal inhibition. However previously reported age and individual differences in flexible induction of word meanings are robust and related to vocabulary and logical ability.