Jason Scofield

Two-year-olds differentially disambiguate novel words and facts

When presented with a pair of objects, one familiar and one unfamiliar, and asked to select the referent of a novel word, children reliably demonstrate the disambiguation effect and select the unfamiliar object. The current study investigated two competing word learning accounts of this effect: a pragmatic account and a word learning principles account. Two-, three- and four-year-olds were presented with four disambiguation conditions, a word/word, a word/fact, a fact/word and a fact/fact condition. A pragmatic account predicted disambiguation in all four conditions while a word learning principles account predicted disambiguation in the word/word and fact/word conditions. Results indicated that children disambiguated in word/word and fact/word conditions and two-year-olds disambiguated at above chance levels in the word/word condition but at BELOW chance levels in the fact/fact condition. Because disambiguation varied both as a function of age and condition these findings are presented as challenges to a pragmatic account of the disambiguation effect.

Word learning in the absence of a speaker

Past studies show that a referential context is important for successful word learning. Still in question, however, is the success of word learning in the absence of a referential context. In this study 2-year-olds were presented with novel words in the absence of a speaker and therefore in the absence of a referential context. Findings revealed that word learning was successful across the experimental trials at rates greater than chance and at rates greater than in the control trial. Findings demonstrated that the absence of a speaker and the referential context provided by a speaker did not result in unsuccessful word learning. It is concluded that a referential context is not necessary for successful word learning.

Matters of accuracy and conventionality: prior accuracy guides children's evaluations of others' actions.

Studies show that children trust previously reliable sources over previously unreliable ones (e.g., Koenig, Clément, & Harris, 2004). However, it is unclear from these studies whether children rely on accuracy or conventionality to determine the reliability and, ultimately, the trustworthiness of a particular source. In the current study, 3- and 4-year-olds were asked to endorse and imitate one of two actors performing an unfamiliar action, one actor who was unconventional but successful and one who was conventional but unsuccessful. These data demonstrated that children preferred endorsing and imitating the unconventional but successful actor. Results suggest that when the accuracy and conventionality of a source are put into conflict, children may give priority to accuracy over conventionality when estimating the sources reliability and, ultimately, when deciding who to trust.

Preschool Children's Multimodal Word Learning.

Two studies used a new paradigm to examine preschool childrens (i.e., 2-, 3-, 4-, and 5-year-olds) word learning across multiple sense modalities. In Study 1 (n = 60), children heard a word for an object that they touched but did not see, while word learning was examined using objects that were seen but not touched. In Study 2 (n = 60), children heard a word for an object that they saw but did not touch, while word learning was examined using objects that were touched but not seen. Findings from both studies revealed that children were able to learn words by coordinating information across multiple sense modalities and that word learning improved with age. These findings are discussed in terms of E. J. Gibsons differentiation theory (1969, 1988).

Do 2-year-olds disambiguate and extend words learned from video?

This study investigated whether children learned, disambiguated, and extended words presented via video. Eighteen 2-year-olds saw a series of short videos. Each video depicted a novel target object that was labeled with a novel word. Then the target object was replaced on screen with a pair of objects (which varied by condition) and children were asked to select the object that best matched a novel word. In the baseline and disambiguation conditions, children saw the target and a novel distracter. In the extension condition, children saw an exemplar of the target and a novel distracter. Results showed that children selected the target at above chance levels in the baseline condition and the exemplar at above chance levels in the extension condition. Results also showed that childrens selection in the disambiguation condition did not differ from chance. Possible reasons for childrens inability to disambiguate are discussed.

Clarifying the role of joint attention in early word learning

Four studies examined whether two-year-olds could successfully learn a novel word in conditions in which joint attention was not present. Study 1 examined whether children could learn a novel word while the speaker, but not the child, attended to the target object. Study 2 examined whether children could learn a novel word while the child, but not the speaker, attended to the target object. Study 3 examined whether children could learn a novel word while the child and the speaker attended to two different target objects. Study 4 examined whether children could learn a novel word while neither the child nor the speaker attended to the target object. Findings showed that successful word learning occurred in each of the four studies. These results suggest that joint attention may play an important, though not a necessary, role in young children’s word learning.

Object movement in preschool children's word learning

Two studies examined whether preschool children preferred to select a moving object over stationary objects when determining the referent of a novel word. In both studies three- and four-year-olds observed three novel objects, one moving object and two stationary objects. In Study 1, children (n=44) were asked to select the object that best matched a novel word. In Study 2, children (n=45) were asked to select the object that best matched a novel fact. Results across the two studies indicated that three- and four-year-olds showed a preference for selecting the moving object and that this preference was similar for both words and facts. These results suggest that preschool children are able to use movement to determine the referent of a novel word, especially when other cues are unavailable or unhelpful, but that movement may not be uniquely helpful for word learning.

The effect of a tactile-to-visual shift on young children’s tendency to map novel labels onto novel objects

When taught a label for an object and then asked whether an exemplar of that object or a novel object is the referent of a novel label, children favor the novel object. Preschool-aged children tend not to show this so-called disambiguation effect, however, when the test objects are presented in a different sense modality than the original object. The current experiments used a touch-to-vision paradigm to test two explanations for this unexpected pattern. Experiment 1 asked whether children might fail to retrieve the original label and found that additional label training benefitted 3-year-olds but not 4-year-olds. Experiments 2 and 3 asked whether childrens reaction to discovering the cross-modal match might interfere with how they process the request for the novel label and found that being allowed to share their discovery of the match benefitted 4-year-olds but not 3-year-olds. These findings support the proposal that the chief obstacle to cross-modal disambiguation changes during early childhood from difficulty in retrieving the known label to disruption caused by the discovery of the cross-modal match.

Cued self-awareness and speech fluency

The present study investigated the potential influence of cued attention to self on speaking behavior. Forty-five undergraduate participants completed three tasks: watching a movie clip, telling a story, and completing button-pressing tasks, including a cognitive Stroop-like task. Each task was presented to participants in the presence and absence of video of their own behavior. During each task, indicators of autonomic arousal were acquired, including skin conductance and heart rate. Results showed that autonomic arousal was greater during speaking than movie-watching, and Stroop compared to baseline tasks. The presence of the video resulted in reduced performance, as marked by a greater frequency of speech disfluencies during speaking and increased reaction time during button-pressing tasks. However, the presence of the video was not associated with greater autonomic arousal. Results indicate that cued attention to self can lead to performance decrements, but not increases in autonomic arousal.

The effects of source unreliability on prior and future word learning

Young children regularly learn words from interactions with other speakers, though not all speakers are reliable informants. Interestingly, children will reverse to trusting a reliable speaker when a previously endorsed speaker proves unreliable. When later asked to identify the referent of a novel word, children who reverse trust are less willing to consider previously mislabeled objects. The current studies report two related findings. When later asked to identify the label of a novel object, children who reverse trust are less willing to consider previously misused words. When later asked to identify the referent of a novel word, children who reverse trust are less willing to endorse the testimony of the initially trusted but unreliable speaker – even when judged against a stranger. Overall, these findings suggest reversing trust has residual effects for elements involved in the original acquisition of misinformation (e.g. the mislabeled object, misused word, and originally trusted speaker), and these effects could undermine later word-learning efforts. Accounts of children who continue endorsing an unreliable speaker despite opposing testimony from a reliable speaker are also considered.