Ups and Downs in Auditory Development: Preschoolers' Sensitivity to Pitch Contour and Timbre

Connecting the tots: Strong looking-pointing correlations in preschoolers' word learning and implications for continuity in language development

How does one assess developmental change when the measures themselves change with development? Most developmental studies of word learning use either looking (infants) or pointing (preschoolers and older). With little empirical evidence of the relationship between the two measures, developmental change is difficult to assess. This paper analyzes 914 pointing, looking children (451 female, varied ethnicities, 2.5-6.5 years, dates: 2009-2019) in 36 word- or sound-learning experiments with two-alternative test trials. Looking proportions and pointing accuracy correlated strongly (r = .7). Counter to the "looks first" hypothesis, looks were not sensitive to incipient knowledge that pointing missed: when pointing is at chance, looking proportions are also. Results suggest one possible path forward for assessing continuous developmental change. Methodological best practices are discussed.

Preschoolers Have Difficulty Discriminating Novel Minimal-Pair Words

PURPOSE

The primary aim was to assess whether children have difficulty distinguishing similar-sounding novel words. The secondary aim was to assess what task characteristics might hinder or facilitate perceptual discrimination.

METHOD

Three within-subjects experiments tested ninety-nine 3- to 5-year-old children total. Experiment 1 presented two cartoon characters each saying a novel word. Children were asked to report whether they said the same word or different words. Words were identical (e.g., deev/deev), were dissimilar (deev/vush), differed in onset consonant voicing (deev/teev), or differed in vowel tenseness (deev/div). Experiment 2 added accuracy feedback after each trial to remind children of task instructions. Experiment 3 interspersed many "same" trials containing a repeating standard word to assess the role of bottom-up stimulus support on difference detection.

RESULTS

The d' scores were highest for dissimilar words, next highest on different-vowel pairs, and lowest on different-consonant pairs. Performance was better with repeated standard stimuli (Experiment 3) than without (Experiment 1). Benefits for repeated task instructions (Experiment 2) were marginal. Exploratory analyses comparing these results to findings in a word-learning study using the same stimuli suggest an imperfect match to how easily children can learn similar-sounding words.

CONCLUSIONS

Overall, similar-sounding novel words are challenging for children to discriminate perceptually, although discrimination scores exceeded chance for all levels of similarity. Clinically speaking, same/different tests may be less sensitive to sound discrimination than change/no-change tests.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20151848.

Perceptual flexibility in word learning: Preschoolers learn words with speech sound variability

Children's language input is rife with acoustic variability. Much of this variability may facilitate learning by highlighting unvarying, criterial speech attributes. But in many cases, learners experience variation in those criterial attributes themselves, as when hearing speakers with different accents. How flexible are children in the face of this variability? The current study taught 3-5-year-olds new words containing speech-sound variability: a single picture might be labeled both deev and teev. After learning, children's knowledge was tested by presenting two pictures and asking them to point to one. Picture-pointing accuracy and eye movements were tracked. While children pointed less accurately and looked less rapidly to dual-label than single-label words, they robustly exceeded chance. Performance was weaker when children learned two distinct labels, such as vayfe and fosh, for a single object. Findings suggest moderate learning even with speech-sound variability. One implication is that neural representations of speech contain rich gradient information.

Spatial Metaphor Facilitates Word Learning

Why are spatial metaphors, like the use of "high" to describe a musical pitch, so common? This study tested one hundred and fifty-four 3- to 5-year-old English-learning children on their ability to learn a novel adjective in the domain of space or pitch and to extend this adjective to the untrained dimension. Children were more proficient at learning the word when it described a spatial attribute compared to pitch. However, once children learned the word, they extended it to the untrained dimension without feedback. Thus, children leveraged preexisting associations between space and pitch to spontaneously understand new metaphors. These results suggest that spatial metaphors may be common across languages in part because they scaffold children's acquisition of word meanings that are otherwise difficult to learn.