English-hearing toddlers learn words from consistent and variable labels.

Area of Science:

• Developmental Psychology
• Linguistics
• Cognitive Science

Background:

• Early word learning traditionally assumes a single label per referent.
• Child-directed speech (CDS) often uses multiple labels, including diminutives and reduplications, for the same object.
• Understanding how label variation affects word acquisition is crucial for developmental research.

Purpose of the Study:

• To investigate the impact of consistent versus variable labels on children's novel word learning.
• To determine if typical child-directed speech (CDS) variants aid or hinder word acquisition compared to consistent labels.
• To explore the role of attentional engagement in word learning under different labeling conditions.

Main Methods:

• An eye-tracking experiment with 18- to 36-month-old children learning novel object names.
• Exposure to objects named with consistent labels, typical CDS variants (e.g., 'doggy'), or atypical CDS variants.
• Measurement of word-recognition accuracy via looking time and moment-by-moment attention using pupil size synchrony.

Main Results:

• Children demonstrated reliable word learning with consistent labels and typical CDS variants.
• Word learning was less successful with atypical CDS variants.
• Attentional engagement was higher in both typical and atypical variation conditions compared to the consistent condition, peaking with typical variations.

Conclusions:

• Children can successfully learn new words despite encountering multiple label variations.
• Increased attentional engagement, particularly with typical CDS variants, may facilitate early word learning.
• Label variation in child-directed speech can support, rather than impede, the word learning process.