Listen up! Developmental differences in the impact of IDS on speech segmentation

Area of Science:

• Developmental Psychology
• Linguistics
• Speech Perception

Background:

• Infants typically segment words from fluent speech by 7.5 months in American English.
• Cross-linguistic studies show difficulties replicating this finding in other languages.
• Input prosody may explain differences in infant word segmentation.

Purpose of the Study:

• Investigate word segmentation in German infants at 7.5 and 9 months.
• Examine the impact of prosodically exaggerated infant-directed speech (IDS) on segmentation.
• Explore cross-linguistic and developmental variations in speech segmentation.

Main Methods:

• German infants (7.5 and 9 months) were tested on word segmentation.
• Speech input was prosodically similar to American English infant-directed speech (IDS).
• Behavioral methods assessed segmentation success.

Main Results:

• Nine-month-old German infants successfully segmented words from exaggerated IDS.
• Seven-and-a-half-month-old German infants did not segment words.
• Exaggerated IDS positively impacted speech segmentation in older infants.

Conclusions:

• Exaggerated infant-directed speech aids infant word segmentation.
• Cross-linguistic differences in segmentation exist beyond input type.
• Developmental changes influence the role of IDS in speech segmentation.