Infant-Directed Speech in the UK and US
The study in a sentence
Before babies can learn words, they have to be able to recognise where words begin and end in the speech that they hear around them. This study raises the possibility that known differences between the typical properties of Infant Directed Speech in American English versus British English may explain the fact that UK babies typically display ability to recognize words in running speech later than US babies. We also suggest other ways to interpret the findings of this study.
Researchers on child language development use the term infant to describe a child who is not yet speaking or producing any language, i.e. babies under the age of 18-24 months.
Infant Directed Speech (IDS) is known to have a specific set of properties, such as more varied and expanded use of pitch. Previous research has shown that there are differences between the IDS produce by caregivers who are speakers of American versus British English. This study explores whether these differences in the properties of IDS have an impact on babies' language development.
Word segmentation is the task of identifying where words begin and end in the continuous stream of sound that we hear when we listen to speech. If you listen to speech in a language which you don't know, it can be difficult, if not impossible, to say where one word ends and another word begins. Successful word segmentation is a necessary step on the way to learning new words; to learn words, and to recognise the words we have learned in others' speech, we need to know which sequences of sounds are possible words.
Do differences in the properties of US and UK Infant-Directed Speech matter?
How can we work out which words babies do or don't recognise?
The Head-Turn Preference procedure is a well-established method of measuring what babies and infants pay attention to. The video explains how the procedure works.
The authors of this study between them carried out fourteen (14!) different studies with babies in the UK and the USA, but babies displayed ability to segment words in running speech in only one study. This contrasts with findings of earlier studies in which babies of the same age or younger learning American English and several other languages did display ability to segment words
The one study which showed a positive result for British babies used recordings of IDS which had much more exaggerated features than is typical for IDS produced by British English speakers.
In more detail
A longer explanation of the research study
Talk 1 (6 mins)
Talk 2 (12 mins)
Talk 3 (12 mins)