Topic choice, topic synchrony, and utterance function during mother-child p
lay sessions at age 3 were examined in 32 late talkers (identified at 24 to
31 months) and 21 comparison children, matched at intake on age, SES, and
nonverbal ability. At age 3, late talkers bad significantly lower MLUs and
IPSyn scores than comparison children. Late talkers and comparison children
did not differ in number of utterances, topic initiation, topic synchrony,
use of commands, reactions to commands, or conversational fillers. However
, late talkers asked significantly fewer questions, provided fewer answers
to maternal questions, made fewer declarative statements, and were less lik
ely to elaborate on their own topic than comparison children. Mothers of la
te talkers produced significantly more utterances and asked many more quest
ions, but otherwise they did not differ from mothers of comparison children
. In both groups, children and mothers were highly synchronous. When late t
alkers were divided into two groups (children with continuing delay vs. "la
te bloomers" who were within the normal range in MLU), the subgroups did no
t differ significantly from each other on any conversational measure.