Date of Award


Publication Type

Doctoral Thesis

Degree Name




First Advisor

McCabe, Ann,


Psychology, Developmental.




The present study examined the early vocabularies and conversational turn taking behaviours of laterborn and firstborn children. Subjects consisted of five laterborn males, six laterborn females, five firstborn males, five firstborn females and their families. Participants were videotaped in their homes during a family meal with both parents present. An initial taping occurred when the target children were at the early stages of multiword speech (mean MLU 1.94) and a follow-up taping occurred six months later (mean MLU 2.71). Data on twenty children and their families were available at the initial taping, while data on fourteen subjects were available at the follow-up taping. Of primary interest was the frequency with which children "intruded" into the conversations of others. While laterborn children were found to intrude into ongoing conversations significantly more often than their firstborn counterparts at both tapings, they did not use proportionally more semantically relevant intrusions than did firstborns at either taping. Neither laterborns nor firstborns demonstrated any significant increase in their ability to intrude with comments that contained new information and were pertinent to the ongoing conversations. It was argued that the environments of laterborns provided them with more models of intrusive behaviour and a greater need to use intrusions as a means of joining conversations or having their needs met. It was also suggested that the two groups may have formulated different perceptions or "rules" for engaging in multiparticipant discourse. Children's language was also examined with respect to MLU, expressive vocabulary size, noun and pronoun usage, and receptive vocabulary size (initial taping only). No statistically significant differences emerged, with the exception that firstborn early expressive vocabularies tended to include more nouns. The results indicated that with respect to these aspects of syntactic and semantic development, laterborn and firstborn children appeared to be acquiring language in a similar manner.Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1996 .R62. Source: Dissertation Abstracts International, Volume: 57-07, Section: B, page: 4751. Adviser: Ann McCabe. Thesis (Ph.D.)--University of Windsor (Canada), 1996.