Temperament and Vocalization Associations in Typically Developing Infants

• In Event: Poster Session 12
  In Poster Session: PS 12 Topic - Language, Communication

Abstract

Introduction: Limited research has investigated the relationship between temperament and vocalization patterns in infancy. Previous studies have found that attentional control and self-regulation are predictors of enhanced verbal language skills in infants (Dixon & Shore, 1997; Gartstein, Crawford, & Robertson, 2008). Duration of orienting is a temperament category that incorporates the use of attentional control. Smiling and laughter and soothability are categories that use self-regulation. These skills support early language acquisition in infants by allowing the infant to be more aware of their surroundings and to focus their attention on learning object labels provided by caregivers (Dixon & Smith, 2000; Morales et al., 2000).
Objective: This study sought to expand upon previous research by investigating the association between infant temperament and infant vocalization counts. The objective was to evaluate the association between three temperamental subscales (duration of orienting, smiling and laughter, and soothability) and infant vocalization count. Additional exploratory analyses were performed to look at the association between negative affective temperament and infant vocalization count.
Methods: Participants (n=35) were part of a longitudinal, prospective study. Seventy-seven percent of infants were reported to be white (n=27), 6% African American (n=2), and 17% reported two or more races (n=6). Infants were included in the study if they had home language recording and temperament data. Infant vocalization count was derived from LENA language recorders at 9 and/or 15 months of age. Child vocalization count (CVC) was a measure of the number of speech-like vocalizations produced by the infant (crying and vegetative sounds are excluded). Temperament was measured using the parent-report Infant Behavior Questionnaire-Revised (IBQ-R; Garstein & Rothbart, 2002). The IBQ-R was completed between 6-14 months of age with the earliest recorded IBQ-R scores for each infant analyzed in this study. The current study focused on the following three IBQ-R subscales: duration of orienting, smiling and laughter, and soothability. Additional exploratory analyses looked at the negative affectivity IBQ-R scale which consists of the subscales distress to limitations, falling reactivity/rate of recovery, fear, and sadness. Analyses using partial correlations were performed controlling for chronological age at IBQ-R.
Results: Results indicated a significant negative correlation between falling reactivity and CVC at 9 months (p = .048), and a significant positive correlation between distress to limitations and CVC at 15 months (p = .011) (Table 1). These results indicate that infants who cry and fuss more and have a longer rate of recovery after distress also had higher speech-like vocalizations counts. The remaining IBQ-R subscales were not significantly associated with CVC.
Discussion: Contrary to previous literature, analyses showed that duration of orienting, smiling and laughter, and soothability were not significantly associated with infant speech-like vocalizations. However, falling reactivity had a significant negative correlation to CVC at 9 months and distress to limitations had a significant positive correlation to CVC at 15 months of age. Due to the differences between this study and other previous findings, future investigations should seek to look at the mechanisms of temperament that play a role in promoting improved infant vocalization skills.

Group Authors

The IBIS Network

Authors

• Shalomi Shelton, University of Texas at Dallas
  Presenting Author

• Allison Bradshaw, University of Texas at Dallas
  Non-Presenting Author

• Shruthi Ravi, University of Texas at Dallas
  Non-Presenting Author

• Sarah Paterson, James S McDonnell Foundation
  Non-Presenting Author

• Stephen Dager, University Of Washington
  Non-Presenting Author

• Annette Mercer Estes, Uniiversity of Washington
  Non-Presenting Author

• Heather Cody Hazlett, University of North Carolina at Chapel Hill
  Non-Presenting Author

• Robert Schultz, Children's Hospital of Philadelphia
  Non-Presenting Author

• Lonnie Zwaigenbaum, University of Alberta
  Non-Presenting Author

• Joseph Piven, University of North Carolina at Chapel Hill
  Non-Presenting Author

• Meghan Swanson, University of Texas at Dallas
  Non-Presenting Author