Poster #157 - Fine Motor Skill Predicts Growth in Expressive Vocabulary from 12 to 24 Months

• In Event: 3-159 - Poster Session 12
  In Poster Session: PS 12 Section - Perceptual, Sensory, Motor

Integrative Statement

Changes in motor ability can alter the opportunities for learning an infant may experience (Campos et al., 2000; Gibson, 1988). In particular, learning a new motor skill can increase production of other behaviors, setting off a cascade of changes in other cognitive systems (Campos et al., 2000). In particular, individual differences in motor skills in infancy have been linked to language outcomes. Previous research demonstrates that walking onset is predictive of immediate increases in receptive and productive language, with walkers also demonstrating larger receptive and productive vocabularies compared to same aged crawlers (He, Walle, & Campos, 2015; Walle & Campos, 2014). Research focusing on fine motor skills has found that infant siblings of children with Autism Spectrum Disorder (ASD) demonstrate delays in fine motor skills compared to infants at low risk for ASD. Moreover, the severity of the fine motor delay is related to later ASD diagnosis (Lebarton & Iverson, 2013). To date, research on motor-language cascades has largely focused on motor skill level in relation to language outcome at individual time points. Knowledge regarding the role of motor development on language growth over time is limited. Moreover, research on motor-language cascades has not capitalized on time points spanning the second year of life, when language development is rapidly transforming.
The current study aimed to investigate the role of motor development as a predictor of language growth during the second year of life. Infants (N = 98; 46 female) participated in a longitudinal study measuring motor development at 12 months and productive vocabulary at 12, 18 and 24 months. Motor skills were assessed using the Mullen Scales of Early Learning (MSEL), which includes fine motor (FM) and gross motor (GM) subscales. Data regarding productive vocabulary size was collected using the MacArthur Bates Communicative Development Inventories (MCDI). Rate of productive language growth was determined by calculating the linear slopes across 12, 18, and 24 month language time points per participant. A multiple regression analysis was conducted with 12 month GM and FM standard scores predicting MCDI expressive vocabulary growth from 12 to 24 months, with maternal education included as a covariate. Multiple imputation was applied to address missing data across time points. FM score at 12 months was a significant predictor of MCDI expressive vocabulary growth from 12 to 24 months, above and beyond GM scores and maternal education level, t(96) = 2.372, R2= .106, β = .316, p = .018 [95% CI = (.263, 2.794)]. Neither GM scores nor maternal education were significant predictors of MCDI expressive vocabulary growth in the present sample (ps > .05, see Table 1). Thus, greater fine motor skills at 12 months predicted faster language growth over 12 to 24 months. It is possible that infants with better fine motor skills at 12 months are more likely to experience novel interactions with objects in their environments and with caregivers, allowing for more language learning opportunities. These data are the first to address growth in language during the “word spurt” from a motor-language cascade perspective.

Authors

• Sandy Gonzalez, Florida International University
  Presenting Author

• Bethany Reeb-Sutherland, Florida International University
  Non-Presenting Author

• Eliza L Nelson, Florida International University
  Non-Presenting Author