Faculty Collaboration Database

Developmental trajectories of forward and backward digit spans in deaf children with cochlear implants. Cochlear Implants Int 2011 May;12 Suppl 1(Suppl 1):S84-8

Date

08/04/2011

Pubmed ID

21756483

Pubmed Central ID

PMC3304450

DOI

10.1179/146701011X13001035752534

Scopus ID

2-s2.0-84855171139 (requires institutional sign-in at Scopus site)   17 Citations

Abstract

BACKGROUND: Accounting for outcome variability among pediatric cochlear implant (CI) recipients is an enduring clinical challenge. Short-term memory and working memory (STM/WM), as indexed by digit span forward (DSF) and digit span backward (DSB), have been shown to be strongly correlated with speech and language (S/L) outcomes. The enormous variability observed in conventional outcome measures of S/L may reflect individual differences in STM/WM.

METHODS: Repeated measure auditory digit spans were obtained from 110 children (age 3-15 years; mean 7.2 years) with at least 2 years of CI use. Growth curves were computed for each child, and linear functions were fit to both DSF and DSB. Slopes and intercepts were used as parameters in mixed-models to assess relations between STM/WM capacity change over time and S/L outcome measures including vocabulary (PPVT), open-set set spoken word recognition (PBK), and sentence perception (HINT-C).

RESULTS: For DSF, the percent of the sample more than 1 SD below the norm at each age ranged from 54 to 90% (mean = 66.5%). For DSB, the percent of the sample more than 1 SD below the norm at each age ranged from 23 to 42% (mean = 34.5%) at ages where there were at least five children. Four subgroups within our CI sample emerged: (Subgroup 1) children demonstrating age-appropriate growth in both DSF and DSB scores over time (49/110, 44.55%); (Subgroup 2) children demonstrating age appropriate growth in DSF over time but below average growth in DSB over time (23/110, 20.91%); (Subgroup 3) children demonstrating below average growth in DSF over time but age-appropriate growth in DSB over time (19/110, 17.27%); and (Subgroup 4) children demonstrating below average growth in both DSF and DSB over time (19/110, 17.27%). For all tests except CELF-3, Subgroup 4 demonstrated the poorest performance among the four DS slope subgroups. Significant differences were observed between Subgroup 1 and Subgroup 4 on last visit PBK-Word (P = 0.029), PPVT (P = 0.018), and HINT-C in Quiet (P = 0.001), but not CELF-3 (P = 0.433).

CONCLUSION: The findings from this longitudinal study suggest that differences in the rate of development of STM/WM may influence S/L outcomes in children with CIs. The clinical implications of these findings are significant because they indicate that the rate of development of STM/WM, and not just the actual level of STM/WM at a single time point, predicts later S/L development in this clinical population. Targeted interventions to improve developmental rate of verbal STM/WM may hold promise for enhancing S/L skills in children with CIs.

Author List

Harris MS, Pisoni DB, Kronenberger WG, Gao S, Caffrey HM, Miyamoto RT

Author

Michael S. Harris MD Associate Professor in the Otolaryngology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adolescent
Age Factors
Child
Child, Preschool
Cochlear Implantation
Cochlear Implants
Cohort Studies
Deafness
Female
Humans
Language Development
Male
Memory, Short-Term
Speech Perception
Treatment Outcome