Why volubility can predict the success of cochlear implantation

Abstract

Background We sought to identify potential communication markers predicting the success of cochlear implantation, that might be observed within the first year of life. According the last ten years literature review volubility can be considered as a potentially important vocal measure predicting later language development. Aims The present review aims to review existing evidence related with: (i) why volubility posits a plausible marker of cochlear implantation success in infancy, and (ii) presents the clinical usefulness of volubility data in predicting later language trajectory. Methods Rate of vocalization or volubility measured in terms of frequency of syllable production and it is clearly affected by parental interactivity. A low percentage of volubility can be predictive of significant communication impairment. Vocalization growth during the first year of life, as demonstrated in publications examining sound production characteristics of normally hearing (NH) and hearing impaired (HI) infants fitted with CI, were reviewed. Results Literature results revealed differences in linguistic performance among NH and CI infants which are typically attributed to auditory deprivation. Infants received late CI, produce fewer syllables (low volubility) and exhibit lateonset babbling, especially those who underwent the procedure as late as the age of 12 months or thereafter. Early recipients (implanted before the age of 12-months) related with more vocalizations, which is thought to stem from CI-initiated auditory feedback. In sum, total syllables produced (volubility) demonstrate the developmental trajectory of language acquisition which in turn is a crucial factor related with the success of cochlear implantation. Conclusion Contemporary findings collectively endorse volubility as a plausible criterion of differentiation between successful and non-successful early CI. It is argued that volubility measures predict language development and, in doing so, carry vast implications on designing efficient clinical assessment and intervention practices.