Vowel systems of normally developing and phonologically disordered children

Area of Science:

• Speech-Language Pathology
• Developmental Linguistics
• Childhood Communication Disorders

Background:

• Vowel acquisition is a critical aspect of speech development.
• Understanding typical and disordered phonological development aids intervention.
• Existing literature highlights patterns in normal and disordered vowel learning.

Purpose of the Study:

• To review literature on vowel acquisition in typical and phonologically disordered children.
• To present case studies of vowel production in two phonologically disordered children.
• To compare disordered and typical vowel acquisition patterns.

Main Methods:

• Literature review of vowel acquisition studies.
• Detailed case study analysis of two children with phonological disorders.
• Analysis of vowel production accuracy and order.

Main Results:

• Disordered and typical vowel acquisition show similar patterns.
• Corner vowels (e.g., /i/, /u/, /a/) are acquired before non-corner vowels.
• Unstressed vowels present significant difficulties for children with phonological disorders.

Conclusions:

• Phonologically disordered children's vowel development parallels typical acquisition timelines.
• Targeting corner vowels early may be beneficial for intervention.
• Specific attention to unstressed vowel production is needed for these children.