Speech sample effects on pressure and flow measures in children with normal or abnormal velopharyngeal function.

Area of Science:

• Speech-language pathology
• Pediatric audiology
• Physiological acoustics

Background:

• Velopharyngeal (VP) function is crucial for distinguishing oral and nasal speech sounds.
• Understanding VP function in children informs diagnosis and treatment of speech disorders.
• Previous research has not fully elucidated the impact of phoneme context on oral pressure and nasal flow in children with varying VP function.

Purpose of the Study:

• To investigate how different speech sound contexts affect oral pressure and nasal flow in children with normal velopharyngeal function.
• To compare these effects with those observed in children exhibiting velopharyngeal incompetence.
• To identify specific phoneme contexts that may be more revealing for assessing velopharyngeal function.

Main Methods:

• Simultaneous oral pressure and nasal flow measurements were recorded in two groups of children: 10 with normal VP function and 5 with VP incompetence.
• Speech stimuli included /p/ sounds in varied syllable positions, adjacent vowel heights, and consonant characteristics.
• Analysis focused on within-subject differences in pressure and flow across different stimulus conditions.

Main Results:

• Children with normal velopharyngeal function showed minimal effects of speech sample context on oral pressure.
• Nasal flow was infrequent in the normal VP function group but present in 80% of subjects.
• Children with VP incompetence exhibited predictable context effects, including higher nasal flow and lower oral pressure in nasal contexts, and higher nasal flow with high vowels.

Conclusions:

• Stimulus selection for normative oral pressure studies in children with normal VP function requires minimal consideration of phoneme context.
• Specific phoneme contexts are critical for accurate assessment when evaluating children with abnormal velopharyngeal function.
• These findings aid in refining diagnostic protocols for velopharyngeal disorders in pediatric populations.