INCLUSION CRITERIA:
i. Normal Language Development, Hearing and Cognition
ii. The following screening tests previously published with norms were found to have a good distribution for determining normal functioning in adolescents and adults as all subjects did not hit ceiling and all had scores greater than or equal to the 80th percentile. These tests are being used to ensure that subjects affected with stuttering or FPPD do not have other disorders such as hearing loss, language delay, or mental retardation.
Peabody Picture Vocabulary Test III (PPVT-III)
Expressive Vocabulary Test (EVT)
Oral Speech Mechanism Screening Examination
Revised Token Test; Token test for Children
Test of Non verbal intelligence (TONI-2)
Digit Span subtest of the WICS-R
Audiometric Screening
Goldman Fristoe Test of Articulation
WUG Test of Morphological Encoding
Test of Auditory Comprehension of Language (TACL)
Khan-Lewis Phonological Analysis
INCLUSION CRITERIA FOR IDENTIFYING AND QUANTIFYING STUTTERING:
The Stuttering Severity Index -3 (Riley, 1981) has been found to be accurate for identifying and assessing the severity of stuttering during conversational speech. For the inclusion of a stuttering subject we require:
i. A total overall score of 11 or greater between 3 and 17 years,
ii. A total overall score of 18 or greater from age 18 and above.
INCLUSION CRITERIA FOR IDENTIFYING FPPD:
i. A family history of an autosomal dominant pattern of inheritance of the speech disorder over several generations with persistence into adulthood in some cases,
ii. Speech symptoms during conversational speech include: deletion of final consonants; syllable reduction and syllable deletion; deletion of grammatical markers such as copulas, auxiliaries, prepositions, connectives; poor ability to self-correct; poor awareness of errors; and consonant cluster reduction.
iii. Greater than 9% discourse errors during analysis of a sample of 300 syllables.
iv. A discrepancy of 30 points (1 and 1/2 Standard Deviations) between receptive (the higher score) and expressive percentile score on the PPVT III and Expressive Vocabulary Test.
v. For subjects greater than 7 years of age, a phonological process rating of 3 or more for any phonological process on the Khan-Lewis Phonological Analysis. For subjects less than 7 years of age, a phonological process rating of 3 or more on 2 phonological processes on the Khan-Lewis Phonological Analysis. Finally, any subjects with a non developmental phonological process error will be identified as potentially having FPPD.
EXCLUSION CRITERIA:
i. Anyone with a hearing loss will be excluded from participation during the diagnostic testing.
ii. Children with delayed language, more than 1 year delay from norms on receptive and expression language testing will be excluded.
iii. Language impairment: scores more than 2 standard deviations below the age appropriate score on the standardized language tests listed under the inclusion criteria.
iv. Cognitive impairment: scores more than 2 standard deviations below the age appropriate score on the standardized cognitive tests listed under the inclusion criteria.
v. Bilingual non-native English speakers - Studies have demonstrated that brain organization for speech and language may differ in bilingual persons. It is hypothesized that this may alter speech motor learning and thus kinematic data from non-native English speakers would differ from native English speakers. Therefore, only native-American English speakers, with only one language spoken in the home, will be included.
National Institutes of Health Clinical Center
Bethesda, Maryland 20892. Last update: 09/16/2008