Effects of integral stimulation therapy on speech - Portland State ...

Data Results for Interdental Fricatives: /θ / and /ð /
Figure 4 illustrates CP’s performance during speech probes as the percent <strong>of</strong>
interdental fricatives /θ/ and /ð/ correctly produced. Data were charted over time during
baseline, treatment, and post treatment phases. Pre treatment data probes indicated that
CP made a variety <strong>of</strong> substitution errors and omissions when attempting interdental
fricative sounds. Most notable was his tendency to substitute bilabial fricatives /Ȉ/ and
/β/ in place <strong>of</strong> /θ/ and /ð/ phonemes in the majority <strong>of</strong> substitution errors. This pattern
was also observed in his attempts to approximate interdental sounds /f/ and /v/. CP
substituted /v/, /d/, /z/, and /f/ sounds in initial word positions and /f/ in final positions.
CP demonstrated consistent levels <strong>of</strong> performance (0% correct) on speech probes during
baseline sessions (22 through 26). Sessions 27 through 37 include data probes gathered
after treatment had begun and before the post treatment period. Data gathered over 12
treatment sessions show CP responding to treatment with variable results. Accuracy <strong>of</strong> /θ/
and /ð/ phonemes ranged from 0 to 60% correct. Despite a short treatment period and
fluctuating performance, CP’s accuracy showed a pattern <strong>of</strong> increased improvement over
the course <strong>of</strong> the treatment. His baseline accuracy for interdental fricatives was
consistently at 0%. After 4 treatment sessions, his performance increased, but then
decreased following 3 cancelled sessions due to illness. CP continued to show symptoms
<strong>of</strong> congestion even after he returned to speech <strong>therapy</strong>.
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