Outcome
Type |
Measure |
Description |
Time frame |
Safety issue |
Primary |
Change from baseline treated sound production accuracy at four months |
Each treated sound will be point-by-point identified as being correct or incorrect in relation to its target phoneme. From these values, generalization data from each child will be examined from both descriptive and quantitative perspectives. Generalization will be descriptively defined using the learning criterion level of 10% or greater accuracy change in treated phonemes (Gierut & Morrisette, 2012a). For each child and each condition, generalization will be examined to see if the 10% criterion is met. Quantitatively, the amount of change from pre- to post-intervention in treated phoneme accuracy will be calculated separately for each child. |
an average of 4 months |
|
Secondary |
Change from baseline Mismatch Negativity (MMN) mean amplitude at four months |
Given that the MMN is typically maximal over fronto-central midline electrode sites (e.g., Fz, FCz, and Cz) (Naatanen, Teder, Alho, & Lavikainen, 1992), these three electrodes will be selected for the mean MMN amplitude analyses. Each maximal peak latency will be first measured in the grand averaged waveforms using the ERPLAB Toolbox (Luck & Lopez-Calderon, 2012) across the 100-400 ms time window. Peak latencies elicited by the treated sound syllable and ba stimuli will be averaged across the three electrodes to determine the center latency of each peak. The center latency will be then used to align a 100 ms window (50 ms on either side) to measure the mean amplitudes for all electrodes and stimulus types. It is likely that the MMN mean amplitude window will be approximately 250-350 ms. |
an average of 4 months |
|
Secondary |
Change from baseline P1/P2 mean amplitude at four months |
As every participant might not demonstrate a clear and measurable MMN peak (Cummings, Madden, & Hefta, 2017), mean amplitude measurements of the auditory P1/P2 ERP peak in the standard and deviant waveforms will also be taken as an additional measure of neural change occurring in conjunction with speech treatment. Three regions of interest (ROI) have been defined and electrodes for each ROI are defined as follows. Left hemisphere ROI channels are F5, FC5, and C5; midline ROI channels are Fz, FCz, and Cz; right hemisphere ROI channels are F6, FC6, and C6. The P1/P2 mean amplitude will be measured across a 100 ms window (100-200 ms post-syllable onset) for both the treated sound syllable and ba for all nine electrodes. The median P1/P2 amplitude for each subject and each ROI for both the pre-treatment and post-treatment assessments will then be calculated. |
an average of 4 months |
|
Secondary |
Event-related spectral perturbation (ERSP) channel analyses |
ERSP channel analyses will be completed to examine theta (3-6 Hz) and alpha (8-13 Hz) band activity changes occurring in conjunction with speech treatment for both the treated sound and ba syllables. Data from all children will be included in the channel analyses. A left hemisphere region of interest (ROI) and a right hemisphere ROI have been identified to include channels associated with right and left IFG. The left ROI includes the following channels: F5, FC5, C5, F3, FC3, C3; the right ROI includes: F6, FC6, C6, F4, FC4, C4. |
an average of 4 months |
|
Secondary |
Change from baseline frequency following responses (FFRs) at four months |
The timing, stability, and magnitude of FFRs elicited by consonants have been linked to children's phonological awareness and literacy skills (White-Schwoch et al., 2015). Thus, FFRs, as well as traditional auditory brainstem response (ABR) peaks, will be measured. For each FFR/ABR peak, grand average latency and amplitude measurements will be completed. |
an average of 4 months |
|
Secondary |
Event-related spectral perturbation (ERSP) independent component (IC) analyses |
ERSP IC analyses will be completed to examine theta (3-6 Hz) and alpha (8-13 Hz) band activity changes occurring in conjunction with speech treatment for both the treated sound and ba syllables. Completing the IC cluster analyses will involve multiple steps. First, the pre- and post-treatment data for the treated sound and ba syllables will be put into separate studies in EEGLAB to examine neural changes occurring in conjunction with speech treatment. EEG component clusters will be identified for each of studies; not every subject is predicted to contribute data to each cluster. To limit the number of analyses, only clusters that have dipoles associated with the right and left inferior frontal gyrus (IFG) will be included. Moreover, the IC cluster analyses will only include data from subjects who have identifiable clusters present in both pre- and post-treatment assessments. |
an average of 4 months |
|
Secondary |
Change from baseline Percent Consonants Correct (PCC) at four months |
All consonants will be point-by-point identified as being correct or incorrect in relation to its target phoneme. From these values, generalization data from each child will be examined from both descriptive and quantitative perspectives. Generalization will be descriptively defined using the learning criterion level of 10% or greater accuracy change in PCC scores (Gierut & Morrisette, 2012a). For each child and each condition, generalization will be examined to see if the 10% criterion is met. Quantitatively, the amount of change from pre- to post-intervention in PCC accuracy will be calculated separately for each child. |
an average of 4 months |
|