Effect of Music Intervention on Infants' Brainstem Encoding of Speech
Phase: NA
Conditions: Infant Development
Sponsor: University of Washington

Title: Effect of music intervention on infants' brainstem encoding of speech 
NCT number: 04509739 
Date: 09/03/2020 
 
 

Study Protocol 
The objective of the proposed music intervention is to standardize the procedures in 
which the intervention is carried out such that 1) it matches the music intervention in our 
previous study and that 2) it can be replicated in the future to include new outcome measures.  
The data from this intervention will be compared to a control group and we hypothesize that 
the intervention group will exhibit enhanced post-intervention measurement at 11 months of age 
in comparison to the control group. 
Families with healthy infants with no family history of hearing, speech and communication 
disorders will be recruited at 7 months of age to participate in the longitudinal music intervention 
study (Aim 2) that will last for about 4 months. At recruitment, infants with 3 or more ear 
infections and infants who have already been/ have had participated in infant music classes will 
be excluded.  
Infants will complete a pre-intervention brainstem measures at 7 months of age upon 
enrolling in the study: the frequency-following response measure (FFR). Participants will have to 
complete the measurement to proceed to the intervention phase.  
The music intervention starts at 9 months of age if the participants completed the pre-
intervention measurement at 7 months of age. The 12-session intervention (15 minutes per 
session) is intended to last for a 4-week period with 3 sessions/week. It can last for as long as 5 
weeks if some sessions are missed. Participants have to complete all sessions to be eligible for 
post-intervention measurements. During each session, a facilitator will guide the caregivers to 
interact with infants by synchronizing infants’ movement to musical beats. At 9 months of age, 
families will start the 12-session intervention in a controlled laboratory space. In the initial 
session, caregivers will be given a brief orientation to intervention, including introducing them to 
the musical toys they will be using during the sessions with their infants and the lab 
environment. They will also be trained technics through which they can synchronize the infant’s 
movements to the experimenter’s movements, such as clapping hand, tapping feet. The 
remaining sessions will be scheduled in groups of 2-3 infant/parent dyads. In each session, a 
music CD with 15 minutes of selected children’s music will be played and a musically trained 
experimenter will facilitate the sessions to engage the infants and parents to move to musical 
beats, using different musical toys, such as infant drums and maracas. Parents will be 
instructed to not to repeat any of these activities outside of the lab setting for the period of the 
study. Upon finishing the intervention, infants will repeat the FFR measurement at 11 months of 
age.  
 
 

Statistical Design and Powers 
Our a priori power analysis is based on two previous studies in our lab that delivered 
similar foreign language or music intervention during the same period in development with 
behavioral/electrophysiological outcome measures post intervention [7,24]. In both studies, the 
comparisons were only at post-intervention between the intervention group and the control 
group. In the language intervention study, the intervention group exhibited higher consonant 
discrimination (M=65.7, SE=2.4) then control (M=56.7, SE=2.3) and in the music intervention, 
the main effect of intervention in the ANOVA model had an effect size η2 of 0.12. Using the 
G*Power software, it shows that to detect a similar between group effect, a total of 40 subjects 
at a level significance level of 0.05 will yield power above 0.90.