Related Experiment Video
Updated: Aug 13, 2026
Behavioral Assessment of Hearing in 2 to 4 Year-old Children: A Two-interval, Observer-based Procedure Using Conditioned Play-based Responses
Published on: January 23, 2017
Differences in Toddlers' inhibitory control performance across phases with and without sound-absorbing materials in a
Yohko Shimada1, Yuki Ito2, Shoji Itakura3
1Organization for Research Innovation, Doshisha University, Tatara-miyakodani, Kyotanabe, Kyoto 610-0394, Japan; Laboratory of Developmental Neurobiology, Graduate School of Brain Science, Doshisha University, Tatara-miyakodani, Kyotanabe, Kyoto 610-0394, Japan; Centre for Baby Science, Doshisha University, Tatara-miyakodani, Kyotanabe, Kyoto 610-0394, Japan.
Objective:
To examine whether toddlers' IC-related performance differed across classroom periods with and without sound-absorbing materials.
Methods:
A field-based alternating intervention was conducted in a Japanese nursery classroom (N = 30; age = 24.3-39.3 months). Sound-absorbing materials were installed during two phases and removed during an intervening phase. Existing classroom recordings from four days in each phase were analyzed to characterize sound levels and reverberation times were measured across two phases. IC was assessed using a delay-of-gratification task and analyzed using logistic mixed-effects models. Teachers also completed the Self-Regulation Assessment Scale for Early Childhood for a subset of children.
Results:
Modest reductions in reverberation time and sound levels were observed during the phases with the sound-absorbing materials installed. Children showed significantly higher odds of task success during both With-installation phases than during the Without-installation phase, although individual response patterns were heterogeneous. The proportion of children waiting successfully for 300 s was lowest during the Without-installation phase, but substantial individual variability was observed. Teacher ratings collected for a limited subset of children showed a broadly similar pattern.
Conclusions:
Toddlers' IC-related performance differed across classroom periods with and without sound-absorbing materials. These findings provide preliminary field-based evidence that the classroom intervention may have modified multiple aspects of the classroom environment, including teachers' behaviors and teacher-child interactional processes, thereby contributing to variation in toddlers' IC-related performance. Future studies should determine the relative contributions of acoustic and non-acoustic pathways underlying these intervention-related changes.
