Factors Affecting Nonnative Consonant Cluster Learning

Abstract

Purpose: Nonnative consonant cluster learning has become a useful experimental approach for learning about speech motor learning, and we sought to enhance our understanding of this area and to establish best practices for this type of research.

Method: One hundred twenty individuals completed a nonnative consonant cluster learning task within a speech motor learning paradigm. Following a brief prepractice, participants then practiced the production of eight word-initial nonnative consonant clusters embedded in bisyllabic nonwords (e.g., GD in /gdivu/). The clusters ranged in difficulty according to linguistic typology and sonority sequencing. Acquisition was operationalized as the change across the practice section and learning was assessed with two retention sessions (R1: 30 min after practice; R2: 2 days after practice). We evaluated changes in accuracy as well as in the acoustic details of the cluster production at each time point.

Results: Overall, participants improved in their production of the consonant clusters. Accuracy increased, and duration measures decreased in specific measures associated with cluster production. The change in coordination measured in the acoustics changed both for clusters that were incorrectly produced and for those that were correctly produced, indicating continued motor learning even in accurate tokens.

Conclusions: These results aid our understanding of the complexity of nonnative consonant cluster learning. In particular, both factors related to both phonological and speech motor control properties affect the learning of novel speech sequences.

Supplemental material: https://doi.org/10.23641/asha.21844185.

Figure 1.

Overall accuracy for each consonant cluster class at each time point in the cluster accuracy analysis. Lines indicating baseline performance are provided to help visualize the change. Error bars are standard error. Q1 = first quantile; R1 = short-term retention; R2 = long-term retention.

Figure 2.

Overall burst-to-burst duration in /gd/ and /pt/ clusters at each time point in the analysis. Error bars represent standard error. Q1 = first quantile; R1 = short-term retention; R2 = long-term retention.

Figure 3.

Overall nasal duration in correctly produced voiceless fricative-nasals (fN) cluster at each time point in the analysis. Error bars represent standard error. Q1 = first quantile; R1 = short-term retention; R2 = long-term retention.