Natural domains of cyclicity in phonological acquisition

This study expands and further validates cyclicity in the course of phonological development by exploring a potential relationship between the acquisition of singletons and clusters. The hypothesis is that children will acquire singletons followed by clusters in an alternating and recursive pattern, in complement to observed subsegmental cyclicity involving larnygeal and supralaryngeal distinctions. Six children with functional phonological disorders participated in one of three experimental conditions administered as a staggered multiple-baseline, multiple-probe design: treatment of singletons only, clusters only, or the singleton-cluster cycle. Results indicated that a singleton-cluster cycle could be induced experimentally, but it was not generally sustained by a child in expansion of the phonological repertoire. In comparison, laryngeal-supralaryngeal cyclicity was consistently maintained by all children, independent of experimental condition. A theoretical implication of these findings is that cyclicity functions as a governing principle of phonological development, but only if it is inherent to the natural domain of language. The clinical application of cyclicity in structuring treatment is considered.