Simplification of /s/ + Stop Consonant Clusters

Abstract

This longitudinal study examined individual patterns and changes in /s/ + stop cluster simplifications of six normally developing children. Subjects produced selected words containing initial voiced and voiceless stops and /s/+ stop clusters at monthly intervals. Speech samples were transcribed phonetically, and voice onset times (VOT) of the stop consonants were measured. The results revealed that subjects reduced clusters most frequently to stop consonants with short-lag VOTs. However, two children also occasionally employed prevoicing, and one subject used long-lag VOTs in cluster-reduced stops. Because cluster-reduced stops and voiced singleton stops were generally produced with similar VOTs, it was concluded that subjects represented clustered stops most frequently as phonemically voiced.

Diversity not quantity in caregiver speech: Using computational modeling to isolate the effects of the quantity and the diversity of the input on vocabulary growth

“…CLASSIC's learning is based on two assumptions: (a) that regularly occurring sequences (be they sequences of phonemes or words) will eventually be learned as chunks; and (b) that the processing of a sequence is facilitated when the sequence can be coded using few, rather than many, chunks (see Table 1). Sublexically, these assumptions are based on robust evidence that children and adults find it easier to process and produce a phoneme sequence if they have previously been exposed to it as a sequence, than if they have simply been exposed to its component phonemes in separate phonological contexts (e.g., Catts & Kamhi, 1984;Demuth, Culbertson, & Alter, 2006;Jakobson, 1941Jakobson, /1968). For example, even when children are able to produce all constituent sounds in a phoneme sequence, they are more accurate at producing those sequences that exist in the native language over those that do not (Beckman & Edwards, 1999).…”

The sbelling of sdops: Preliterate children’s spelling of stops after /s/

“…Experiment 2 aimed to rule out the possibility that the difference between adult and child perception of these sequences stems from differences in production. Though children aged 2 and 3 often have trouble pronouncing s-stop clusters, normal children can do this before entering preschool (Catts & Kamhi, 1984). But do they do so in a way similar to adults?…”

Electropalatographic (EPG) evidence of covert contrasts in disordered speech

“…Both temporal and spectral measures derived from acoustic recordings have revealed the presence of different types of covert contrasts. Voice onset time (VOT) has probably been the temporal cue most frequently measured and has been used to investigate the voicing distinction in a variety of contexts such as: word-initial and word-final stops, cluster reduction (Catts & Kamhi, 1984;Gierut & Dinnsen, 1986;Macken & Barton, 1980;Maxwell & Weismer, 1982;Tyler, Edwards, & Saxman, 1990), fricative stopping (Tyler, 1995) and velar fronting (Young & Gilbert, 1988;Tyler et al, 1990). Other duration measurements that have been used to uncover instances of covert contrast include vowel durations preceding deletion of final stops and clusters (Camarata & Gandour, 1985;Catts & Jensen, 1983;Riley, Hoffman, & Damico, 1986;Smit & Bernthal, 1983;Weismer, Dinnsen, & Elbert, 1981), duration of laterals (McLeod & Isaac, 1995) and stop duration following deleted fricatives in /s/ plus stop clusters (Weismer, 1984).…”