Unraveling phonological conspiracies: A case study.

This paper focuses on three seemingly unrelated error patterns in the sound system of a child with a phonological delay, Child 218 (male, age 4 years 6 months) and ascribes those error patterns to a larger conspiracy to eliminate fricatives from the phonetic inventory. Employing Optimality Theory for its advantages in characterizing conspiracies, our analysis offers a unified account of the observed repairs. The contextual restrictions on those repairs are, moreover, attributed to early developmental prominence effects, which are independently manifested in another error pattern involving rhotic consonants. Comparisons are made with a published case study involving a different implementation of the same conspiracy, the intent being to disambiguate the force behind certain error patterns. The clinical implications of the account are also considered.

The coronal fricative problem.

This paper examines a range of predicted versus attested error patterns involving coronal fricatives (e.g. [s, z, θ, ð]) as targets and repairs in the early sound systems of monolingual English-acquiring children. Typological results are reported from a cross-sectional study of 234 children with phonological delays (ages 3 years; 0 months to 7;9). Our analyses revealed different instantiations of a putative developmental conspiracy within and across children. Supplemental longitudinal evidence is also presented that replicates the cross-sectional results, offering further insight into the life-cycle of the conspiracy. Several of the observed typological anomalies are argued to follow from a modified version of Optimality Theory with Candidate Chains (McCarthy, 2007).

On the unity of children's phonological error patterns: distinguishing symptoms from the problem.

This article compares the claims of rule- and constraint-based accounts of three seemingly distinct error patterns, namely, Deaffrication, Consonant Harmony and Assibilation, in the sound system of a child with a phonological delay. It is argued that these error patterns are not separate problems, but rather are symptoms of a larger conspiracy to avoid word-initial coronal stops. The clinical implications of these findings are also considered.

On the interaction of deaffrication and consonant harmony.

Error patterns in children's phonological development are often described as simplifying processes that can interact with one another with different consequences. Some interactions limit the applicability of an error pattern, and others extend it to more words. Theories predict that error patterns interact to their full potential. While specific interactions have been documented for certain pairs of processes, no developmental study has shown that the range of typologically predicted interactions occurs for those processes. To determine whether this anomaly is an accidental gap or a systematic peculiarity of particular error patterns, two commonly occurring processes were considered, namely Deaffrication and Consonant Harmony. Results are reported from a cross-sectional and longitudinal study of twelve children (age 3 ; 0-5 ; 0) with functional phonological delays. Three interaction types were attested to varying degrees. The longitudinal results further instantiated the typology and revealed a characteristic trajectory of change. Implications of these findings are explored.

On the anatomy of a chain shift.

Phonological chain shifts have been the focus of many theoretical, developmental, and clinical concerns. This paper considers an overlooked property of the problem by focusing on the typological properties of the widely attested 's > θ > f' chain shift involving the processes of Labialization and Dentalization in early phonological development. Findings are reported from a cross-sectional study of 234 children (ages 3 years; 0 months-7;9) with functional (nonorganic) phonological delays. The results reveal some unexpected gaps in the predicted interactions of these processes and are brought to bear on the evaluation of recent optimality theoretic proposals for the characterization of phonological interactions. A developmental modification to the theory is proposed that has the desired effect of precluding certain early-stage grammars. The proposal is further evaluated against the facts of another widely cited developmental chain shift known as the 'puzzle > puddle > pickle' problem (Smith 1973).

On the interaction of velar fronting and labial harmony.

This article documents the typological occurrence and interactions of two seemingly independent error patterns, namely Velar Fronting and Labial Harmony, in a cross-sectional investigation of the sound systems of 235 children with phonological delays (ages 3;0 to 7;9). The results revealed that the occurrence of Labial Harmony depends on the occurrence of Velar Fronting, and that, when these processes co-occurred, all three predicted types of interactions were attested. A constrained version of Optimality Theory is put forward that offers a unified explanation for the implicational relationship between these error patterns and their observed interactions. The findings are compared with the results from other studies and are considered for their theoretical and clinical implications.

Comparative Markedness and Induced Opacity.

Results are reported from a descriptive and experimental study that was intended to evaluate comparative markedness (McCarthy 2002, 2003) as an amendment to optimality theory. Two children (aged 4;3 and 4;11) with strikingly similar, delayed phonologies presented with two independent, interacting error patterns of special interest, i.e., Deaffrication ([tɪn] 'chin') and Consonant Harmony ([ɡɔɡ] 'dog') in a feeding interaction ([kik] 'cheek'). Both children were enrolled in a counterbalanced treatment study employing a multiple base-line single-subject experimental design, which was intended to induce a grandfather effect in one case ([dɔɡ] 'dog' and [kik] 'cheek') and a counterfeeding interaction in the other ([ɡɔɡ] 'dog' and [tik] 'cheek'). The results were largely supportive of comparative markedness, although some anomalies were observed. The clinical implications of these results are also explored.

The predictive power of optimality theory for phonological treatment.

The phonology and clinically induced learning patterns of a female child with a phonological delay (age 4;11) were examined from the analytical perspective of Optimality Theory. The analysis revealed that a Consonant Harmony error pattern affected alveolar stops from two different sources-from underlying lexical representations and from representations derived by an interacting error pattern of Deaffrication. The implications of that analysis for the selection of treatment targets were explored in a treatment study. It was found that treatment aimed at the derived source of Consonant Harmony resulted in the suppression of both Consonant Harmony and Deaffrication. The explanation for these results was attributed to a fixed ranking among certain constraints.

Constraint conflict: the source of an unusual error pattern.

Certain phonological error patterns have been judged to be "unusual" or "idiosyncratic", posing a number of theoretical and clinical problems. This paper reconsiders an especially challenging case of an unusual error pattern documented by Leonard and Brown (1984). T (age 3;8) replaced all word-final consonants (except for labial stops) with [s] but more importantly inserted [s] after word-final vowels. Our purpose is to show that optimality theory offers a fresh perspective on this error pattern and its course of development by providing an account of the facts that is entirely consistent with general principles relevant to the description of fully developed languages and acquisition.

Implicationally Related Error Patterns and the Selection of Treatment Targets.

This paper compares some of the different claims that have been made concerning acquisition by traditional rule-based derivational theories and the more recent framework of optimality theory. Case studies of children with phonological delays are examined with special attention given to two seemingly independent error patterns, namely, place harmony and spirantization. Contrary to the expectations of derivational theories, these (and other) error patterns are argued to be implicationally related. Optimality theory is shown to offer a principled explanation for the facts with novel implications for clinical treatment.