This article presents a test of the proposal that a subgroup of children with GRAMMATICAL-SPECIFIC LANGUAGE IMPAIRMENT (G-SLI) have optional movement (the REPRESENTATIONAL DEFICIT FOR DEPENDENT RELATIONS (RDDR) account, van der Lely 1998) by investigating WH-movement in fifteen G-SLI subjects and twenty-four younger children matched on language abilities (LA controls). The RDDR/optional movement account predicts that G-SLI subjects would have deficits with both WH-operator and Q-feature movement and therefore would have particular problems producing object questions. We elicited 36 questions balanced for subject and object questions and WH-words (who, which, what). The G-SLI subjects were significantly impaired in producing WH-questions, showing particular difficulties with object questions in relation to the control children. The majority of G-SLI subjects (80%) evinced both WH-operator and T/Q-feature movement errors whereas only one control child (4%) did so, yet on occasion all the G-SLI subjects used appropriate movement operations to satisfy the WH-criterion. We conclude that the RDDR account whereby movement is optional is consistent with the findings of correct and incorrect WH-question formation. Thus, this first test of the RDDR account of G-SLI is supported by the findings. We discuss the possible underlying nature of a grammar that could cause such optionality, the implications for normal and impaired language acquisition, and the generalizability of the findings to other groups of children with SLI. We propose that in the face of no movement, the WH-word and, on occasion, do are merged in situ in the CP, and function as an interrogative adjunct.

There is a long-standing debate about the principles constraining the combinatorial properties of suffixes. Hay 2002 and Hay & Plag 2004 proposed a model in which suffixes can be ordered along a hierarchy of processing complexity. We show that this model generalizes to a larger set of suffixes, and we provide independent evidence supporting the claim that a higher rank in the ordering correlates with increased productivity. Behavioral data from lexical decision and word naming show, however, that this model has been one-sided in its exclusive focus on the importance of constituent-driven processing, and that it requires supplementation by a second and equally important focus on the role of memory. Finally, using concepts from graph theory, we show that the space of existing suffix combinations can be conceptualized as a directed graph, which, with surprisingly few exceptions, is acyclic. This acyclicity is hypothesized to be functional for lexical processing.

Among the common strategies for eliminating vocalic hiatus is vowel elision. In some cases, it is the first vowel (V1) that elides, while in others it is the second (V2). Analyses of elision have, virtually without exception, simply stipulated which vowel is elided, for example, by encoding this information directly in a language-specific rule. This implies that the targeted position is not predictable, but simply a matter of which of two equally available options is selected by the language. A cross-linguistic study suggests, however, that this is not strictly the case, but that in some environments the choice of target is universally determined. This article accounts for the observed restrictions on elision target within a constraint-based theory which claims that languages preferentially preserve phonological elements in certain prominent positions.