Regular and irregular inflectional morphology in German Williams syndrome

Inflection in Williams Syndrome

“…These results are similar to those of Clahsen & Almazan (1998) and Clahsen, Ring et al (2004) for the English past-tense in WS. Penke & Krause (2004) argued that these results support the view that irregular inflection is selectively impaired in WS. Lukács, Pleh, and Racsmany (2004) tested regular and irregular forms of nouns in Hungarian in 14 adolescents with WS (mean age: 13;2 years) and two control groups of 15 participants each, one matched for chronological age and one matched for verbal mental age (based on a vocabulary test).…”

“…Several previous studies found that people with WS achieved high accuracy levels on regular inflection, whereas on irregular inflection they performed much worse than controls and more often produced overregularizations (see e.g., Clahsen et al, 2004a;Penke & Krause, 2004;Varlokosta et al, 2008). Together with other findings, this contrast between regular and irregular inflection has been argued to reflect a selective impairment of lexically-based (irregular) inflection, with rule-based (regular) inflection being unimpaired (Clahsen & Almazan, 1998).…”

“…Note, however, that this does not explain why in the judgment task, the WS group achieved the same high accuracy scores for existing nonsigmatic verbs as for sigmatic ones. Moreover, Penke and Krause's (2004) study of participle and noun plural inflection in German-speaking individuals with WS revealed better performance on regulars than on irregulars despite the fact that in German the regular forms are not more frequent than the corresponding irregular ones. Taken together these findings indicate that people with WS do not simply favor high-frequency patterns, but that across different languages, they are impaired in retrieving irregular forms from the lexicon (even if they are highly frequent in the language) and that they overrely on regular inflection, as revealed, for example, by higher overregularization rates than those seen in unimpaired children.…”

“…For WS, such studies are extremely scarce; we are aware of just three studies. Penke & Krause (2004), investigating past participle formation in five German-speaking individuals with WS (verbal mental age: 6;5-9;7) and 21 individually matched controls, found that whilst regular -t suffixation was unimpaired, with a mean accuracy score of 98%, the score for irregular participle formation with -n was much lower (73%). Moreover, the participants with WS had high -t overregularization rates, even for high-frequency irregulars (unlike the controls), and did not produce any overapplications of irregular inflection.…”

Genes, language, and the nature of scientific explanations: The case of Williams syndrome

“…In other words, the results support the conclusion that (a) is true. More generally, there is evidence that the same conclusion holds for knowledge of a number of other core grammatical principles that have been investigated in people with WS, including knowledge of the principles underlying the production and comprehension of relative clauses (Zukowski, 2004 Zukowski, 2008), binding and passives (Bellugi et al, 1990; Clahsen & Almazan, 1998; Ring & Clahsen, 2005; Perovic and Wexler, 2007), regular morphology (Bromberg, Ullman, Marcus, Kelly, & Levine, 1995; Clahsen et al, 2004; Pléh, Lukács, & Racsmány, 2003; Clahsen & Almazan, 1998; Penke & Krause, 2004; Zukowski, 2005), and core aspects of the syntax and semantics of spatial language (Landau, 2011, Landau and Hoffman, 2012). …”