Different letter-processing strategies in diagnostic subgroups of developmental dyslexia also occur in a transparent orthography: Reply to a commentary by Spinelli et al.

Abstract

The article was motivated by a commentary of Spinelli et al. (2010) Spinelli, D. , Brizzolara, D. , De Luca, M. , Gasperini, F. , Martelli, M. and Zoccolotti, P. 2010. Subtypes of developmental dyslexia in transparent orthographies: A comment on Lachmann and van Leeuwen (2008). Cognitive Neuropsychology, 26: 752–758. [Google Scholar] , who commented on our experimental study with dyslexic children (Lachmann & van Leeuwen, 2008). They questioned the unusually large reversed lexicality effect we reported for three of our dyslexic children for which word reading times were considerably longer than nonword reading times. We argued that, in principle, in a transparent orthography, such as German, children exist who have significant problems in word reading, but for whom nonword reading is normal. The extreme reversed lexically effect, however, may not be representative for the dyslexic population. Since we do not want to give the impression that our results were based on these three participants, we reran analyses on reaction times presented in Lachmann and van Leeuwen, this time excluding the data from the three individuals. Results were replicated. The constructive criticism has helped put both the diagnostics and our experimental results on even firmer ground. Both yield a consistent interpretation, in which two subgroups of dyslexics can be distinguished: one with generic activation problems; the other with a specific problem in phoneme-grapheme conversion.