Finnish compound structure: experiments with a morphologically impaired patient.

The present study addresses two major aspects of compound processing, namely the issues of access code and structural effects (headedness), with an extensively studied deep dyslexic patient, HH, who has previously been shown to suffer from morphological impairment. In oral reading of compounds, HH preserves their morphological structure and, at the same time, shows additional processing load in increased errors compared to monomorphemic and derived words. Our data suggest that semantically transparent Finnish compounds are decomposed into their constituents at the level of lexical access. Furthermore, there is a processing asymmetry between the constituents, since several qualitative features of HH's reading performance suggest that it is the first constituent which primarily serves as the initial access code.