Naming compounds in Alzheimer’s disease

The peculiar pattern of linguistic and cognitive deficits in early Alzheimer’s disease (DAT), whereby memory limitations and failure in semantics prevail over deficits in syntax, makes an interesting contrast with linguistic deficits in classic aphasia categories. The present study compared errors in picture naming of different types of Italian compounds, both in aphasia and in DAT. As in previous studies, in aphasia the knowledge of the compound status seems to be retained vis-à-vis the inability to retrieve the phonological form. This effect is much less evident in DAT. The target compound structure in errors is also preserved in aphasia, while DAT participants seem to compensate for their retrieval failure by overwhelmingly using the most productive structures. Unlike in aphasia, in DAT the retrieval of the second component is more difficult than the retrieval of the first component, probably as an effect of processing overload.