[A psycholinguistic study in a patient with echolalia].

Language is often impaired in patients with a primary degenerative dementia syndrome. Severe dementia may even lead to mutism, a condition in which the person does not produce any spontaneous speech, despite preservation of consciousness. The question is if there are any language abilities left in patients who do not speak. In this single case-study the echolalic behaviour of a patient with severe dementia and mixed transcortical aphasia (or isolation of the speech area) was analysed by means of special linguistic tasks. In repeating sentences violating number agreement, the patient spontaneously corrected the pronoun, the noun or the verb. Furthermore, her verbal output during repetition tasks was highly constrained to lexically acceptable Dutch nouns. Despite extremely poor comprehension, this patient did not repeat verbal utterances in a parrot-like fashion. There are not many reports in the literature of patients who develop a mixed transcortical aphasia as a consequence of primary degenerative dementia. A comparable case was described by H. Whitaker. Single case-studies, such as these, are essential to our insight into the course of language breakdown in senile dementia. The preserved repetition ability of this patient demonstrates the robustness of the articulatory loop system, even if there is a severe comprehension deficit.