ABSTRACT
This chapter presents a review of the Transcortical Aphasias (TA) and a reconceptualisation of linguistic and neuroanatomical findings based on both previous clinical and theoretical studies as well as in modern cognitive and functional neuroimaging studies. The preservation of repetition is unanimously regarded as the key feature of TA, with variable deficits in other language functions (spontaneous speech and auditory comprehension) being also required to establish the taxonomic diagnoses of the transcortical syndromes. Very different mechanisms are possibly operating during the production and reception of language in patients with TA. This might explain the heterogeneity in linguistic features including, for instance, the variable status of repetition (e.g. some transcortical patients can repeat nonwords and long sentences, whereas others can not). Left-hemisphere damaged aphasic patients with either nonfluent or fluent spontaneous speech and variable deficits in auditory comprehension activate the right hemisphere more than the undamaged regions of the left hemisphere during the repetition of words.
