[Transcortical aphasia and echolalia; problems of speech initiative]

Transcortical aphasia accompanied by echolalia occurs with malacias involving the postero-median part of the frontal lobe which includes the supplementary motor field of Penfield and is nourished by the anterior cerebral artery. The syndrome manifests itself in such cases even in fine detials in the same form as does in Pick's atrophy. The same also holds true for cases in which a tumour involves the region mentioned. Sentences or fragments of sentences are echolalised; tendency to perseveration is very marked. It is hardly, if at all, possible to evaluate the verbal understanding of these patients. Analysis of their behaviour supports the assumption that they have not lost the adaptation to some situations. Echolalia is often associated with forced grasping and other compulsory phenomena. Therefore, it may be interpreted as a sign of disinhibition of the acusticomotor reflex present during the development of the speech. Competition between the intentionality and the appearance of compulsory phenomena greatly depends on the general condition of the patient, particularly on the clarity of consciousness. The integrity of the postero-median part of the frontal lobe is indespensable for a normal reaction by speech to stimuli received from the sensory areas. The influence of the supplementary motor field on speech intention seems to be linked to the dominant hemisphere. In case lesions of the territory of the anterior cerebral artery and the cortico-bulbar neuron system are coexisting in the dominant hemisphere, the speech disturbance shifts to complete motor aphasia. In such cases the pathomechanism is analogous to that of the syndrome of Liepmann, i.e., right-sided hemiparesis with left-sided apraxia. So-called transcortical motor aphasia without echolalia can be caused by loss of stimuli from the sensory fields.