A case of semantic aphasia (Luria) with difficulty in understanding logico-grammatical relations was reported. The patient, 28-year-old left-handed woman, was injured in a traffic accident in the right parieto-occipital area. After fifteen months of recuperation, she was noticed to suffer from mild word-finding difficulty, agraphia, acalculia, minimum right-left discrimination deficit and disturbance of logico-grammatical operations, in the context of excellent verbal I. Q. on the WAIS Test and almost normal performance on the Token Test and other syntax tests. Spatial organization and representation ability showed some decline. Difficulty of understanding logico-grammatical relations became apparent mostly in the case of double comparative constructions or triple constructions which required the subject, for instance, to draw a circle to the right of a triangle and to the left of a square. To decipher these logico-grammatical constructions according to grammatical rules, it seemed neccessary for the subject to consider the elements of the sentence simultaneously in order to know which is the main element acting as the basic point of judgment, to represent mentally the relation of elements as a spatial constellation, and to reverse mentally the word order in the sentence. It was difficult for the patient to meet these requirements.
