Higher Cortical Functions in Man

intellectual activity may be largely preserved In lesions oCthefeft temporal region. However, the patient with a disturbance of the phonemic and conceptual structure of the speech processes always experiences considerable difficulty notwithstanding the adequate preservation of the ability to engage in certain forms of abstract intellectual activity, when he attempts to carry out systematic, successive operations with relationships requiring the constant participation of speech associations as mediators. In such circumstances the ability to discriminate between relationships becomes manifestly inadequate and the patient'S intellectual operations begin to suffer. The intellectual defects of a patient with temporal aphasia become apparent in nonspeech operations in which an essential part of the process entails the use of systems of speech associations retained in the memory. For instance, a patient who could still sort out a series of pictures telling a story, provided he was allowed to mix them up himself, found the process very difficult if he was not allowed to touch the pictures and was asked to put them in the proper order as indicated by the appropriate numbers (Ombredane, 1951). These patients experience similar difficulties with series of geometrical operations. The defects were found to be particularly serious when such patients attempted to do mental arithmetical calculations. They had no difficulty in grasping numerical relationships but, although usually preserving the general plan of the necessary actions, they became helpless when given problems requiring a series of successive operations with some of the results to be kept in mind. An attempt to assist the process by allowing them to speak out loud was unsuccessful, and without the support of a well-established and differentiated system of word associations it was seriously impaired. It should be noted that the operations of discursive intellectual activity, which are wholly dependent on speech, for example, the solution of logical problems as in Burt's tests on the establishment of multiple relationships (Part III, Section 8E), remained completely beyond these patients' ability. They • Among our patients was a bookkeeper with a severe form of sensory aphasia who could still draw up the annual balance sheet in spite of severe disturbances of speech and although he was unable to remember the names of his subordinates and used to refer to them incorrectly.