are only realized by those that follow. Not with impunity, either, can we congeal into distinct and independent things the fluidity of a continuous undivided process. This symbolism may indeed suffice as long as it is strictly limited to the facts which have served to invent it: but each new fact will force us to complicate our diagram, to insert new stations along the line of the movement; and yet all these stations laid side by side will never be able to reconstitute the movement itself.
Nothing is more instructive, in this regard, than the history of the diagrams of sensory aphasia.Illustrations from the history of the theories of aphasia. In the early period, marked by the work of Charcot,[1] Broadbent,[2] Kussmaul[3] and Lichtheim,[4] the theorists confined themselves to the hypothesis of an 'ideational centre' linked by transcortical paths to the various speech centres. But, as the analysis of cases was pushed further, this centre for ideas receded and finally disappeared. For, while the physiology of the brain was more and more successful in localizing sensations and movements, but never ideas, the diversity of sensory aphasias obliged clinicians to break up
- ↑ Bernard, De l'aphasie, p. 37.
- ↑ Broadbent, A Case of Peculiar Affection of Speech (Brain, 1879, p. 494).
- ↑ Kussmaul, Die Störungen der Sprache. Leipzig, 1877, p. 182.
- ↑ Lichtheim, On Aphasia (Brain, 1885). Yet we must note the fact that Wernicke, the first to study sensory aphasia methodically, was able to do without a centre for concepts (Der aphasische Symptomencomplex. Breslau, 1874).