Abstract
The experiments which we here record were performed during the preceding winter and spring in the physiological laboratory of University College, but their formal publication has been hitherto deferred because we were desirous of keeping some of the animals in which the lesions had been established under observation during several months, in order that any modification which that lapse of time might produce in the symptoms should be duly recorded. But, although not hitherto published, several of the cases, while still under such observation, have been brought before the notice of both the Physiological and the Neurological Society of London, and have been examined at different times by various persons interested in the subject of cerebral localisation, besides being familiar to the regular workers in the laboratory. In this way we have repeatedly had the opportunity of showing most of the symptoms which we are about to record, nor have we inserted any detail as to the accuracy of which there could, to an unbiased mind, be the slightest doubt. All our experiments have been performed with the view of establishing certain lesions, uni- or bi-lateral, embracing definite areas of the cerebral cortex; and they have been confined, or nearly so, to the occipital and temporal lobes. In the performance of the operations strict antiseptic precautions were employed, the dressings being fixed by a collodion cap. On the fourth or fifth day after the operation this cap and the dressings were removed, and in every case the wound was found to be completely closed, the edges of the skin being closely united, no sign of meningitis nor of any septic mischief being at any time perceptible. In one exceptional case, however, in which the antiseptic precautions had, from over confidence, been relaxed, the asepticism was incomplete, and sloughing of the skin over the seat of operation resulted, so that the animal had to be killed within a few days of the performance of the operation. This case will be mentioned in due course.