In the event of extensive tumour formation and when the growth is associated with tract degeneration, the deep reflexes will be increased on the contralateral side, with well-marked extensor plantar response.
(C) To the post-central, angular, and marginal convolutions.
Attacks of focal epilepsy are frequently observed when the tumour occupies the post-central convolution, such developments being probably dependent on forward pressure effects. These epileptiform attacks, however, are almost invariably preceded by some sensory auræ. Furthermore, the fits will usually be followed by ‘some degree of anæsthesia or analgesia, a loss of tactile sensation over half the body, affecting mostly the hand and foot, with loss of power and astereognosis (inability to recognize the form and consistency, and to name objects placed in the affected hand)’ (Beevor).
When situated in the left angular gyrus, word-blindness may result—inability to appreciate the meaning of written words, &c.
When the tumour presses on the optic radiation, hemianopia results, with ipsolateral temporal and contralateral nasal blindness.
(D) To the temporo-sphenoidal lobe.
When the tumour occupies the anterior part of the temporo-sphenoidal lobe, more especially when it is situated on the internal aspect of that lobe, the degree of optic neuritis is intense. Perversion or loss of smell may be noticed—a symptom of difficult determination on account of the general condition of the patient.
As the result of pressure exercised on the optic tracts hemianopia—with hemianopic pupillary reaction (the pupil not reacting to light)—may be observed. Pupillary reactions, however, are complicated by possible paralysis of the third nerve.
Some weakness of the face muscles on the contralateral side is a fairly constant symptom, presumably dependent on the upward pressure exercised on the lower motor areas.
A tumour involving the more posterior and central portions of the lobe may bring about a certain degree of word-deafness, whilst objects may be incorrectly named or named with difficulty, the patient being more or less aware of his mistakes and evidencing considerable annoyance of the same.