re, and by this is meant the portion of brain which receives
impressions from each half of the field of vision, is situated for the most
part on the inner (unseen) surface of the occipital lobe. In front of the
central fissure is situated the motor area, or that region destruction of
which causes paralysis of the muscles moving the structures of the opposite
half of the body. If the situations indicated by black dots be excited by
an interrupted electric current, movements of the limbs, trunk, and face
occur in the precise order shown, from the great toe to the larynx. In
front of this precentral convolution are the three frontal convolutions,
and it would seem that the functions of these convolutions are higher
movements and attention in fixation of the eyes; moreover, in the lowest
frontal region, indicated by fine dots, we have Broca's convolution, which
is associated with motor speech; above at the base of the second middle
frontal convolution is the portion of cortex in which is localised the
function of writing. Taste and smell functions reside in brain cortex only
a small portion of which can be seen, viz. that at the tip of the temporal
lobe.]
Muscles and groups of muscles on the two sides of the body which invariably
act together may thus be innervated from either hemisphere, e.g. the
muscles of the larynx, the trunk, and upper part of the face.
Gall, the founder of the doctrine of Phrenology, wrecked his fame as a
scientist by associating mental faculties with conditions of the skull
instead of conditions of the brain beneath; nevertheless, he deserves the
highest credit for his discoveries and deductions, for he was the first to
point out that that part of the brain with which psychic processes are
connected must be the cerebral hemispheres. He said, if we compare man with
animals we find that the sensory functions of animals are much finer and
more highly developed than in man; in man, on the other hand, we find
intelligence much more highly developed than in animals. Upon comparing the
corresponding anatomical conditions, we see, he said, that in animals the
deeper situated parts of the brain are relatively more developed and the
hemispheres less developed than in man; in man, the hemispheres so surpass
in development those of animals that we can find no analogy. Gall therefore
argued that we must consider the cerebral hemispheres to be the seat of the
higher functions of the mind. We must moreover acknowl
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