In 1810 Gall published the neuroanatomist's manual Anatomie, correlating variations in cha

In 1810 Gall published the neuroanatomist's manual Anatomie,

correlating variations in character with variations in external, craniological

signs, an approach that depended on three critical assumptions: that the size

and shape of the cranium reflected the size and shape of the underlying portions

(5) of the cerebrum, that mental abilities were innate and fixed, and that the

relative level of development of an innate ability was a reflection of the

inherited size of its cerebral organ. On these assumptions, an observed

correspondence between a particularly well-developed ability and a particularly

prominent area of the cranium could be interpreted as evidence of the functional

(10) localization of that ability in the correlative portion of the cerebrum.

Gall's approach was abandoned in favor of experiment, his conception of

fixed, innate faculties replaced by a dynamic, evolutionary view of mental

development, and his pivotal assumption concerning the relationship of brain to

cranial conformation rejected, but we cannot overestimate his importance in

(15) linking brain activity to specific cerebral anatomy. Gall's assumptions may have

been flawed, but not his scientific logic or rigorous empiricism. In postulating a

set of innate, mental traits inherited through the cerebral organ, Gall admitted

differences in aptitude among individuals and between species and thus deviated

from the tabula rasa view of Condillac.

(20) Even Gall's opponent, Flourens, was willing to admit that it was Gall who

established that the brain serves as the organ of mind. In other respects,

however, Flourens was highly critical of Gall, and soon provided the first

experimental demonstration of localization of function in the brain by employing

ablation to localize a motor center in the front of the brain and motor

(25) coordination in its rear. Although his treatment of sensation was still rather

confused, Flourens articulated a clear distinction between sensation and

perception and localized sensory function within the brain. But with respect to

the cerebrum, a successive slicing through the brain hemispheres produced

diffuse damage to all of the higher mental functions—to perception, intellect,

(30) and will—with the amount of damage varying only with the extent and not the

location of the lesion. Flourens thus concluded that while sensory-motor

functions are differentiated and localized sub-cortically, higher mental functions

such as perception, volition, and intellect are spread throughout the cerebrum,

operating together with the entire cerebrum functioning in a unitary fashion as

(35) their exclusive seat.

As Gall himself observed, ablation was not a method well-suited to the

discovery of cortical localization. Joined to a strong philosophical belief in a

unitary soul and an indivisible mind and an uncritical willingness to generalize

results from lower organisms to humans, Flourens's results led him to

(40) challenge Gall's efforts at localization and to formulate a theory of cerebral

homogeneity wherein, the cerebrum was the organ of a unitary mind which

could not be functionally differentiated to the extent Gall suggested.

The primary purpose of the passage is to

A．provide a biographical account of the experimental careers of two prominent neuroanatomists

B．examine the correlation between brain activity and consciousness from a neuroanatomical point of view

C．probe the relationship between philosophical views concerning the existence of the unitary soul and attempts to map the brain

D．compare the successes and failures of two different experimental methods in neuroanatomy

E．explore the genesis and evolution of early neuroanatomical theory of the localization of cognitive function