The name is absent

60 The Rice Institute Pamphlet

The earliest studies on animal behavior involving surgical
removal of frontal lobe tissues were done without clear-cut
anatomical or behavioral criteria for evaluation of the results.
Bianchi’s (1895) work on monkeys and dogs is typical. The
location and amount of tissue to be removed was essentially
uncontrolled, varying from animal to animal. It was therefore
difficult to compare the results from different operations. The
only data on the effects of the surgical procedures were in
the form of anecodotal reports of changes in behavior or
“psychical condition” manifested in the laboratory setting.
Again it was impossible to compare the results from subject
to subject. Bianchi, working with these limitations, con-
cluded that operations on the frontal lobes did influence the
intellectual functions of his animals. Others working at the
same time with similar limitations arrived at the opposite
conclusion (cf. Horsley & Schafer, 1888).

Beginning about 1900, Franz (1907) began a series of
studies on monkeys and cats designed to specify more pre-
cisely the cortical lesions produced and to measure the effects
of the operations on specific habits. He trained the animals
to open puzzle boxes; then, after systematically varying the
amount and location of cortical tissue removed for different
animals, he tested them again on the original problems. Al-
though the results were not wholly consistent, Franz felt that
his data warranted the conclusion that destruction of tissue
in the frontal lobes results in the loss of the newly formed
habits which, however, could be relearned. Well established
habits were not affected by the operations.

Subsequent studies have varied both the lesions and the
kinds of tasks required of the animal. Lashley’s (1929) work
on the performance of rats in mazes cited above led him to
favor a quantitative hypothesis: the amount of tissue re-
moved is relevant, but not. its location. Jacobsen’s (1931)

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