The Brain and Behavior
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reported that for his monkeys “friendliness and sociability
(are) impaired; . . . their avidity becomes reckless and in-
satiable,” and he spoke of “a dissolution of the psychical per-
sonality” (1895,p. 522). His results contrasted with the nega-
tive findings of HorsIey & Schafer (1888) just as they had for
observations of intellectual processes. Franz (1907) in his
more carefully controlled studies stated that “the emotional
condition of the animal remains the same after as before the
removal of the frontals” (p. 63). However, although Franz
had systematic ways of evaluating the effects of the opera-
tions on habits, his judgments of emotional change were as
anecdotal as those of his predecessors.
Much of the subsequent neurophysiological research on
emotions is associated with the work of Cannon (1929) and
Bard (1928, 19S4a, 1934b, 1950). They began by studying
more carefully the effects on animal behavior resulting from
removal or isolation of the cerebral hemispheres. They ob-
served in their animals a complex rage reaction elicited by
trifling disturbances and distinctive for its intensity and
breadth of expression. This “sham rage” was quite different
from the “pseudaffective” reactions noted by Sherrington
which were more similar to a normal animal’s expressions of
mild anger. Further research led them to identify the hy-
pothalamus, one of the subcortical regions of the central
nervous system, as the mechanism involved in the production
of sham rage. Destruction of tissue which left the hypothala-
mus intact resulted in sham rage; direct stimulation of the
hypothalamus produced the rage reaction; destruction of the
hypothalamus eliminated it. Once the functions of the sub-
cortical center for emotional expression were identified it
became necessary to determine the way in which the cere-
bral cortex itself was involved in the process.
The studies of the hypothalamus suggested that the cortex