66 The Rice Institute Pamphlet
logical, psychiatric—of the results of bilateral symmetrical re-
movals of tissue in different anatomical areas of the frontal
lobes. None of the patients showed any permanent impair-
ment of function from the operation which could be demon-
strated on an extensive battery of psychological tests. No
loss in memory, learning, or intellectual functions could be
attributed to the operations; instead, gains in recall and
recognition scores were often observed. Impairment of the
ability to abstract or generalize could not be regularly
demonstrated. No permanent changes were noted in intelli-
gence test scores; transient losses were usually regained with-
in four months. The overall evaluation of the Columbia-Grey-
stone Associates is that the frontal lobes do not seem to play
an important role in intellectual functioning of the kind re-
quired for the tests they used.
The lobotomy operation performed in the Boston Psycho-
pathic Hospital studies (Greenblatt & Solomon, 1953) does
not involve removal of tissue from the frontal lobes. Instead,
small holes are bored in the top or side of the head and a
knife used to sever the fibers which connect the frontal lobes
with other areas of the brain. Assessment of changes follow-
ing the operation showed, if anything, improvement in intel-
lectual functioning. Ability to think conceptually or abstractly
and make inferences improved; thinking seemed more con-
trolled and coherent. The changes certainly must be under-
stood in relation to low test scores before the operation and
to the psychiatric status of the patients which may have in-
fluenced those scores. However the improvements might be
explained, it is clear that the operation did not reduce intel-
lectual functioning in any way that the methods of assess-
ment used in this study could identify.
The conclusions reached by Hebb and the staff of the two
projects cited leaves the role of the frontal lobes in intellec-