324 
Gall. If each of these areas, histologically 
distinct from one another, has an individ- 
ual function distinct from the functions 
of the other areas, we should also have a 
similar number of mental functions or 
faculties to correlate with them. Unfor- 
tunately for our purpose, the histologists 
have not attempted to give us the mental 
correlates of all the anatomically distinct 
areas, although in a few cases the anatom- 
ical reasoning and connections have led to 
certain psychological suppositions. It is in 
this way that we must account for the 
psychic areas of Campbell, and for some 
of the other psychological localizations 
which have been made. 
An example of this anatomical reasoning 
is that of Campbell regarding the distribu- 
tion of the sensory areas. In areas which 
were believed, because of the physiological 
and clinical evidence, to have sensory func- 
tions, Campbell observed that certain fibers 
“‘pursue a curious oblique course’’ differ- 
ent from other fibers in other neighboring 
areas. On the basis of this fact Campbell 
constructed other sensory areas, these lat- 
ter areas being endowed by him with men- 
tal (7. e., sensory) functions because in this 
one particular they had an appearance 
similar to that in supposedly known sen- 
sory fields. It did not appear to make any 
difference that these areas might have other 
well-marked differences. The main ana- 
tomical point is that these oblique fibers 
were discovered in different regions, and 
the important psychological point is that 
these minor similarities have been inter- 
preted as indications of similarity of func- 
tion of a mental order. In this case, Gall 
has been surpassed, and his phrenological 
reasoning outstripped. 
The designation by Campbell of psychic 
areas, surrounding the so-cajled sensory 
areas, are interpretations of a phrenolog- 
ical nature of a supposed functional con- 
SCIENCE 
[N.S. Vou. XXXV. No. 896 
nection of the primary receptive areas with 
these and of a relation of these areas to 
mental processes. In this there is a dis- 
tinct psychological interpretation that the 
nervous impulses which start from the 
sense organs reach a part of the cerebral 
cortex and give rise to sensations, and that 
other nerve currents are sent to neighbor- 
ing areas and give rise to perceptions. 
Let us glance for a moment at the cor- 
tical area posterior to the fissure of Ro- 
lando. Campbell divided this region into | 
two distinct zones (the postcentral and the 
intermediate postcentral) which are be- 
lieved to be concerned with the afferent 
impulses from the skin and the underlying 
tissues. The zone bordering on the fissure, 
the posteentral, Campbell designates as 
“‘sensory,’? and that adjoining the first 
area ‘‘perceptive.’’ In the first area the 
sensations of touch, of temperature, of pain 
and of movement are localized, and in the 
adjoining area (the intermediate postcen- 
tral) there are the psychic functions of 
localization of touches and also the so- 
called stereognostic sense. If we consider 
only the postcentral sensory area of Camp- 
bell, we might ask: Why should the same 
brain area be concerned with such ‘unlike’ 
sensations as those which he attributes 
to it? By histological-phrenological rea- 
soning we should have four, or even 
eight, distinct areas. Even though the 
eross sense organs have been differentiated, 
taste and smell, as sensations, are as much 
alike as are touch and pain and tempera- 
ture and we might on anatomical grounds, 
if we closely follow Campbell, expect them 
to have seats in the same area. The ob- 
servations of Cushing upon the effects of: 
excitation of the postcentral area in con- 
scious patients have not helped this at- 
tempt at a definite mental localization, and, 
in fact, they are decidedly opposed to it. 
The motor area of the brain has been the 
