ON THE FUNCTIONS OF THE CEREBRUM 339 



localisation. On the other hand, from the aspect of cerebral 

 function, they are throughout constructive in tendency. From 

 both points of view, however, they are in accord with the results 

 of recent histological and psycho-physiological research. 



From the aspect of cortical localisation, Broca's speech-centre 

 is disrated by Marie. This is a conclusion for which modern 

 histological investigations have already prepared the way. On 

 referring to the maps of Brodmann and of Campbell, the reader 

 will see that both these observers indicate a histological type 

 of cortex (" intermediate precentral " of Campbell, and 44 of 

 Brodmann) in the posterior third of the inferior frontal con- 

 volution, which differs from that of the psychomotor area. 

 Campbell, in fact, whose monograph appeared before the publi- 

 cation of the papers of Marie, protested against the assumption 

 that a lesion of the area of Broca is the essential factor in the 

 production of motor aphasia on the ground that this region is 

 histologically undifferentiable from, and is included in, his " inter- 

 mediate precentral " area. He cites two cases of destruction of 

 Broca's area in which permanent motor aphasia existed. In a 

 third case, however, in which the area of destruction is even 

 more extensive, the patient, though twelve years previously he had 

 suffered from complete but transitory aphasia, exhibited no speech 

 defect whatever during the whole of this period and right up to 

 the time of his death. 



The more detailed map of Brodmann, it is true, indicates a 

 special histological type (No. 44) in Broca's area, but this type 

 does not possess " motor " characteristics, arid is indeed separated 

 from the psychomotor or Betz-cell region (No. 4) by an area (No. 6) 

 which, though less in extent, is similar in distribution to the " inter- 

 mediate precentral " area of Campbell. K, as Campbell suggests, 

 this last area is " specially designed for the control of skilled move- 

 ments of an associated kind," his argument re motor aphasia is 

 strengthened by the exclusion from this " intermediate precentral " 

 region, by Brodmann, of Broca's area. 



The views of Marie will now be considered with regard to their 

 bearing on our knowledge of the functions of the cerebrum. Marie 

 states that the essential feature of aphasia is the existence of 

 intellectual impairment, although the patient may appear, from 

 the aspect of every-day life, to possess normal mental faculties. 

 To put this opinion into other words, Marie in effect states that 



