304 RESEARCHES ON CORTICAL LOCALISATION AND 



to read. He is of the opinion that the only region of the brain which 

 can be regarded as purely associational in function is the prefrontal 

 area, which is generally acknowledged to possess no fibres of pro- 

 jection ; and, excluding the language zone, he considers that the 

 whole post- and infra -Rolandic portion of the cortex cerebri is 

 perceptive in function. " One can symbolise the cerebral mantle 

 as a state with a representative system a parliament and govern- 

 ment. The mantellar parliament would be constituted by the 

 perceptive zones. . . . The central government would be repre- 

 sented by the frontal lobes." (Textbook, 1906, p. 172.) Bianchi, 

 in other words, denies that the post- and infra -Rolandic parts of 

 the cerebrum can be subdivided into areas of projection and zones 

 of association. 



As a general statement it may be remarked that the conclusions 

 of Flechsig, in their essential features, have been widely accepted, 

 and that, whilst the projection areas, as has been already pointed 

 out, probably occupy neither the identical position nor the same 

 extent of cortex in the adult brain that they do in the foetus and 

 infant, it may be assumed that a great parieto-temporal centre 

 of association exists posteriorly, and a more complex prefrontal 

 centre of association anteriorly, the insular and precuneal centres 

 being less complex in type, and probably of less importance, than 

 either of the former. 



After this introduction to the question in its more general 

 aspects, the subject of cortical localisation by histological methods 

 will now be considered in detail. 



The first important paper on cortical localisation was that of 

 Bevan Lewis and Henry Clarke, published in 18J8, on the cortical 

 localisation of the motor area of the brain. This communication, 

 which localised the motor area in front of the furrow of Rolando, 

 attracted little attention owing to the fact that the conclusions 

 contained in it were opposed to the results of the numerous 

 physiological experiments which, during the last two decades of 

 the nineteenth century, largely monopolised the field of inquiry 

 into the functions of the cerebrum. The observations of Lewis 

 and Clarke have, however, at last obtained complete if belated 

 recognition in consequence of the experimental work of Sherrington 

 and Griinbaum, recently confirmed by Oscar Vogt, and the his- 

 tological researches of Campbell and of Brodmann. It is an 

 interesting and in many respects a fortunate fact that the experi- 



