234 REPORTS ON INVi:STlGATlONS AND PROJECTS. 



PSYCHOLOGY. 



Farrar, Ckfence B*, Sheppard and Enoch Pratt Hospital, Towson, P. O., 

 Mar3dand. Grant No. 350. Experimeyital studies on stnichcre andf2t7ic- 

 tions of the cerebral cortex, its histopathology and physiological psychology. 

 (For previous report see Year Book No. 4, p. 263.) $1,000. 



An experimental study on the reparatory activities of the cortex cerebri 

 was delayed in publication and is now in press (Histologische u. histopath- 

 ologische Arbeiten iiber die Grosshirnrinde, Jena, Fischer). Porous foreign 

 bodies were introduced into the gray cortex of rabbits under aseptic condi- 

 tions and the reparatory changes observed from the sixth hour to the end 

 of the fourth week. 



The study furnishes interesting information as to the mutual relations of 

 ectodermal, mesodermal, and hematogenous elements in the cortex cerebri, 

 as well as concerning the genesis of blood-vessels and the fibrillar substances 

 in their walls. 



A second study, not yet published, concerns the development of the 

 pia-arachnoid. A complete series of chick embryos was used, beginning 

 with the earliest stage of incubation. The arachnoid is seen to be in no 

 sense a separate membrane. The pia and arachnoid are one and represent, 

 respectively, a highly vascularized and poorly vascularized inner and outer 

 portion of an identical tissue. The only lymph cavities discovered are 

 the arachnoidal spaces themselves and the intra- adventitial spaces of the 

 blood-vessels. 



On the clinico-psychologic side the wards of the Sheppard and Enoch 

 Pratt Hospital have still been drawn upon for material. The object has 

 been to give extended study to individuals and small groups of patients, 

 which are then carefully analyzed and compared. In this way it is hoped 

 to contribute a little perhaps to the possibilities of differentiation in mental 

 diseases. In connection with the course in clinical psychiatry in the Johns 

 Hopkins University the publication has been commenced of a series of type 

 biographies, presenting as completely as possible the clinical course and 

 psychologic analysis of illustrative mental cases. The first three histories 

 have been completed : (I) Dementia pracox ; (II) Depressio affectus ; (III) 

 Depressio psychomotoria, appearing, respectively, in the American Journal 

 of Insanit}' for April, July, and October, 1906. 



The group of devolutional psychoses has also been made the subject of 

 special study and certain provisional subtypes differentiated. At the invi- 

 tation of the British Medical Association a paper was presented on this sub- 

 ject at the Toronto meeting, August, 1906, and was published in the 

 British Medical Journal (September 29) and in the Edinburgh Review of 

 Neurology and Psychiatry. 



