PATHOLOGICAL HABITS 237 



time to set up a habit of heightened activity on the part of the 

 secreting cells, so that when the irritant disappeared and was no 

 longer in action, the congestion remained, and with it the cells 

 continued to secrete abundantly. 



A few months ago my colleagues, Drs. Birkett and Meakins, 

 contributed a paper, " Vaccine Treatment in Chronic Inflamma- 

 tory Disease of the Accessory Sinuses of the Nose," to a most 

 interesting discussion on " Vaccine Therapy " at the Triennial 

 Congress of American Physicians and Surgeons at Washington. 

 They reported a short series of cases in which from the sinuses 

 a growth of one or other pyogenic organism was obtained prior 

 to treatment with vaccines, and in which, as the result of the 

 treatment, the discharge became wholly sterile. But in the 

 majority of these cases, while the character of the fluid changed 

 under treatment from a mucopurulent to a purely mucoid fluid, 

 the discharge, it is noted, had continued for months, with all the 

 distressing symptoms of hypersecretion and retention. To 

 explain this, Dr. Meakins calls attention, first, to the chronic 

 thickening of the submucous layer of the lining of the sinuses, 

 as the result of continued inflammation ; and, secondly, to a 

 partial closure of the ostia by the swollen mucous membrane 

 inducing defective drainage ; thirdly, he comes to the same 

 conclusion that I had reached in the case just described, namely, 

 that through repeated stimuli (at first bacterial) hypersecretion 

 has been set up, which after a time has become a true habit, 

 independent of bacteria, as evidenced by its perpetuation after 

 the cavity has been practically sterilized. 



As I have already hinted, we are all so familiar with the 

 establishment of nervous habits, with the development of habit 

 tics and those graver habits of lack of co-ordination, and appar- 

 ently of arrest of active communication between various centres, 

 which would seem to be the basis of hysteria, that I must not 

 here tire you with an enumeration thereof. It is well recognized 

 that it is easier for nervous stimuli of different orders to travel 

 along well-worn paths, and that thus there may be established 

 a condition in which a minimal afferent impulse, travelling 

 without interruption along a particular path, is sufficient to set 

 in action first one and then another of a group of co-ordinated 

 centres whereby a minimal stimulus may eventually produce 

 a maximal result ; per contra, the act of inhibition or arrest of 



