The experiments described in this paper were performed in an attempt to elucidate the mechanism of the convulsion following the administration of cardiazol (pentamethylenetetrazol). The paper is divided into four sections—a description of experiments, a résumé of the relevant pharmacology of cardiazol, a discussion and a summary.

All those who have worked with insulin will have been impressed by the great freeing of behaviour that the patients exhibit. It is seen in the hypoglycæmic state, before coma sets in, and as the patient returns to consciousness after interruption of the coma. The degree of this freeing varies directly with the prognosis. In this uninhibited state the anatomy, the very bones of the personality, can be studied, and the physician's observations should be able to establish the main outlines of the pathology of the total personality—the psycho-pathology.

This paper is an attempt to record the experience gained in treating 44 schizophrenics in this hospital with cardiazol from September, 1937, when the treatment was first used, to the middle of April, 1938.

Early Work.

About twelve years ago, apart from mental work, I had occasion to use insulin to some considerable extent for the treatment of diabetes and the preparation of diabetic cases for operation, and acquaintance was thus made with hypoglycæmic shock. Most of us have had that experience. Insulin has been tried more recently in a large field, being used as a remedy in conditions of all sorts, even as a dressing for septic ulcers. But the writer's scope has been more confined, the extent being limited to mental cases.

In 1933 Sakel described the induction of epileptiform convulsions during hypoglycæmia, using camphor and cardiazol. This was not, to my knowledge, followed up systematically until Georgi's work, which started in 1934.

The occurrence of auricular fibrillation in three patients; notes regarding onset, nature and duration of manifestations.

Electro-cardiographic diagnosis, interpretation of and comparison with organic fibrillation.

The onset of heart-block immediately following a convulsion in another patient. Discussion of subsequent course and treatment.

Comment on the significance of these complications in relation to the safety of convulsive therapies.

Observations on blood-pressure in some of the above cases.

The insulin therapy of the psychoses as evolved by Sakel (1) was introduced to Three Counties Hospital 16 months ago. The total number of patients treated and under treatment is 74; 56 have had a full course of the treatment in addition to psychotherapy, and of these, 29 have been discharged and 4 will leave the hospital in the near future. A total number of 3,205 hypoglycæmic comas have been induced up to the present in 4,379 patient insulin days. Serious emergencies arose in only 6 comas. One patient had severe laryngeal spasm, another acute ódema of the lungs, and four delayed return to consciousness. No fatality occurred. Twenty-eight patients had 81 fits in the same number of comas. I shall outline briefly the circumstances which led up to the emergencies met with by myself and some published by other workers in this country, and give the treatment applied.

(1) The “we” means the inner or subjective side of group-experience, expressed grammatically in the first person plural. For instance, the mother giving her child a bath says to it, “We are having a bath now, and then we are going to sleep “, whereas it is only the child who is going through the ceremony.