Through the kind recommendation of the late Dr. W. H. R. Rivers I was appointed by the Medical Research Council to undertake a study of the psychoneurotic aspects of miners' nystagmus for six months in 1920–21, and subsequently given permission to publish my results.

Encephalitis lethargica, or epidemic encephalitis as it is now usually called, is becoming more generally recognized throughout the world, and while diagnosis is usually easy in those cases with a clear history, and who show the “encephalitic syndrome” to a marked degree, much confusion has arisen in the case of some patients who have shown clinical features which have led observers to arrive at a diagnosis of this disease when later investigations have shown that this conclusion has not been a correct one.

The presence of cholesterol in the cerebro-spinal fluid has been the subject of investigation by various observers. The following communication is based on a series of observations conducted at the Pathological Laboratory of the Maudsley Hospital, on specimens of cerebro-spinal fluid obtained from patients in the mental hospitals of the London County Council.

A defence of insanity is frequently raised in answer to a serious criminal charge if the facts of the case clearly indicate the guilt of the accused. From time to time in such circumstances the jury are invited to exculpate the prisoner on the ground that the act was committed during a condition of epileptic automatism.

(This communication forms part of a Report to the Medical Research Council.)

There is in the mind a mass of past experiences which cannot be readily remembered. We also know that while the individual is aware of some of the processes of elaboration going on in his mind, there are other mental processes which elude his observation. Both forgotten experiences and unrealized mental processes constitute material of which the individual was said to be “not personally conscious.” The modern psychologist says the forgotten memories and the hidden mental processes are in the unconscious or subconscious mind, a stratum of the mind below the threshold of personal consciousness. He bases this statement on the conception that while the mind is a complete entity, it is so disposed that while the contents of one portion can be at once investigated by the individual, the rest is not so easily explored. The accessible portion is called the conscious mind, the rest the unconscious. Dr. G. Stanley Hall compared the mind to an iceberg, floating in the ocean with one-ninth visible above the water and eight-ninths below, the visible ninth corresponding to the conscious mind, and the larger submerged portion to the unconscious mind. Before the time of Freud there was no satisfactory method of exploring the unconscious. Freud, when dealing with neurotic and mental patients, was dissatisfied with the results obtained by hypnotism. But he noticed that some experienced relief, and also improved, when encouraged to talk frankly about their anxieties and difficulties. He worked out a method of exploring the unconscious mind, called psycho-analysis, founded on the theory that dreams are not accidental or meaningless; interpreted by the method of free association, they constitute the royal road to the unconscious mind. Free association means that when the analysand is asked of what a particular item in the dream makes him think, he gives the idea that first occurs to him, however far-fetched or absurd it may seem, and then allows one idea to call up others without let or hindrance.

In connection with the malarial treatment of general paralysis of the insanein thishospital, we have endeavouredto producea secondseriesof malarialrigorsin such casesas had not shown sufficient mental or physical benefit after a first infection terminated six or more months ago.

The incubation period of naturally acquired benign tertian malaria is usually given as being from two to three weeks. Thus James (1920) states that the period is usually from 14 to 18 days, Stitt (1922) from 14 days, Acton, cited by Castellani and Chalmer (1919), 6 to 21 days, and Castellani and Chalmers (1919) from 9 to 12 days.