Introduction Variations in the estimation and judgment of time passage, in the reproduction of intervals, and in the subjective attitude to the flow of time occur in many psychopathological states and in the healthy person from time to time. Schilder8has reviewed the psychopathology of time and noted that the schizophrenic patient may have a disturbance in the subjective feeling of time but not in the perception of time. Aubrey Lewis5noted that alteration of the consciousness of time is a primary alteration and predicted that such alteration would be found as often as it is looked for. In general, there is difficulty in studying quantitatively the estimation of time, and there is a relatively small amount of experimental work in the subject on psychiatric patients. Pieron,7Françis,1and Hoagland2developed the notion that the mechanism of time perception in the human organism depends on the