As effects of excitement may be noted—(a) those which are transitory, occurring during the excitement, and (b) those which persist. As transitory effects there may be an apparently general hypermnesia, in which there is a marked freshening of all memories, or there may be a selective hypermnesia, where certain rather narrow lines of association are followed. The lasting effects may be hypermnesia, hypomnesia, or total amnesia for events experienced during the excitement. The following lasting effects may also be noted upon experiences that have occurred before the emotion: (1) The well-known retro-active amnesia; (2) The opposite, retro-active hypermnesia to which little attention has formerly been paid; (3) a combination of both these effects; for the same person the stretch preceding the critical event may show vivid recollections followed by a period of utter blank. The retro-active hypermnesia in the author's cases rarely goes beyond the events of the day preceding the excitement. It occurred in 25 out of 225 cases. The antecedent events are unusually vivid—more vivid than any other of the patients' memories. The vividness is not confined to visual images, although these are more frequent; sounds, the mood, the general state of the mind may be clearly represented. There is some indication that women experience it more frequently than men. In some cases the effect has come at some crisis at early childhood, in others at a later date. The quality of the emotion seems of less importance than the intensity of the shock. Fear, or fearless surprise, or pleasurable surprise may be the cause. If the intensity be exceeded the experiences connected with it are in some degree suppressed; while if it be not reached the experiences are lost probably by a mere failure to gather up the events into the mesh of interest. Emotion facilitates the recall of whatever is noticed during the excitement, and it seems probable that memory images may be treated by the emotional onrush in the same way as perceptive images. The experiences of the preceding day, however, probably do not exist as actual images at the time of the emotion but as psycho-physical dispositions or traces, so that where there is retro-active hypermnesia the emotion would seem to have the power to strengthen these dispositions and the connections by which they may be called into life. The author gives illustrative cases.