That paramnesia is a fatigue product--even though often a product of nervous hyperaesthesia--is indicated by the statements of many who have described it. Anjel long ago emphasised this fatigue, and Bonatelli, also at an early period, found that illusions of memory were specially liable to occur in states of unusual nervous irritability. During recent years this characteristic of paramnesia has been more and more frequently recognised. Bernard Leroy, who devoted a lengthy and important Paris thesis to pseudo-reminiscence,[228] showed that a certain proportion of cases indicated the presence of fatigue or distraction. Heymans found that it was in the evening, when his subjects were in a passive condition, tired, exhausted, or engaged in uncongenial work, that they were most liable to the experience.[229] Féré brought forward a case in which, as he pointed out, pseudo-reminiscence in a healthy man, convalescent from influenza, was associated with fatigue and disappeared with it.[230] Dromard and Albès declare that pseudo-reminiscence is 'a phenomenon of exhaustion,' and one of them makes the significant statement: 'I become more easily the prey of this illusion when, by chance and without thinking of it, I simultaneously apply my attention to an external object and an internal thought.'[231] Dugas, again, considers that all the various forms of paramnesia have 'one common character, which is that they occur as the result of prolonged or intense fatigue';[232] he adds that most of the cases of paramnesia he has noted in young people during fifteen years coincided with periods of anaemia and nervous weakness. It is not, however, necessary to believe that fatigue, in the ordinary sense of the word, whether physical or mental, is the invariable accompaniment of paramnesia. If it is the presence of a condition resembling that of sleep or the hypnagogic state which predisposes to the experience, that condition may be produced by other circumstances. Distraction, excited hyperaesthesia simulating increased power, and various chronic psychic states due to a highly-strung or over-strained nervous system may all tend in the same direction, even though no sense of exhaustion is felt.[233] This is doubtless why it is that so many poets, novelists, and other men of strenuous intellectual aptitude are liable to this experience.