NEURASTHENIA: (noun) Psychiatry (not in technical use) nervous debility and exhaustion occurring in the absence of objective causes or lesions; nervous exhaustion.
The Dance of Life (1900)
A life in boundless pursuit of pleasure makes one blasé because it agitates the nerves to their strongest reactivity for such a long time that they finally cease to react at all. In the same way, through the rapidity and contradictoriness of their changes, more harmless impressions force such violent responses, tearing the nerves so brutally hither and thither that their last reserves of strength are spent; and if one remains in the same milieu they have no time to gather new strength. An incapacity thus emerges to react to new sensations with the appropriate energy. This constitutes that blasé attitude which, in fact, every metropolitan child shows when compared with children of quieter and less changeable milieus. . . .
In the blasé attitude the concentration of men and things stimulate the nervous system of the individual to its highest achievement so that it attains its peak. Through the mere quantitative intensification of the same conditioning factors this achievement is transformed into its opposite and appears in the peculiar adjustment of the blasé attitude. In this phenomenon the nerves find in the refusal to react to their stimulation the last possibility of accommodating to the contents and forms of metropolitan life. The self-preservation of certain personalities is brought at the price of devaluating the whole objective world, a devaluation which in the end unavoidably drags one’s own personality down into a feeling of the same worthlessness.
The Metropolis and Mental Life (1903)
It is impossible to say just what I mean!
But as if a magic lantern threw the nerves in patterns on a screen.
— T. S. Eliot
“The Love Song of J. Alfred Prufrock” (1920)