Mental fatigue : a comprehensive exposition of the nature of mental fatigue, of the methods of its measurement and of their results, with special reference to the problems of instruction / by Dr. Max Offner tr. from the German by Guy Montrose Whipple.
- Offner, Max, 1864-1932.
- Date:
- 1911
Licence: Public Domain Mark
Credit: Mental fatigue : a comprehensive exposition of the nature of mental fatigue, of the methods of its measurement and of their results, with special reference to the problems of instruction / by Dr. Max Offner tr. from the German by Guy Montrose Whipple. Source: Wellcome Collection.
Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.
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![cess are they not, as a matter of fact, concerned! But no one would think of calling such psychophysi- cal investigations physiological, even though they were first attacked by physiologists. So, too, in this case, it was a physiologist, E. H. Weber of Gottingen, who discovered long ago (1834) that the shortest distance at which the contact of two points is still felt as separate, i. e., as the contact of two cutaneous points, that the spatial limen, as the distance was named by Fechner,* varies at different regions of the body, and on different persons in the same region. The relative values of the spatial limen for different regions are, however, approximately constant for all persons. Now, these liminal values are increased by physical work. Griesbach {Energetik, 1895) appears to have been the first to observe that, in a given individual, the limen is also increased by strenuous mental work. He found—and Eulenberg soon after confirmed the observation on himself {Hyg, Rundschau, VIII, 600) —that two closely approximated blunt compass points applied gently to the skin at the same moment are, as a rule, after fatiguing work, perceived as one point, whereas they had been still perceived as two before the work was begun. In general, the increase of f atignie goes hand in hand with the increase of the spatial limen, save that, under conditions of exces- sive fatigue, combined with mental depression and feelings of discomfort, there appears, for reasons as *0. Ktilpe {G-rundriss d. Pspch., 38 f., 350 ff. [see English trans- lation, Outlines of Psychology, pp. 36 f. and 337 ff.]) and others have shown that this determination does not afford a liminal value in the strict sense of modern psychophysics.](https://iiif.wellcomecollection.org/image/b21211632_0044.jp2/full/800%2C/0/default.jpg)
