An introduction to experimental psychology / by Charles S. Myers.

  • Charles Samuel Myers
Date:
1911
Catalogue details

Licence: In copyright

Credit: An introduction to experimental psychology / by Charles S. Myers. Source: Wellcome Collection.

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    have hitherto been studying. This deep sensibility consists in sensitiveness to pressure and, when this pressure exceeds a certain limit, in sensitiveness to pain. If only the touch be heavy enough to produce a sensation, it can be localized with remarkable accuracy. The subject can also satisfactorily dis- criminate between the positions of two pressures applied successively to neighbouring spots of the skin. Yet, despite the unchanged power of localization and the unchanged spatial threshold for successive pres- sures, the subject is incapable of distinguishing double pressures when they are made simultaneously, and he is incapable of determining the relative size of different objects successively placed on the skin of the affected area. Let us now study the return of sensitivity in a definite skin-area of a human arm which, for purposes of scientific study, had expressly been made insen- sitive by surgical section of a nerve supplying it. The salient features that marked the process of recovery may be summarised as follows : Forty-three days after the operation the loss of cutaneous pain began to diminish in extent, the boundaries of the painless area retreating, and islets of sensibility to pain making their appearance within the insensitive area. One hundred and twelve days after the operation, there was still further improvement in sensibility to
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