Page:Mind (New Series) Volume 6.djvu/461

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IX. NOTES AND NEWS. ON THE TEMPERATURE-SENSES. I. EXPERIMENTAL CONTRIBUTIONS TOWARDS OUR KNOWLEDGE OF THE COLD- AND WARM-SPOTS OF THE SKIN. The following is a re'sumd of the contents of an article which is being printed in extenso in Upsala Liikarefiirenings Forhandlingar 1897, and in Scandinavisches Archiv fiir Physiologic 1897. In the following resume" I have as shortly and concisely as possible brought forward the work already done by others, also reducing the critical remarks I might like to make on their work to a minimum. As to these remarks, and as. to other sides of my work, I beg to refer the reader to the above-men- tioned annuals. The observations were made at the Physiological Laboratory of this town and began in April, 1896. INTRODUCTORY. As is well known, Magnus Blix l has shown that the different kinds of sensations which are to be had from the skin can be attained only from certain distinctly localised spots, which we might call sense-spots. Thus he demonstrated that for instance sensations of warmth can be got only from certain warm-spots and sensations of cold only from certain cold-spots and that the skin between these spots is insensitive to cold and warmth. Blix stimulated the skin with pointed objects, employing elec- trical stimulation (induction-currents) as well as thermal (warm and cold metal-points). These observations have been confirmed by Donaldsort, 2 Goldscheider? Kulenburg * and others. On the other hand they have been of late severely criticised and even more or less denied by Dessoir 5 and Kiesmv. 6 liessoir considers that the temperature-spots have been obtained by artificial means : they are the result of suggestion, of unequal pressure of the skin by the cold and warm points, etc. Kiesow denies the truth of Blix' discovery in so far only as he gives out that he has hardly ever found a cold- spot which cannot be made to give a sensation of warmth from a certain temperature upwards ( + 47 - 50 C.). These two last as- sertions seem to justify the holding forth of certain measures as neces- sary when investigating these matters. These are (as already given out by Blix) : 1, the stimulus must not be too strong, else the adjoining parts of the skin will also be affected ; 2, the stimulus must be punctiform enough else the metal-point may cover a cold- and a warm-spot at the same time.