The new psychology / by E.W. Scripture ; with 124 illustrations.

  • Edward W. Scripture
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: The new psychology / by E.W. Scripture ; with 124 illustrations. Source: Wellcome Collection.

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    the button. Try it again. You press the button when it is blue or you forget to press it when red. If you are a nervous ]-)erson you will make several mistakes before you can get yourself to notice whether the colour is red or not before you react. After several experi- ments you settle down to a steady and reliable course of movement to red and no-movement to blue, say 38^:. The time is 13^ longer than for constant reaction to red when red is always present. The mean variation is also greater, say 6^’. It is evident that the processes occupying this interval of time are more complicated ; let us attempt to investigate these processes. Instead of red and blue, three colours, red, blue, and yellow, are used with the understanding, Reaction only to red.” The time becomes, say 40S, with a mean variation of 8^. With more colours than three there is practically no change. By thus altering the number of objects among which the stimulus occurs, we find a difference in the effect. Still another variation can be introduced. Instead of reacting to red and not to blue, 3'ou may react to red with the right hand and to blue with the left, both being on the button at the same time. The result is a trifle greater than before, say 41-, or an increase of 3^'. Again, let us use an electric key with live knobs arranged to stop the pointer of the chronoscope when any one is pressed. For red react with the thumb, and for blue with the index linger : result, say, 40-. Then for red and blue as before, and for yellow with the middle linger; result, 44-. Then as before, and for green with the ring linger ; result, 47-. Again, as before, and for black with the little linger ; result, 50-. Likewise with two live-huger keys and ten colours, the time steadily increases up to about 65s. Two processes are concerned in the reaction-times
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