(Elektromagnetische Reizhebel.)
Description: This, like items 400 and 402, is designed to provide
a carefully controlled touch stimulus. Thus, this is, in essence,
also an esthesiometer, shown, mounted on a stand with a
triangular cross-section. The recording component is a bristle on
a wooden lever, on the left, fitted with a stay (Anker. A
small electromagnet (for current supply) is attached to the same
shaft on which the writing lever moves. This permits visualizing
the motion of the lever when it does have a horizontal motion.
The electromagnet can be moved closer or farther away to change
the force of the touch, and the position of the electromagnet is
indicated by a "straw" or thin pointer. Two or more of these
devices could be mounted on one stand in order to determine the
two-point threshold and Weber circles, or circular areas which
seem to be sensitive to one nerve cell. (Expanded caption
Copyright 1998, Edward J. Haupt)
(Source: Frey and Metzner. (1902). Zeitschrift für
Psychologie und Physiologie der Sinnesorgane, 29, 161-182.)
Source of illustration: Zimmermann, E. (1903). XVIII. Preis-
Liste über psychologische und physiologische Apparate
(p. 115). Leipzig: Eduard Zimmermann.
DESCRIPTORS:
Type: Component
Stimulus: Minimum touch
System: Touche
Output: Go/No-Go decision