(Pendelmyographion mit Helmholtzscher Kompensations-Vorrichtung)
Description: This device was used to measure how much time
elapses after a stimulus is presented before the muscle moves.
This version is equipped with two glass plates through which the
muscle-movement can be seen and which are adjustable by screws
which move the plates by means of toothed wheels. This is the
device by which Helmholtz discovered that approximately 10 ms
elapsed between the occurrence of the nerve signal and the
beginning of muscle contraction. (Expanded caption Copyright
1998, Edward J. Haupt)
(Source: None given.)
Source of illustration: Zimmermann, E. (1903). XVIII. Preis-
Liste über psychologische und physiologische Apparate
(p. 24). Leipzig: Eduard Zimmermann.
DESCRIPTORS:
Type: component
Stimulus: picture, sound
System: muscle action
Output: reaction time