Height: 16 cm
Width: 45 cm
Depth: 30 cm
Manufacturer: McGill Aerospace Medicine Research Unit
Materials: Wood, metal, wire
Date: c1980
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Dr. Richard Fraser, Director of the Maude Abbott Medical Museum, provides a brief description of the function and/or use of the equipment.
This device was used in the McGill Physiology Department student laboratory in an exercise assessing the muscle stretch reflex, run by Dr. Doug Watt. It was manufactured by Mr. Walter Kucharski of McGill’s Aerospace Medicine Research Unit around 1980.
A seated student subject first had their foot comfortably strapped into the tapper base. Electrodes were then attached to the anterior and posterior calf to apply electrical stimulation and record electrical activity (see images below).
During the experiment, a hammer delivered a tap to the Achilles (calcaneal) tendon of the strapped-in foot causing reflex contraction of the calf gastrocnemius muscle. The amplitude of the contraction was measured with an electromyograph (E), and the resulting recording displayed on an adjacent computer screen (C) and printed for further analysis (see images below).
EMG readings from a relaxed subject and from a “tapped” one who had light and strong contractions