An audiovisual teaching model of the muscle spindle

Students in biology and medicine often have difficulty in visualizing the structure, function and disease of complex integrated body systems. One example in neurophysiology is the muscle spindle and Golgi tendon organ. A model is described which demonstrates the properties of these two muscle receptors. The model combines mechanical elements, which can change their length to represent muscle contraction, with an electronic representation of the passage of action potentials along 'nerves', indicated by light-emitting diodes and loudspeakers. The model has been in use for some years as a supplement to conventional teaching methods. In a recent questionnaire about the model, a group of medical students responded favourably. We suggest that models such as this are valuable teaching aids.