EMG study of the anterior, superior and posterior auricular muscles in man.

Anterior, superior and posterior auricular muscles were studied electromyographically by means of wire electrodes. During ear movement the three muscles acted as a group and the movement was always directed upwards and backwards. The highest electrical activities were observed during natural smiling and yawning. Mouth opening without the drawing backwards of the comissura labiorum and the displacement of galea aponeurotica also produced electrical activity by the auricular muscles, with however, less intensity and in only 50% of the cases studied.