Luminescence, Seeing Images, and Hearing Sounds
During qigong practice, some people sense that luminescence, written words, or strange pictures emerge in a certain part of the body, such as the forehead, hindbrain, middle of chest, lower abdomen, fingers or other body parts. They may also hear various sounds. These phenomena indicate the appearance of special functions. If these effects appear:
1) Do not panic;
2) Do not regard these phenomena as hallucinations and reject them;
3) Do not seek or be infatuated with your favorite images and sounds;
4) Do not be anxious or afraid if you see images or hear sounds that are unpleasant. Treat all these phenomena as manifestations of qigong functions.
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During qigong practice, you may hear the ringing of bells, thunder or people’s voices in your ears, belly, chest, or palms. These are the manifestations of the appearance of special functions. You may start cultivating the function of hearing subsonic sound or the ability to read written words using your ears instead of your eyes. As a matter of fact, the sounds you hear are often thoughts coming from others’ mind or subconscious. This is actually a manifestation of telepathic or mind-reading function. If these kinds of sounds appear, do not excessively pursue or resist the sounds. Do not rashly tell others about them. Try to slow your breathing down, breathing slowly and gently, almost as if you have stopped breathing. At the same time try to enhance and clarify the signals of the sounds, as well as analyze and verify their accuracy.

From SECRETS AND BENEFITS OF INTERNAL QIGONG CULTIVATION LECTURES BY QIGONG MASTER DR. YAN XIN, 1997 by The International Yan Xin Qigong Association