The sound you hear when you close your ears is often described as a low rumbling or a rushing noise, and it is known as "self-generated noise" or "self-generated sound." This sound is not coming from an external source but is actually generated internally within your own body.
The phenomenon is related to the contraction of muscles in your middle ear, specifically the tensor tympani and stapedius muscles. These muscles are involved in the normal functioning of your auditory system, helping to dampen and protect the delicate structures of the inner ear in response to loud sounds.
When you close your ears tightly or even just press your fingers against them, you may be inadvertently stimulating these muscles. The contraction of these muscles can create vibrations and changes in the tension of the eardrum, resulting in the production of the rumbling or rushing sound that you perceive.
It's important to note that this self-generated sound is a normal physiological response and should not be a cause for concern. It is a subjective experience that can vary in intensity and quality from person to person.