What is the condition characterized by hearing persistent or intermittent noise without an external source?

The condition characterized by hearing persistent or intermittent noise without an external source is tinnitus. Tinnitus is often described as a ringing, buzzing, hissing, or other auditory sensation that is perceived in the ears or head, even in the absence of any external sound. It can vary in intensity and can be a temporary condition or a chronic problem.

The other conditions mentioned in the choices relate to different auditory issues: hearing loss refers simply to a reduction in the ability to hear sounds. Meniere's disease is a disorder of the inner ear that can cause episodes of vertigo, tinnitus, and fluctuating hearing loss. Acoustic neuroma is a type of tumor that develops on the vestibulocochlear nerve, which can lead to hearing loss or balance issues, but it is a physical growth rather than a form of noise perception like tinnitus.

Thus, tinnitus is the specific condition associated with the experience of sound without any external auditory stimulus, making it the correct choice.