Neuroborreliosis is a neurological manifestation of Lyme disease caused by infection with Borrelia bacteria transmitted through tick bites. It occurs when the bacteria spread to the central or peripheral nervous system, leading to inflammation of nerve tissues. Symptoms may include severe headaches, neck stiffness, facial nerve paralysis (often presenting as drooping on one side of the face), numbness or tingling in the limbs, cognitive difficulties, and in some cases, meningitis-like features. Neuroborreliosis can develop weeks to months after the initial infection and may vary in severity. Diagnosis typically involves clinical evaluation, blood tests, and analysis of cerebrospinal fluid to detect evidence of infection and immune response within the nervous system.