Since 3 months ago a progression of prodromal flu-like symptoms, psychiatric problems, anterograde amnesia, now involuntary movements almost seizure.

Infection: These symptoms are concerning. Can get neurological conditions affecting the brain following flu-like illness, and this is something that requires medical attention now. In situations such as they, workup often includes a brain scan and perhaps even what is called a lumbar puncture to see if there is any inflammation/infection affecting the spinal fluid.