The HPNA light is only on if a device is using that connection, usually a STB connected via coax (can be over twisted pair in rare situations like apartments). It sounds like your setup uses ethernet which would not turn on the HPNA light.
The previous scene is an excerpt from Brain on Fire: My Month of Madness, and just one of many hallucinations Susannah Cahalan experienced in 2009 during her month-long hospital stay, in which she was diagnosed with a rare neurological autoimmune disease, known as anti-NMDA receptor encephalitis.
Martha has Alzheimers disease. She and her daughter Melanie provided care for Martha's mother Margaret when she had severe Alzherimer's disease. Now, Melanie, age 57, is showing signs of impaired memory. Melanie's daughter Megan is pregnant with her first child and has contacted a genetic counselor to discuss Alzheimers risk in her family.