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.
In these cases, any elevation of the pressure in the pulmonary circulatory system (due to pulmonary hypertension, temporarily while coughing, etc.) can cause the foramen ovale to remain open. This is known as a patent foramen ovale (PFO), which is not necessarily a type of atrial septal defect.