The initial slide indicates how a healthy ANS should work. Everyone has stressful events that cause the SNS (usually referred as the  Flight, Fright or Freeze (FFF) response) to become aroused, but after that event has past, the PNS should kick back in and bring us back to a harmonious state. But if that stressful event continues over time or more events continue to occur, the ANS gets out of sync, which may result in long term emotional, mental or physiological problems. If the body stays in an aroused unhealthy state, for a sustained period of time, a new baseline is set. The longer this cycle continues, the harder it is for ANS to go back to normal. This is where Biofeedback or Neurofeedback can help.