Figure 3.

Acute (mild) stress response. In response to a mild stressor the ANS (and the whole CRN) responds with sympathetic activation, accompanied by a reciprocal lessening of vagal (parasympathetic) tone. Usually this activation will support an appropriate response to the stressor; this response will be accompanied by proprioceptive feedback that the response has been successfully completed. Sympathetic activation then diminishes, vagal tone returns to normal, and the whole CRN resets to normal resilient functioning.