This “is the main stress response system. It is the neuroendocrine link between perceived stress and physiological reactions to stress (Breedlove and Watson, 2013). The primary function of the activated HPA axis is to release glucocorticoids that activate short-term physiological responses to stress. While some stress is necessary for salubrious development and aging, when an individual exists in a chronic state of stress their ability to cope is compromised by dysregulation of HPA-axis and other peripheral physiological functions. The acute stress response is initiated by short-term stressors and enables short-term behavioral and physiological coping mechanisms. Whereas, the effects of long-term chronic stress may manifest not only in an overall decline in fitness or immune health, but also in neurodegenerative brain disease linked to HPA-axis dysregulation (Esch et al., 2002).
