FIGURE 13.4 Endocrine System Pathways in Stress Two different endocrine system pathways are involved in the response to stress (Joëls & Baram, 2009). Walter Cannon identified the endocrine pathway shown on the left side of this diagram. This is the pathway involved in the fight-or-flight response to immediate threats. Hans Selye identified the endocrine pathway shown on the right. This second endocrine pathway plays an important role in dealing with prolonged, or chronic, stressors.