Final answer:
Visceral pain mechanisms include distension, ischemia, and inflammation, and may present as referred pain, where pain is felt in a location different from the affected organ.
Step-by-step explanation:
The three mechanisms that produce visceral pain are distension, ischemia, and inflammation. This type of pain can be felt in unexpected locations, a phenomenon known as referred pain. For example, irritation to the diaphragm may result in pain perceived in the shoulder or neck due to shared spinal cord pathways; this explains why a cardiac event like a heart attack can cause pain in the left shoulder or arm. Sensors in the walls of digestive organs are activated by stimuli such as distension.