Q: What exactly are urban legends? A: Urban legends are popular stories alleged to be true and passed from individual to individual via oral or written (e.g. forwarded email) communication.: What exactly are urban legends? A: Urban legends are popular stories alleged to be true and passed from individual to individual via oral or written (e.g. forwarded email) communication.
When a person gets injured, their brains release chemicals called opioids into the space between neurons that acts to dull the pain signals. The effect is seen the most in the brain regions called the ventral striatum, amygdala, midline thalamus, and periaqueductal gray.
1 These chemicals diffuse across the synapse (the gap) and bind with receptor molecules on the membrane of the next neuron. 2  The receptor molecules on the second neuron bind only to the specific chemicals released from the first neuron. These chemicals diffuse across the synapse (the gap) and bind with receptor molecules on the membrane of the next neuron. 2  The receptor molecules on the second neuron bind only to the specific chemicals released from the first neuron.