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.
Dopamine is quite often tagged as the 'reward' chemical, because it is released in the 'reward pathway'. It is not a coincidence that recreational drugs also bind to the same receptor sites as dopamine! But it has also been shown to be involved in arousal, motor control and even lactation.