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.
Communication of information between neurons is accomplished by movement of chemicals across a small gap called the synapse. Chemicals, called neurotransmitters, are released from one neuron at the presynaptic nerve terminal.holine is taken up by the neuron. When the enzyme called choline acetyltransferase is present, choline combines with acetyl coenzyme A (CoA) to produce acetylcholine. Dopamine, norepinephrine and epinephrine are a group of neurotransmitters called catecholamines.