Oh man i remember learning about this but i cant remember what the answer is i will see what I can do :D
        
             
        
        
        
I believe the answer is an eclipse.
        
             
        
        
        
Answer:
we would have to kill ourselves cause were invasive
Explanation:
 
        
             
        
        
        
Nicotine, once in the brain, will work specifically on nicotinic receptors in the brain. However, there is a common "addiction" pathway in the brain that pretty much all addictive substances go through.