Insomnia is characterized by a restless mind that results in a constant firing of the neurons throughout the body, preventing the relaxation necessary to fall asleep.  Ambien works by shutting off specific neurons through a series of cellular responses.  Ambien targets the gamma-aminobutyric acid type A (GABAA) receptor complex.  This receptor is thought to be primarily located in the cerebellum, sensory motor cortex, and central nervous system (CNS).  It selectively binds to the omega one receptor on the GABAA complex.  The binding of the GABAA receptor opens chloride channels that allow an increase in chloride ions in the neuron, resulting in hyperpolarization.  This inhibits further firing of the neurons, resulting in a relaxed state and allowing sleep to occur. 
 
 

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