Adenosine

Caffeine is a purinergic antagonist that competitively inhibits adenosine at the sites of P1 receptors.

Caffeine acts as an antagonist at receptors in the brain for one of the chemical messengers called adenosine.

Think of adenosine as a chemical barometer that continuously registers the amount of elapsed time since you woke up this morning.

SAM: Readings confirmed. Based on the levels of adenosine in your system, the neural implant is functioning properly.

Adenosine levels can be quickly righted after a few nights of good sleep, however.