Train in the three difficulties

Quitting cocaine does not always silence the urge.
Even after long periods of abstinence,
memories tied to the drug can suddenly reignite.

Inside a memory circuit that links emotional context to reward,
activity fell sharply.
A molecular signal accumulated inside the same neurons
and steadily altered how strongly the circuit responded to could refuse.

Because this brain region stores memories of places and experiences,
its signals to the brain's reward center
can trigger powerful urges.

As the protein accumulated, it began turning other genes on and off,
gradually changing how those cells responded held on.
The neurons became harder to activate.
Fewer signals traveled from memory circuits into the reward system.

A weaker signal from the hippocampus
may leave the reward system easier to steer by cues,
even when a person wants to stop.

The chamber is still there. The preference just hasn't been asked about in a while.