Cogent explanation based on the distinction between liking and wanting.
This suggested to many in the scientific community that these areas were the brain’s pleasure centers and that dopamine was our own internal pleasure neurotransmitter. However, this idea has since been debunked. The brain does have pleasure centers, but they are not modulated by dopamine.
So what’s going on? It turns out that, in the brain, “liking” something and “wanting” something are two separate psychological experiences. “Liking” refers to the spontaneous delight one might experience eating a chocolate chip cookie. “Wanting” is our grumbling desire when we eye the plate of cookies in the center of the table during a meeting.
Dopamine is responsible for “wanting” – not for “liking.” For example, in one study, researchers observed rats that could not produce dopamine in their brains. These rats lost the urge to eat but still had pleasurable facial reactions when food was placed in their mouths.
All drugs of abuse trigger a surge of dopamine – a rush of “wanting” – in the brain. This makes us crave more drugs. With repeated drug use, the “wanting” grows, while our “liking” of the drug appears to stagnate or even decrease, a phenomenon known as tolerance.
Source: The Conversation