Repeatidly using a substance in the same environment leads to an association, so whenever these stimuli are present, the body expects to recieve the drug.
These stimuli can cause the body to anticipate the drug, compensating in advance for the effects it usually delivers. These feelings are usually the opposite of the drug effects, so the person then wants the drug to remove these feelings.
Compensatory effects oppose the effect of the drug, so larger quanitities are needed.
If the person doesn't take the drugs, they feel withdrawal symptoms.
If an alcoholic passes a pub, they might experience a psycholoical response to the smell/sight or alcohol. This would bring back memories which would create a need to drink.
Comments
No comments have yet been made