The preoccupation/anticipation stage has long been hypothesised to be a key element of relapse in humans, and defines addiction as a chronic relapsing disorder. Although this stage has often been linked to the construct of craving, craving in itself has been diffi cult to measure in human clinical studies and does not always correlate with relapse.89 Nevertheless, the stage in which the individual reinstates drug-seeking behaviour after abstinence remains a focus for identifying neurobiological mechanisms of relapse and the development of medications for treatment.
