Pleasure-seeking and the aetiology of drug dependence

Abstract

Experiencing pleasure is one of the fundamental abilities for which living beings have the psychological capability. Being one of the strongest motivators of human behaviour, pleasure has been used by nature as a ‘tool’ to motivate living creatures throughout the developmental chain of animal life up to the highest primate, man. Without pleasure-seeking behaviour, higher life might long since have ended. Nature has been able - generation after generation - to entice animals and man to overcome lethargy, indifference and egocentricity, even to do laborious and painful work, to tackle dangerous and risky tasks in fulfilling superindividual functions such as the continuation of the species, rearing the young, seeking improvements in doing so - with pleasure as an expected reward. We are just beginning to learn about the biological mechanisms behind such behaviour, for example, from experiments in which animals are allowed to selfstimulate certain pleasure-generating areas of the brain, neglecting food, water and sex, continuing until there is complete exhaustion and sometimes even death (Olds, 1962). We know even less about the derangement of such biological mechanisms in addiction and similar pathological conditions.