This answers a question that was previously untested and provides a necessary component of the argument that the ancient behavior was drug-seeking rather than merely habitual.

The identification of the pain-reinforcement cycle as a mechanism for the persistence of habitual betel nut use — the dynamic by which dental damage produced by the habit creates pain that the habit temporarily relieves, driving continued use.

This is a novel contribution to understanding the mechanisms of betel nut habituation and addiction.

The documentation of the earliest known evidence for the pattern of habitual drug use separable from agricultural or food-production contexts.

The Sulawesi foragers were not using the areca nut as food — it has no nutritional value.