Human Craving Research Articles

Limbic activation during cue-induced cocaine craving.

Since signals for cocaine induce limbic brain activation in animals and cocaine craving in humans, the objective of this study was to test whether limbic activation occurs during cue-induced craving in humans. Using positron emission tomography, the researchers measured relative regional cerebral blood flow (CBF) in limbic and comparison brain regions of 14 detoxified male cocaine users and six cocaine-naive comparison subjects during exposure to both non-drug-related and cocaine-related videos and during resting baseline conditions. During the cocaine video, the cocaine users experienced craving and showed a pattern of increases in limbic (amygdala and anterior cingulate) CBF and decreases in basal ganglia CBF relative to their responses to the non-drug video. This pattern did not occur in the cocaine-naive comparison subjects, and the two groups did not differ in their responses in the comparison regions (i.e., the dorsolateral prefrontal cortex, cerebellum, thalamus, and visual cortex). These findings indicate that limbic activation is one component of cue-induced cocaine craving. Limbic activation may be similarly involved in appetitive craving for other drugs and for natural rewards.

Salt, Trade, and Disease: Aspects of Development in Africa's Northern Great Lakes Region

Salt is one of the oldest raw materials known to man, perhaps the first chemical substance to be perceived as an essential resource. The antiquity of the habitual human craving for salt is partly reflected in the host of deeply-rooted beliefs concerning its necessity for physiological and psychological well-being.2 Since the Neolithic and perhaps much earlier, the irregular distribution of natural sources of salt, and hence its varying accessibility, have had consequences for human organization which transcend conventional implications of supply and demand. Indeed, although salt held the preeminent position in world trade for many centuries,3 the ordinary activities associated with its procurement and exchange often seem secondary in importance when compared with its widespread use as a standard of valuation, its influence on migration and settlement patterns, its role in shaping political and military relations, and its richly varied symbolic significance.4 Salt was a divine substance to Homer, and Plato associated it closely with the gods.5