Motivational Quotes

Aversion therapy has been used for many years in the treatment  of alcoholism (3). Apomorphine and emetine are the usual  drugs used as the unconditioned stimuli for nausea and vomiting, with  alcohol as the conditioned stimulus

Another recent model draws together the concepts of alliesthe-sia and interoception to account for addiction (Paulus et al., 2009). Alliesthesia refers to the notion that whether or not a stimulus is rewarding or punishing depends on the internal (bodily) state of the individual (Cabanac, 1971). Negative alliesthesia is where repeated administration of a stimulus reduces its rewarding nature, for example the hedonic effects of drugs wearing off as the brain and body homeostatically adjust over time. Positive alliesthesia is where repeated administration (or omission) of a stimulus changes the internal mieliu in such a way as to increase its rewarding effects; this is the case of the subjective effects of smoking progressively turning positive in tobacco users. Alliesthesia is believed to have an important influence on the regulation of pleasure. We experience reward based on an evaluation of the stimulus relative to current internal state, and then engage regulatory mechanisms that maxi-mize the hedonic aspects of internal state (Cabanac, 2001). Key to this regulation is the comparison of the homeostatic state emerging from the body proper and some kind of central representation of desired internal state. Again, the insula is seen as the central hub of this interoceptive comparator mechanism

As detailed above, interoception is strongly related to reward, urge, and craving, and alliesthesia emphasizes that through interoceptive processing these constructs are dependent on the pre-existing internal state of the individual, which may undergo positive/negative alliesthetic changes. Thus, three components appear critical for how an individual responds to drugs: (1) the internal or homeostatic state as signaled via afferents converging to the insular cortex; (2) the cognitive state of the individual, which includes a “contextualized” representation of the interoceptive state (Shipp, 2005); and (3) the learned associations of the external stimulus (e.g. the drug of choice) with previous outcomes including predicted internal states. These components clearly differ across individuals who are initially exposed to drugs and those who have been taking drugs for years.

In particular, negative alliesthesia refers to the notion that repeated administration of a stimulus will affect the internal milieu in such a way that the rewarding aspects of the stimulus are attenuated (e.g., the second or third piece of chocolate does not feel as good as the first). In contrast, positive alliesthesia is observed if the repeated administration (or omission) of a stimulus changes the internalmilieu in such a way as to increase its rewarding aspects. For example, fasting can enhance the subjective pleasantness of food images (Stoeckel et al., 2007). These phenomena can also be observed in animals. Specifically, pre-feeding has been associated with negative alliesthesia (Zhao and Cabanac, 1994), whereas food restriction was found to increase the sensory reward derived from alcohol, which is an example of positive alliesthesia (Soderpalm and Hansen, 1999). Based on the alliesthesia construct, some investigators proposed a dynamic, homeostatic hypothesis of pleasure regulation (Cabanac et al., 2002).

Discontinuing unhealthy behaviors, such as overeating or drug use, depends upon an individual‟s ability to overcome the influence of environmental reward cues. The strength of that influence, however, varies greatly depending upon the internal state of the body. Characterizing the relationship between interoceptive signaling and shifting drug cue valuation provides an opportunity for understanding the neural bases of how changing internal states alter reward processing more generally. Seventeen cigarette smokers rated the pleasantness of cigarette pictures when they were nicotine-sated or nicotine-abstinent. On both occasions, smokers also underwent fMRI scanning while performing a visceral interoceptive attention task and a resting-state functional connectivity scan. Hemodynamic, physiological, and behavioral parameters were compared between sated and abstinent scans. The relationships between changes in these parameters across scan sessions were also examined.