02 January 2017

Individual and species survival demand that organisms find and obtain needed resources (e.g., food and shelter) and opportunities for mating despite costs and risks. Such survival-relevant natural goals act as “rewards,” i.e., they are pursued with the anticipation that their consumption (or consummation) will produce desired outcomes (i.e., will “make things better”). Behaviors with rewarding goals tend to persist strongly to a conclusion and increase over time (i.e., they are positively reinforcing) (21). Internal motivational states, such as hunger, thirst, and sexual arousal, increase the incentive value of goal-related cues and of the goal objects themselves and also increase the pleasure of consumption (e.g., food tastes better when one is hungry) (22). External cues related to rewards (incentive stimuli), such as the sight or odor of food or the odor of an estrous female, can initiate or strengthen motivational states, increasing the likelihood that complex and often difficult behavioral sequences, such as foraging or hunting for food, will be brought to a successful conclusion, even in the face of obstacles.

We can give an opposite example. The alliesthesia is usually explained in the way we eat sweets. The first one we eat with great pleasure, every following - with less. Finally, there comes the moment when we begin to look at the sweets with disgust. Similar example can be about thirst quenching. How sweet is the first gulp of water in the hot weather and how difficult it is to drink when they make us drink much (for instance, at a gastric lavage after poisoning). Sometimes, the alcohol consumption is like an administration of a medicine. Yesterday’s drinking a lot often results in serious poisoning of the body. An addict tries to pour liquor into his or her body to avoid the withdrawal sufferings. However, its results in vomiting. Watching the lost product with sorrow such individual often continues to take another portion of alcohol. We’re going to describe the withdrawal syndrome in details further. Now we just mention that such attempts to deceive the alliesthesia are often triggered by a banal fear of the abstinence consequences.