Alliesthesia

Alliesthesia (αλλoς (allós) - other, and αἴσθησις (aísthēsis) - sensation, perception ; French : alliesthésie, German : Alliästhesie) describes the dependence of the perception of pleasure or disgust perceived when consuming a stimulus on the "milieu intérieur" of the organism. Therefore, a stimulus capable of ameliorating the state of the interior milieu, will be perceived as pleasant. In contrast, a stimulus disturbing the milieu interne of the organism will be perceived as unpleasant or even painful. The sensation elicited therefore depends not only on the quality or on the intensity of the stimulus, but also on internal receptors, and is subjective.

Alliesthesia is a physiology phenomenon and should not be confounded with the pathologic symptom of allesthesia. Another phenomenon based on sensory cues and not to be confound with alliesthesia is "sensory-specific satiety".

Forms of alliesthesia

• thermic alliesthesia: alliesthesia of the thermic perception (heat and cold), which contributes fundamentally to homeostatic thermoregulation
• olfactory alliesthesia: alliesthesia of olfaction (sense of smell)
• gustatory alliesthesia: alliesthesia of taste - see primary tastes (sweet, salty, bitter, acid, umami and "calcium"[1])
• olfacto-gustatory alliesthesia or alimentary alliesthesia: alliesthesia of tastes/flavors pertaining to food intake
• visual/optic alliesthesia: alliesthesia of vision
• auditory alliesthesia: alliesthesia of the sense of hearing

Each of these forms of alliesthesia exists in two opposite tendencies:

• negative alliesthesia: transformation of the sensation from pleasure to displeasure
• positive alliesthesia: transformation of the sensation from displeasure to pleasure