Preadaptation and the puzzles and properties of pleasure.

Sensory pleasures derive primarily from the contact senses that cover the body surface and the body apertures. It is proposed that, by the processes of preadaptation and increased accessibility, the subjective and expressive aspect of this pleasure system is, in later evolution and development, extended to a wider range of pleasure elicitors, including aesthetic and mastery pleasures. Many basic principles of hedonic systems may be studied in the more primitive sensory pleasure system. These include the properties of context dependence and the mappings between remembered, experienced, and anticipated pleasures. Pleasure in the food domain is specifically considered, including the elicitors of pleasure, the role of context, and the acquisition of likes and dislikes (hedonic changes). Special attention is paid to hedonic reversals, in which innately negative sensory hedonic responses become positive (for example, the case of chili pepper). It is argued that on the input/appraisal side, basic sensory pleasures are qualitatively different from aesthetic pleasures (such as music), but that both feed into the same subjective/expressive system. Some basic features of sensory pleasures are listed.