A dictionary of flavors
Lexical-gustatory synesthesia is a rare neurological condition where words evoke distinct and involuntary taste sensations. For someone with this condition, hearing, reading, or even thinking of a word like "jail" can produce the specific taste of cold, hard bacon. These experiences are simple flavors; they often include complex profiles of texture and temperature. The word "society," for instance, might taste like fried onions. This phenomenon is highly idiosyncratic, with each person having their own unique set of word-to-taste associations. It is one of the rarer forms of synesthesia, with an estimated prevalence of less than 0.2% of the population. The tastes are often linked to foods experienced during childhood, suggesting the connections form early in life as language skills develop.
The science of consistent tastes
The University of Edinburgh is a site for research into synesthesia. Studies conducted here have been central to proving that lexical-gustatory synesthesia is a genuine perceptual experience, a genuine experience, not memory or overactive imagination. The evidence lies in long-term consistency tests. Researchers document a synesthete's taste associations for a list of words and then re-test them months, or even years, later. One of the most-studied individuals, James Wannerton, has been a subject in research associated with the University of Edinburgh. His associations have remained remarkably consistent for decades. In one study, his responses were tested 27 years after his initial evaluation, showing a high degree of consistency. This level of consistency—sometimes over 99%—is far higher than that of non-synesthetes asked to invent and remember such pairings. Functional magnetic resonance imaging (fMRI) scans provide further physical evidence. When a synesthete hears or reads a trigger word, brain regions like the gustatory cortex and the insula—areas for the perception of taste—become active.