Julia Simner at the University of Edinburgh and her colleague, Jamie Ward, at University College London, both in the UK, showed 96 pictures of obscure items such as a gazebo, a geisha or a metronome to six subjects with lexical-gustatory synaesthesia.It's obviously different for different people, and in different contexts--as the evidence presented earlier in the article attests.
In all but one subject they managed to induce a "tip of the tongue" condition, where the person recognised the object but could not remember what it was called, what letter its name started with or how many syllables the elusive word had. The researchers found that these individuals could still identify what taste the item elicited. One woman, for instance, unable to come up with the word "gramophone", reported tasting Dutch chocolate, precisely the flavour that the word is associated with for her.
This shows that it is the meaning of the word – not the sound or spelling – that elicits the taste sensation in these people, Simner says. She suspects the associations begin in childhood.
Synaesthetes tend to experience the same taste for words with similar sounds. In one subject, for instance, not only does the word "mince" call up a mince flavour, but "prince" and "cinema" do too. This suggests that the taste is somehow tied to the sound or the spelling of the word.The fact is, the meaning of a word, the image of the word, the sound of the word, all are tied up together, sometimes literally (think of a Batman bubble that says "CRASH" or "ZORT"). Teasing apart "which is which" is probably futile--and maybe even unnecessary. Language just isn't one or the other or the other.