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The term synesthesia (Greek; syn= together, aesthesia= sensation) has been used to describe a wide variety of phenomena. Most commonly, it is used to denote a condition in which stimulation in one sensory modality also gives rise to an experience in a different modality. However, conditions involving different qualities within one modality (eg, when the sight of letter shapes evokes color) are labeled synesthesia as well. Phenomena of this sort have also been reported in patients with eye disease, brain damage, and migraines (eg, Armel & Ramachandran, 1999; Jacobs, Karpik, Bozian & Gothgen, 1981; Podoll & Robinson, 2002). Similar experiences have been reported in healthy individuals using mescaline and LSD (eg, Hartman & Hollister, 1963) or drinking psychoactive brews such as Ayahuasca (Shanon, 2002). Divine intervention has also been invoked as a possible trigger of synesthesia. 1 Yet some otherwise normal, healthy individuals experience synesthesia regularly under normal conditions. 2 This is known as developmental synesthesia (for discussion, see Harrison & Baron Cohen, 1997; for synesthetes’ perspectives, see Duffy, 2001). Developmental synesthesia is the focus of this and most other