A recent experiment by conducted by the University of Sussex suggests it may be possible to learn to experience synesthesia, a rare condition that mixes up brain signals and leads people to hear colors or taste words. Researcher David Bor had volunteers read ebooks with 13 letters consistently written in a specific color. In addition, the volunteers spent 30 minutes every day associating the letters and colors, working on increasingly difficult tasks.
Synesthesia is a condition where presentation of one perceptual class consistently evokes additional experiences in different perceptual categories. Synesthesia is widely considered a congenital condition, although an alternative view is that it is underpinned by repeated exposure to combined perceptual features at key developmental stages. Here we explore the potential for repeated associative learning to shape and engender synesthetic experiences. Non-synesthetic adult participants engaged in an extensive training regime that involved adaptive memory and reading tasks, designed to reinforce 13 specific letter-color associations. Following training, subjects exhibited a range of standard behavioral and physiological markers for grapheme-color synesthesia; crucially, most also described perceiving color experiences for achromatic letters, inside and outside the lab, where such experiences are usually considered the hallmark of genuine synesthetes. Collectively our results are consistent with developmental accounts of synesthesia and illuminate a previously unsuspected potential for new learning to shape perceptual experience, even in adulthood.
People taught synaesthesia learn to read in colour