Deepti Regmi, an 11-year-old girl from Nepal, spontaneously developed a peculiar ability last year. She is, inexplicably, able to smell colors, and can supposedly even identify them while blindfolded. Although she does not have an official diagnosis, her ability appears to be related to the sensory phenomena known as synaesthesia.
Synaesthesia causes the person’s senses to become confused, causing sensation to one sensory input (such as the eyes) to stimulate sensation in another (the nose). This is what causes Deepti to smell color, and others to visualize color when they hear music, or to taste flavors when they hear certain sounds. Any combination of this sensory “cross-wire” is possible however, and not at all limited to the examples above.