Synesthesia, a surprisingly common sensory phenomenon.
Synesthesia is the phenomena of when sensory input is crossed in the brain resulting in such sensations as smelling colors and seeing scents. “Unlike color generated from light waves or odors generated by chemical compounds, color, smell, sound, taste and touch that is experiences by synesthetes is generated by a physical stimulus that for most of us is entirely unconnected to its induced sensation,”1. Synesthetes are usually highly intelligent people who use their difference to help them learn, thus making them a very good candidate for sensory evaluation. However, this different brain wiring can be a particular problem in sensory evaluation because it is a phenomenon that will influence responses for panelists. Though it seems that synesthetes would be unable to give valid input into studies for sensory analysis; their brain paths, like that of other people, do not readily change. Thus a synesthete can be incorporated into testing by simply using their ability and working with it. Say they taste cinnamon whenever there are red lights, this would be an issue because when testing color sensitive samples the lighting will usually be red, thus the subject will always taste cinnamon in the sample, the participant could be blindfolded and test the samples that way instead.
1 Robertson, Lynn C. and Naom Sagiv. Synesthesia: perspectives from cognitive neuroscience. New York: Oxford University Press, 2005.