Synesthesia is the neurological trait that combines two or more senses: What color is Tuesday?

How does one experience synesthesia -- the neurological trait that combines two or more senses? Synesthetes (4% of the population) may taste the number 9 or attach a color to each day of the week. Richard E. Cytowic explains the fascinating world of entangled senses and why we may all have just a touch of synesthesia. Lesson by Richard E. Cytowic, animation by TED-Ed:



Comments from Twitter on "What color is Tuesday?":

Rann Patterson @RannPatterson: yellow

PilotHealthAdvocates @ClaudiaNichols Ruby?

Jenny Sprague @xFoodAllrgyhelp: tangerine... :)

Related:

TED Talks: "Daniel Tammet has linguistic, numerical and visual synesthesia -- meaning that his perception of words, numbers and colors are woven together into a new way of perceiving and understanding the world. The author of "Born on a Blue Day," Tammet shares his art and his passion for languages in this glimpse into his beautiful mind."

Contact lenses change color when blood glucose increases in diabetics

In the future, diabetics may be able to wear contact lenses that continuously alert them to variations in their glucose levels by changing colors - potentially replacing the need to routinely draw blood throughout the day.

The non-invasive technology, developed by Chemical and Biochemical Engineering professor Jin Zhang at The University of Western Ontario, uses extremely small nanoparticles embedded into the hydrogel lenses. These engineered nanoparticles react with glucose molecules found in tears, causing a chemical reaction that changes their color.

References:
Nanocomposites could change diabetes treatment. The University of Western Ontario, 2010.

Image source: OpenClipArt.org.