Friday, September 30, 2011


After listening to guest speaker David Eagleman talk about Synesthesia during a recent lecture I became extremely curious as to what it would be like to experience this condition. I did some goggling and found an interesting article which explains a little more about this condition. The article can be found here (

Synesthesia is a condition in which someone’s bodily senses are associated with completely different senses as well as that particular sense. Such as being not only able to hear sounds but also see the colors of different specific sounds and be able to tell the difference in sounds by the color they see alone. There are many different examples of how synesthesia could be perceived such as hearing colors or smelling sound or even tasting the shape or different objects. Neurologists have concluded that persons with this condition are not able to control it and automatically done. They have also been able to conclude that different synesthetic events happen at different locations outside the body. An example we discussed in class was how the different days of the week had completely separate locations outside the body and can be recalled by locating the position. Having more than one way to remember a sound or read a word vastly improves people with synesthesia ability to remember extremely large quantities of information. For example the words of this blog would all appear as different colors (with the exception of identical words). Ramachandran and Hubbard were able to determine that synesthesia is a perceived effect after the organized a test in which they sporadically placed 2's and 5's (which look similar) onto a sheet or paper or other similar area and found that people with the synesthesia effect of seeing numbers as colors were immediately able to pick out the 2's from the 5's while people without this condition had to look at each individual number to pick out the 2's. This experiment only works with association of numbers with colors however. There is an example on the webpage which helps understand what it would really be like to have this condition.

The authors were also able to determine different areas of the brain (V1-V5) which are responsible for different visual processing abilities. They found that different areas of the V series could be activated through cross activation without the stimuli of that particular V series being present. They also found that when subjects view color their specific V series number which is responsible for color may not be stimulated.

Apparently there are drugs which can cause these effects such as LSD and Mescalin which could possibly be used to further study this condition. Another interesting stat noted is that this condition is found in a ratio of 6 women to every 1 man. I am very curious as to what would happen if you showed a person with association of color to numbers a number in an opposite or complementary color they see that number as. In addition I’m curious as to what would happen if you showed the reverse of areas associated with things such as days of the week to people with this condition. If anyone has any thoughts as to what might happen please share!


  1. Hi Neuro, hope your enjoying looking up synaesthesia, really good place to see some papers and videos on synaesthesia is

    First off the 6:1 female to male ratio is now seen as an artefact of sex bias' in self-reporting synaesthesia. The only random sampling of prevalence was done by Simner et al 2006 ( ) who found that the sex differences disappeared when better methods were used.

    If you present an inducer in a different colour from their synaesthetic colour, its referred to as a synaesthetic Stroop task. Dixon et al 2004 did a really interesting task on this and found that projectors (who see the colour out there in the world) were faster at naming the synaesthetic colour, and associators (who see it in their minds eye) were faster at naming the printed colour.

  2. I cannot directly answer your questions, but I do recall from some of my neuro/cog. sci. lectures that since some people with synesthesia do cross-associate numbers, words, colors, and sounds, there has been some research into whether this makes them better mathematicians, or as is more commonly the case, artists. That's an interesting field.

    That being said, I would not imagine that complementary colors provokes the image of an 'opposite' number or anything of the like. The issue at hand is that numbers go from -infinity to infinity, and sounds from maybe 20Hz to 20kHz, but what do colors range from? Ostensibly 400nm to 700nm wavelengths, but your question relies on having 'opposites,' because our color wheel promotes the idea. I see no corollary in numbers, sounds, or words.

    my 2c