The sience behind synesthesia testing.

*Disclaimer, do first the tests, before reading this*

The gold standard of testing synesthesia that is used nowadays is the called the test of consistency, or test of congruency. David Eaglmen’s synesthesia battery laid the foundation of a standardized synesthesia test, that is widely used and accepted among scientists.

It is mainly based on the fact that synesthetic perceptions, such as colors of letters, are consistent over time. People that resonate with synesthesia typically pick the same colors for their letters, numbers, weekdays and months. Unlike non-synesthetes, that choose the colors rather randomly. In order to avoid false-positive outcomes, i.e. that people that use their memory abilities during such a test are classified as synesthetes, a stroop test is applied. This works like following: an item, such as a letter or a number, is displayed for 1 second, either in the subjective right or wrong color. Synesthetes tend to score better and faster in deciding if the item was “rightly” or “wrongly” colored.

However, testing for synesthesia is challening. On the one hand, only a few types of synesthesia are tested in the commonly known synesthesia tests. For some synesthesias, such as the shapes of touch or the sound of tastes no tests are available. On the other hand, scientists are rather conservative in “diagnosing” synesthesia. So some unaware synesthetes are filtered out of studies because they do not answer questions in a typical manner. And as a last point worth to mention, some people may just never have thought about colors of letters and therefore score poorly.

In summary: synesthesia tests are a fun task to do. But do not give to much importance to it. In the end nobody can see in your mind, your perception of your sensory experiences is what matters.