Synesthesia is projected. If visual, a photism will appear outside the body in the region close to the face. Synesthetic percepts are durable and discrete. The associations for an individual Synesthete are stable over their lifetime. If a sound is blue, it will always be blue.
Synesthetic experience is memorable.
Many synesthetes exhibit hypermnesis. Synesthesia is emotional in nature. A synesthetic experience is accompanied by a sense of noetic certitude. Non Uniformity in Synesthetic Perception. In addition to these characteristics it should be added that there is no uniformity amongst the experience of synesthetes.