The white song was a single note - like a distant choir lifting its voice in concerted wonder. I would wake from the dreams bewildered at the ease with which my brain, when asleep, could produce in me a tangle of sensations I could never enjoy while conscious. Although my childhood dreams had some synesthetic character, I have never had a comparable conscious experience. Although there are numerous possible combinations of synesthetic events, not every permutation is observed. That is, while many of us associate the smell of cut grass with the color green within our internal perception, a synesthete with a smell-sight perception overlap might perceive colored shapes or textures within the external environment upon smelling the grass.
Synesthesia is an additive sensory condition.
For example, there is no record of a bi-directional synesthete experiencing blue visual perceptions while drinking coffee and tasting coffee when seeing the color blue. All synesthetes have a unique and individualized set of cross-sensory perception patterns, which complicates studies of the condition. However, many theories are currently under investigation to account for the neurobiological phenomena behind synesthesia. Another potential explanation of synesthesia is the Cortical Modularity Breakdown Theory, espoused by Simon Baron-Cohen, et. These findings buttress the validity of the Neonatal Synesthesia Hypothesis in their correlation of observable behavior with the proposed neonatal organization of the brain.