Current Psychiatry Reports

, Volume 9, Issue 3, pp 193–199 | Cite as

Neurophysiology of synesthesia

  • Edward M. HubbardEmail author


Synesthesia is an experience in which stimulation in one sensory or cognitive stream leads to associated experiences in a second, unstimulated stream. Although synesthesia is often referred to as a “neurological condition,” it is not listed in the DSM IV or the ICD classifications, as it generally does not interfere with normal daily functioning. However, its high prevalence rate (one in 23) means that synesthesia may be reported by patients who present with other psychiatric symptoms. In this review, I focus on recent research examining the neural basis of the two most intensively studied forms of synesthesia, grapheme → color synesthesia and tone → color synesthesia. These data suggest that these forms of synesthesia are elicited through anomalous activation of color-selective areas, perhaps in concert with hyper-binding mediated by the parietal cortex. I then turn to questions for future research and the implications of these models for other forms of synesthesia.


Transcranial Magnetic Stimulation Auditory Word Early Visual Area Visual Word Form Area Color Synesthete 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Current Medicine Group LLC 2007

Authors and Affiliations

  1. 1.INSERM Unité 562-Neuroimagerie CognitiveCEA/SAC/DSV/DRM/NEUROSPINGif-Sur-YvetteFrance

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