Synesthesia is a fascinating condition in which stimulation of one sensory modality causes experiences in a second modality. For example, when presented with musical tones, some people report seeing colors in addition to hearing those tones. Estimates of the prevalence of synesthesia range from 1 in 20 (Galton, 1880/1997) to 1 in 20,000 (Cytowic, 1989; Cytowic, 1997). We will use a combination of perceptual experiments and functional magnetic resonance imaging (fMRI) to explore the neural basis of synesthesia. We propose that number-color synesthesia is a result of neural """"""""miswiring"""""""" between areas of the fusiform gyrus involved with number-form processing (Richard, Romero, Basso, Wharton, Flitman, & Grafman, 2000; Pesenti, Thioux, Seron & De Volder, 2000) and more interior areas of the fusiform gyrus considered to be involved with processing of color (Lueck, Zeki, Friston, Deiber, Cope, Cunningham, Lammertsma, Kennard & Frackowiak, 1989; Zeki & Marini, 1998). Should this hypothesis be borne out, it would provide an existence proof of the neural miswiring hypothesis and could lead to further studies investigating other forms of synesthesia, including tone-color synesthesia and Glaton's (1880/1997) """"""""number-forms.""""""""

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
5F31MH063585-03
Application #
6608566
Study Section
Integrative, Functional and Cognitive Neuroscience 8 (IFCN)
Program Officer
Desmond, Nancy L
Project Start
2002-05-01
Project End
Budget Start
2003-05-01
Budget End
2004-04-30
Support Year
3
Fiscal Year
2003
Total Cost
$27,001
Indirect Cost
Name
University of California San Diego
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
804355790
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Hubbard, Edward M; Manohar, Sanjay; Ramachandran, Vilayanur S (2006) Contrast affects the strength of synesthetic colors. Cortex 42:184-94
Hubbard, Edward M; Arman, A Cyrus; Ramachandran, Vilayanur S et al. (2005) Individual differences among grapheme-color synesthetes: brain-behavior correlations. Neuron 45:975-85
Hubbard, Edward M; Ramachandran, V S (2005) Neurocognitive mechanisms of synesthesia. Neuron 48:509-20
Oberman, Lindsay M; Hubbard, Edward M; McCleery, Joseph P et al. (2005) EEG evidence for mirror neuron dysfunction in autism spectrum disorders. Brain Res Cogn Brain Res 24:190-8