Experimental Brain Research

, Volume 227, Issue 3, pp 343–353 | Cite as

Grapheme-color synesthetes show peculiarities in their emotional brain: cortical and subcortical evidence from VBM analysis of 3D-T1 and DTI data

  • Helena MeleroEmail author
  • Ángel Peña-Melián
  • Marcos Ríos-Lago
  • Gonzalo Pajares
  • Juan Antonio Hernández-Tamames
  • Juan Álvarez-Linera
Research Article


Grapheme-color synesthesia is a neurological phenomenon in which viewing achromatic letters/numbers leads to automatic and involuntary color experiences. In this study, voxel-based morphometry analyses were performed on T1 images and fractional anisotropy measures to examine the whole brain in associator grapheme-color synesthetes. These analyses provide new evidence of variations in emotional areas (both at the cortical and subcortical levels), findings that help understand the emotional component as a relevant aspect of the synesthetic experience. Additionally, this study replicates previous findings in the left intraparietal sulcus and, for the first time, reports the existence of anatomical differences in subcortical gray nuclei of developmental grapheme-color synesthetes, providing a link between acquired and developmental synesthesia. This empirical evidence, which goes beyond modality-specific areas, could lead to a better understanding of grapheme-color synesthesia as well as of other modalities of the phenomenon.


Grapheme-color synesthesia Voxel-based morphometry Cortical emotional areas Subcortical gray nuclei 



Grapheme-color synesthesia


Voxel-based morphometry


Diffusion tensor imaging


Diffeomorphic anatomical registration through exponentiated lie algebra method


Fractional anisotropy


Fusiform gyrus


Intraparietal sulcus


Transcranial magnetic stimulation


Oscillatory resonance supervenience model


Parahippocampal gyrus


Temporal pole


Anterior insula


Retrosplenial cortex


Anterior cingulate gyrus


Middle frontal gyrus



We thank the participants and the technical staff at the 3T scanner facility of Fundación Centro de Investigación de Enfermedades Neurológicas for their indispensable collaboration in this study. Financial support was provided by Universidad Complutense de Madrid, Fundación Centro de Investigación de Enfermedades Neurológicas and Ministerio de Ciencia e Innovación PSI2009-14415-C03-03. The authors declare that they have no competing interests. This work conforms to Standard 8 of the American Psychological Association’s Ethical Principles of Psychologist and Code of Conduct.

Supplementary material

221_2013_3514_MOESM1_ESM.pdf (317 kb)
Supplementary material 1 (PDF 317 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Helena Melero
    • 1
    • 2
    • 3
    Email author
  • Ángel Peña-Melián
    • 3
  • Marcos Ríos-Lago
    • 4
    • 5
    • 6
  • Gonzalo Pajares
    • 6
  • Juan Antonio Hernández-Tamames
    • 6
    • 7
  • Juan Álvarez-Linera
    • 6
    • 8
  1. 1.Departamento de Psicobiología, Facultad de PsicologíaUniversidad Complutense de MadridMadridSpain
  2. 2.Departamento de Investigación, Desarrollo y PromociónFundación Internacional ArtecittáGranadaSpain
  3. 3.Departamento de Anatomía y Embriología Humana I, Facultad de MedicinaUniversidad Complutense de MadridMadridSpain
  4. 4.Departamento de Psicología Básica IIUniversidad Nacional de Educación a Distancia (UNED)MadridSpain
  5. 5.Unidad de Daño CerebralHospital Beata María AnaMadridSpain
  6. 6.Laboratorio de Análisis de Imagen MédicaFundación CIEN-Fundación Reina SofíaMadridSpain
  7. 7.Departamento de Tecnología ElectrónicaUniversidad Rey Juan CarlosMadridSpain
  8. 8.Servicio de Neuroradiología, Hospital Ruber InternacionalMadridSpain

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