Translational Neuroscience

, Volume 3, Issue 1, pp 15–21 | Cite as

Synaesthesia: cross activations, high interconnectivity, and a parietal hub

  • Karsten SpechtEmail author
Research Article


This review summarizes the most recent studies on synaesthesia, particularly studies on grapheme-colour synaesthesia, time-space synaesthesia, and coloured-hearing synaesthesia. Based on behavioural as well as neuroimaging studies, there is emerging evidence that synaesthesia is not only caused by the cross activation of two sensory areas but that it may require additional binding processes, which are assumed to take place in the parietal lobe. However, divergent results exist with respect to the lateralization of this effect, i.e. whether it is the left or right parietal lobe most responsible. Studies also indicate that attention modulates the synaesthetic experience. Furthermore, it has been shown that synaesthetes demonstrate a higher level of connectivity, thus supporting the view of a genetic pre-disposition of synaesthesia.


Synaesthesia Grapheme-colour synaesthesia Time-space synaesthesia Coloured-hearing synaesthesia Cross-activation theory Two-stage model Functional imaging 


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Copyright information

© © Versita Warsaw and Springer-Verlag Wien 2012

Authors and Affiliations

  1. 1.Department of Biological and Medical PsychologyUniversity of BergenBergenNorway
  2. 2.Department of Clinical EngineeringHaukeland University HospitalBergenNorway

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