Experimental Brain Research

, Volume 224, Issue 2, pp 233–241 | Cite as

Galvanic vestibular stimulation influences randomness of number generation

  • Elisa Raffaella FerrèEmail author
  • Eleonora Vagnoni
  • Patrick Haggard
Research Article


Successful interaction with the external environment requires a balance between novel or exploratory and routine or exploitative behaviours. This distinction is often expressed in terms of location or orientation of the body relative to surrounding space: functions in which the vestibular system plays an important role. However, the distinction can also be applied to novel versus repetitive production of any behaviour or symbol. Here, we investigated whether vestibular inputs contribute to the balance between novel and routine behaviours, independently of their effects on spatial orienting, by assessing effects of galvanic vestibular stimulation (GVS) on a random number generation task. Right-anodal/left-cathodal GVS, which preferentially activates the left cerebral hemisphere decreased the randomness of the sequence, while left-anodal/right-cathodal GVS, which preferentially activates the right hemisphere increased it. GVS did not induce any spatial biases in locations chosen from the number line. Our results suggest that vestibular stimulation of each hemisphere has a specific effect on the balance between novel and routine actions. We found no evidence for effects of non-specific arousal due to GVS on random number generation, and no evidence for effects on number generation consistent with modulation of spatial attention due to GVS.


Galvanic vestibular stimulation Randomness Exploration and exploitation Neglect 



Galvanic vestibular stimulation

R score

Redundancy score


Random number generation index


First-order differences



This work was supported by a BIAL Foundation Bursary (215/10) awarded to PH. PH was further supported by EU FP7 project VERE and by a Leverhulme Trust Major Research Fellowship.

Supplementary material

221_2012_3302_MOESM1_ESM.jpg (330 kb)
FOD distribution. First-order differences (FODs) in the L-GVS, R-GVS and PSEUDO-GVS conditions (JPEG 330 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Elisa Raffaella Ferrè
    • 1
    Email author
  • Eleonora Vagnoni
    • 2
  • Patrick Haggard
    • 1
  1. 1.Institute of Cognitive Neuroscience (ICN)University College LondonLondonUK
  2. 2.Department of Psychological SciencesBirkbeck, University of LondonLondonUK

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