Modelling the response of scalp sensory receptors to transcranial electrical stimulation

  • V. Suihko


Transcranial electrical stimulation of the brain cause considerable discomfort to the patient. The purpose of the study was to find out whether this could be affected by the choice of stimulation parameters. A spherical volume conductor model of the head and active compartmental models of a pyramidal motor nerve and scalp nociceptor were used in combination to simulate the scalp nociception to transcranial electrical stimulation. Scalp nociceptors were excited at distances of several centimetres from the electrodes. The size of the excited scalp area correlated with the length of the stimulation pulse. The area was 12.3, 20.4 and 26.0 cm2, for a 10μs, 100μs and 1 ms constant current pulse, respectively. With a 100 μs constant current pulse, the threshold for motor excitation was 205 mA and, for nociception, it was 51 mA. There was no significant difference between constant current and capacitor discharge pulses or between electrodes of different sizes. The results imply that the use of very short stimulation pulses can reduce the pain. If a topical anaesthesia is used to reduce the pain, it has to be applied on a large area around the electrodes.


Motor cortex Motor evoked potentials Pain Electric stimulation Computer simulation 


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Copyright information

© IFMBE 2002

Authors and Affiliations

  1. 1.Department of Clinical NeurophysiologyTampere University Hospital, Tampere and Seinäjoki Central HospitalSeinäjokiFinland

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