Psychopharmacology

, Volume 170, Issue 3, pp 332–333

Acute tryptophan depletion does not change somatosensory evoked magnetic fields

  • Seppo Kähkönen
  • Jyrki Ahveninen
  • Iiro P. Jääskeläinen
  • Sirpa Pennanen
  • Jyrki Liesivuori
  • Vadim V. Nikulin
Short Report

DOI: 10.1007/s00213-003-1560-5

Cite this article as:
Kähkönen, S., Ahveninen, J., Jääskeläinen, I.P. et al. Psychopharmacology (2003) 170: 332. doi:10.1007/s00213-003-1560-5

Abstract

Rationale

Serotonin is shown to regulate the activity of primary auditory cortex, but little is known about serotonin modulation of other sensory cortices.

Methods

We investigated somatosensory evoked magnetic fields (SEF) to left median nerve stimulation in eight healthy subjects in a double-blind, controlled, cross-over design study after acute tryptophan depletion (ATD) and control mixture. SEFs were recorded with the whole-head magnetoencephalography 6 h after ingestion of mixtures. The SEF sources and strength were estimated by a least-squares fit of a single equivalent current dipole.

Results

ATD decreased the total and free TPR levels by 75 and 48% and control mixture increased them by 98% and 44%. ATD had no effect on the amplitudes or latencies of SEF components. The source locations of the responses were not significantly affected by ATD.

Conclusion

Serotonin does not affect stimuli processing in the primary somatosensory cortex.

Keywords

Magnetoencephalography Serotonin Somatosensory evoked magnetic fields Tryptophan 

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Seppo Kähkönen
    • 1
    • 2
  • Jyrki Ahveninen
    • 3
    • 4
  • Iiro P. Jääskeläinen
    • 2
    • 3
    • 4
    • 5
  • Sirpa Pennanen
    • 6
  • Jyrki Liesivuori
    • 7
  • Vadim V. Nikulin
    • 2
    • 8
  1. 1.Cognitive Brain Research UnitUniversity of HelsinkiHelsinkiFinland
  2. 2.BioMag LaboratoryHelsinki University Central HospitalHelsinkiFinland
  3. 3.Massachusetts General Hospital-NMR CenterHarvard Medical SchoolCharlestownUSA
  4. 4.Laboratory of Computational EngineeringHelsinki University of TechnologyEspooHelsinkiFinland
  5. 5.Apperception & Cortical Dynamics, Department of PsychologyUniversity of HelsinkiFinland
  6. 6.Occupational Hygiene and Toxicology SectionKuopio Regional Institute of Occupational HealthKuopioFinland
  7. 7.Department of Pharmacology and ToxicologyUniversity of KuopioKuopioFinland
  8. 8.Department of Clinical NeurophysiologyKarolinska HospitalStockholmSweden