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.
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Acknowledgements
This work was supported by the Helsinki University Central Hospital Research Funds and the Academy of Finland. We thank Anna Nikulina for help in SEF analysis.
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Kähkönen, S., Ahveninen, J., Jääskeläinen, I.P. et al. Acute tryptophan depletion does not change somatosensory evoked magnetic fields. Psychopharmacology 170, 332–333 (2003). https://doi.org/10.1007/s00213-003-1560-5
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DOI: https://doi.org/10.1007/s00213-003-1560-5