Transkranielle Magnetstimulation zur neurobiologischen Charakterisierung somatoformer Störungen

Zusammenfassung

Somatoforme Störungen sind Krankheitsbilder, bei denen die Patienten über körperliche Beschwerden klagen, ohne dass sich hierfür ein spezifischer pathophysiologischer Prozess finden lässt. Die Ätiopathogenese dieser Erkrankungen ist weitestgehend unbekannt. Neben psychischen Faktoren wird eine Beteiligung neurobiologischer Prozesse diskutiert. Mithilfe der transkraniellen Magnetstimulation (TMS) ist es möglich, neurobiologische Prozesse durch die Erfassung kortikaler Erregbarkeitsparameter in vivo zu detektieren. Auf dieser Technik basierend, wurde das kortikale Exzitabilitätsprofil bei Patienten mit subjektiv empfundener Elektrosensibilität erfasst. Es fand sich im Vergleich zu gesunden alters-und geschlechtsparallelisierten Kontrollen eine Verlängerung der „Cortikalen Silent Period” (CSP) als Ausdruck einer verstärkten inhibitorischen Transmission in kortikal-subkortikalen Schleifensystemen. In Einklang mit neuropsychologischen Daten verweisen diese Ergebnisse auf eine mögliche Störung in der sensorischen Informationsverarbeitung.

Summary

Somatoform disorders are characterised by patients suffering from multiple somatic complaints without an underlying pathophysiological process sufficiently explaining these symptoms. The etiology of these disorders is largely unknown. Besides psychological factors neurobiological processes might be involved. Using transcranial magnetic stimulation (TMS), neurobiological processes can be detected in vivo by measuring parameters of cortical excitability. Based on these technique, parameters of cortical excitability were measured in subjectively electrosensible patients. Compared to healthy age-and gender-matched controls, the “cortical silent period” (CSP) was prolonged in these patients indicating an enhanced inhibitory neurotransmission in cortical-subcortical loops. In line with neuropsychological data these results point to potential disturbances in the cortical processing of sensory information.

Schlüsselwörter

Subjektive Elektrosensibilität - Cortikale Silent Period - somatoforme Störungen - transkranielle Magnetstimulation

Keywords

Subjective electrosensibility - cortical silent period - somatoform disorders - transcranial magnetic stimulation

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