| ResearchMembrane Physiology: a) The term “sodium inward rectification” was introduced for a time dependent mechanism that explains the effects of middle frequency stimulation (eg. 1.000 Hz, depending on permeability time constants). This effect enlarges selectively Na- inward currents and causes repetitive firing over long stimulation periods. b) The Hodgkin-Huxley equation system was used for quantitative analysis of combined potential and current clamp experiments on single myelinated nerve fibres of frogs. Receptor Physiology: Repetitive firing was in particular investigated in electroreceptors of dogfish proving a sensitivity of less than 0,1 µV/cm, useful for the animal in prey detection, electonavigation and communication. Nociception in humans: Development of pain models activating selectively nociceptive afferents, such as the intracutaneously applied electrical pulse (used in particular to study effects of analgesics in healthy volunteers), or the brief (1 ms) infrared laser pulse (used in clinical studies to differentiate pain disorders). This way ultralate brain potentials have been found as correlates of C-fibre mediated pain. Pain and consciousness: In cooperation withPhilips Medical Systems, Hamburg, construction, improvement and application of biomagnetometry that allows the localisation of pain processing mechanisms in the human brain with high spatial and temporal resolution. In particular, we elaborated the decisive role of secondary sensory fields in the rational assessment of pain (localisation, strength, time course) and their modifications under general anesthesia; furthermore pain inhibiting oain mechanisms and the effects of attention. |
| Further Developments Thulium-Laser-Stimulator Neurotec (Fa Carl Baasel, 82319 Starnberg) for thin fiber activation eEEG Emotion eEgg Fa Elmos Semiconductor Dortmund for permanent pain control |
Sodium inward rectification
Late and ultralate pain signals
Pain chronification