Membrane 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 (fig. 1) over long stimulation periods b) The Hodgkin-Huxley equarion system was used for the quantitative analysis of combined potential and current clamp experiments on single myelinated nerve fibres of frogs. Receptor Physiology: Repetitive firing was furthermore 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: New pain models were developed to activate selectively nociceptive afferents in animal and man, thus as the intracutaneously applied electrical pulse (used in particular to study effects of analgesics in healthy volunteers), or the brief (0,2 ms) infrared laser pulse (used in clinical studies to differentiate pain disorders (fig. 2). Pain and Consciousness: In cooperation with Philips 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 subject's rational assessment of pain (localisation, strength, time course) and their modifications under general anesthesia, furthermore pain - inhibiting - pain mechanisms, and the effects of attention upon pain (fig, 3). | |