Touch your skin and you feel the sensation almost immediately as electrical signals shoot along nerve channels to your brain. British scientists Alan Hodgkin (inset, middle) and Andrew Huxley (bottom) discovered that these tiny waves of electricity are generated by charged atoms – sodium and potassium ions – flowing across nerve fibres when stimulated by pressure or heat. A compatriot, Sir John Eccles (top), showed that these waves travel across nerve junctions, or synapses, by triggering the release of chemicals that create channels for ions to flow between adjoining nerve cells. The three scientists shared the 1963 Nobel Prize for Medicine. Fifty years later, we are still investigating the nervous system – pictured is a false-coloured neuromuscular junction, connecting nerve and muscle cells in a fruit fly, which was studied by scientists investigating how synapses develop and are maintained.
Written by Mick Warwicker
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.