Deep brain stimulation. Computer artwork showing an electrode sending electrical impulses to nerve cells. In the background a light micrograph (LM) of a section through grey matter in the brain, showing human nerve cells (neurones). The nerve cells consist of cell bodies (black) with large fibrous axon nerve processes leading off from them. The axons transmit nerve impulses away from the cell bodies. These nerve cells form part of the grey matter along with branched dendrite nerve fibres and small support cells (neuroglia). Dendrites conduct impulses to the cell bodies of other nerve cells.