Fig 1: The brain as a whole can be scanned non-invasively with magnetic resonance scanning or with detectors sensitive to magnetic fields arising from electro-chemical signals. At the next organizational level, surface and depth electrodes have been used to monitor the electrical activity of a group or population of neurons. Microelectrodes can also be used to monitor the activity of a single neuron. At yet another smaller scale, patch-clamp techniques are used to measure the electrical current of a single ion channel.
Fig 2: A representative subnetwork of neurons in the hippocampus under the influence of a system of interconnected excitatory and inhibitory interneurons.
Fig 3: A hexagonal lattice of cells. Communication between cells is mediated by potassium ion diffusion between nearest neighbor cells. The dynamics at each node is governed by the same type of subnetwork as shown in the figure above.
reported by: scientists in the Sept 1999 issue of Chaos