Introduction Footnotes1. The nervous system (including the brain) consists of cells, neurons, that have an elongated part (axon) and connect to other neurons through structures called synapses. Under certain conditions a neuron becomes "excited" transmitting an electric wave called action potential. When displayed on an oscilloscope the wave has the form of a spike that has a fixed size for a given preparation. The fact that a neuron can have only one of two states (quite or transmitting a spike of fixed size) led some people to think about parallels between computers and brains. It turns out that while the spike of the action potential has a fixed amplitude, a neuron may fire several of them so that time between spikes seems to be an important carrier of information and that is certainly not binary. Back to the Introduction |