Information Measures

  • Martin J. Tovée


It has long been assumed that different features of the environment are represented by different firing patterns of neurons in the brain. But it is unclear how information is encoded in the string of action potentials that stimulated neurons produce. Early studies of the activity of peripheral neurons seemed to demonstrate the existence of a neural code that represented the intensity of an external stimulus by the frequency of firing. These results have been developed into the rate coding or firing frequency theory, which implies that a neuron signals changes in the information it represents by changes in the number of impulses it produces in a period of time. The neuron integrates all the spikes reaching it over a certain sample period and produces a response over that period. Thus, each neuron functions as an “integrate-and-fire” device.1 More recently it has been suggested that the temporal pattern of the spikes, and the interval between them, may also encode information about a stimulus.2–7


Firing Rate Spike Train Information Measure Face Stimulus Coincidence Detection 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Martin J. Tovée
    • 1
  1. 1.Newcastle UniversityNewcastle upon TyneUK

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