Rate coding in a chain of pulse-coupled oscillators.
The input-output relation of a chain of pulse-coupled oscillators is examined. The oscillators capture the essential aspect of the dynamics of pacemaker neurons. Inputs consist of pacemaker, and noisy trains impinging upon the first unit in the chain. The response of the chain is defined as the spike train emitted by the last unit. We observe two important phenomena in the response of the chain for a given input train, whether pacemaker or noisy. First, the mean output rate of the chain is equal to the mean input rate in the range of input rate in which one input pulse corresponds to one output spike without phase locking (1:1 alternation). Second, for the same input range, the output interspike intervals tend to the average of the input interpulse intervals in a long chain of oscillators. This behavior contrasts with the fact that the response of a single unit depends on both input rate and pattern. We show that the response of the chain is reproduced by the phase transition curve which represents the phase shift due to a single isolated pulse stimulus. This analysis reveals that the averaging of the output interspike intervals is due to the geometrical aspect of the phase transition curve. This geometrical aspect causes the dependence of the response of a single unit on input pattern.
Yamanobe
T
T
Department of Systems and Human Science, Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531, Osaka, Japan.
Pakdaman
K
K
Sato
S
S
D001683:Biological Clocks / Q000502:physiology*; D055592:Biophysical Phenomena; D001703:Biophysics; D015233:Models, Statistical; D009474:Neurons / Q000378:metabolism; D009991:Oscillometry / Q000379:methods*; D013269:Stochastic Processes; D013997:Time Factors