Noise Suppression and Surplus Synchrony by Coincidence Detection
Figure 5
Neural dynamics in the regime of high input correlation and strong synchrony.
A Exemplary time course of a membrane potential driven by input containing strong, synchronous spike events. During the time period shown, five MIP events arrive (indicated by tick marks above ). The first four drive the membrane potential above the threshold
, after which
is reset to
and the neuron emits a spike (dark gray tick marks above
). The fifth event is not able to deflect
above threshold (light gray) and the membrane potential quickly repolarizes towards its steady state mean
(see text). B Time-resolved membrane potential probability density
triggered on the occurrence of a MIP event at
. Since most MIP events elicit a spike, after resetting
to
the membrane potential quickly depolarizes and settles to a steady state Gaussian distribution. The slight shade of gray observable for small
just below the threshold
is caused by the small amount of MIP events that were not able to drive the membrane potential above threshold. C Probability density of the membrane potential in steady state. Theoretical approximation (black) was computed using
and
(see text and eq:Vt), empirical measurement (gray) was performed for
(gray dashed line in B). Simulation parameters were
,
(
) and
(
) Hz. Other parameters as in Table 1.