Precision of pulse-coupled networks of integrate-and-fire neurons

Some sensory tasks in the nervous system require highly precise spike train s to be generated in the presence of intrinsic neuronal noise. Collective e nhancement of precision (CEP) can occur when spike trains of many neurons a re pooled together into a more precise population discharge. We study CEP i n a network of N model neurons connected by recurrent excitation. Each neur on is driven by a periodic inhibitory spike train with independent jitter i n the spike arrival time. The network discharge is characterized by sigma ( W), the dispersion in the spike times within one cycle, and sigma (B), the jitter in the network-averaged spike time between cycles. In an uncoupled n etwork sigma (B) similar to 1/rootN and sigma (W) is independent of N. In a strongly coupled network sigma (B) similar to 1/root logN and sigma (W) is close to zero. At intermediate coupling strengths, sigma (W) is reduced,wh ile sigma (B) remains close to its uncoupled value. The population discharg e then has optimal biophysical properties compared with the uncoupled netwo rk.