neuron. Action potentials of other upstream neurons, which fire outside this critical time window (i.e., non-synchronously), can only be part of another assembly. The reader-integrator mechanism can therefore objectively determine whether neurons are part of the same assembly and serve the same goal (i.e., the discharge of the reader neuron) or belong to different assemblies (Figure 1C). The length of τ is affected by a number of factors, including the background activity in the network and availability of subcortical neuromodulators (cf., Destexhe et al., 2003). In the intact waking cerebral cortex, τ of principal cells is approximately 10–30 msec (Koch et al., 1996).
