*Clinical Neurophysiology of Epileptogenic Networks DOI: http://dx.doi.org/10.5772/intechopen.104952*

complex feature-extracting properties. Many pyramidal neurons with long/extensive arborization processes geometrically integrate in time all postsynaptic EPSP and IPSP on their somatodendrites into a postsynaptic amplitude-modulated potential (analogue signal) which is translated at the axon hillock via an *all-or-none* generated response to an action potential (digital signal). This is fundamentally a nonlinear process [20–22]. Neurons essentially communicate with each other via *all-or-nothing* action potentials (a binary code of 1 or 0). The code of this digital communication lies either in the instantaneous or average firing rates (frequency modulation) or in the critical timing or phase of the firing (time/phase modulation) [23–25]. The postsynaptic potential amplitude-modulation (AM) is basically converted into an instantaneous or average firing rate of cortical pyramidal neurons, a frequency-modulation (FM) code, often seen in primary sensory/visual or motor and other neocortical or allocortical areas. The majority of cortical neurons though seem to rely on a criticaltiming and phase-modulation (PM) code for information processing. Furthermore, the firing frequency or firing rate patterns observed may reflect the level of synchrony or synchronization in the underlying spiking neurons [26–29].
