Neuronal analog-digital information transformation at the gamma frequency

The gamma-band synchronous oscillatory activity (40}60 Hz) appears in various sensory and motor cortical areas. Because both sensory stimuli and motor responses are characterized by many analog variables, questions are raised regarding whether cortical neurons manage to transmit analog information within the gamma-oscillatory activity. Here, based on the sampling theory in digital signal processing, a simpli"ed neuron model that encodes analog data into synchronous spikes in each cycle of the gamma oscillation is proposed. Stochastic noise plays an essential functional role in this encoding mechanism. 2001 Elsevier Science B.V. All rights reserved.