Functional Properties of Feed-forward Inhibition
نویسندگان
چکیده
Neurons receive a large number of excitatory and inhibitory synaptic inputs whose temporal interplay determines the spiking behavior. On average, excitation and inhibition balance each other, such that spikes are elicited by fluctuations [1]. In addition, it has been shown in vivo that excitation and inhibition are correlated, with inhibition lagging excitation only by few milliseconds (∼6 ms), creating a small temporal integration window [2, 3, 4]. This correlation structure could be induced by feed-forward inhibition (FFI), which has been shown to be present at many sites in the central nervous system. To characterize the functional properties of feed-forward inhibition, we constructed a simple circuit using spiking neurons with conductance based synapses and applied spike pulse packets with defined strength and width [5]. We found that the small temporal integration window, induced by the FFI, changes the integrative properties of the neuron. Only transient stimuli could produce a response when the FFI was active, whereas without FFI the neuron responded to both steady and transient stimuli. In addition, the FFI increased the trial-by-trial precision.
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