Citcuits for VLSI Implementation of Temporally Asymmetric Hebbian Learning

Experimental data has shown that synaptic strength modification in some types of biological neurons depends upon precise spike timing differencesbetween presynaptic and postsynaptic spikes. Several temporally-asymmetricHebbian learning rules motivated by this data have been proposed. We argue that such learning rules are suitable to analog VLSI implementation. We describe an easily tunablecircuit to modify the weight of a silicon spiking neuron according to those learning rules. Test results from the fabrication of the circuit using a O.6J.lm CMOS process are given.