Flowchart of back-propagation learning operation.

The write pulses (V_P) for the excitatory and inhibitory synapses are defined as V_PE and V_PI, respectively. V_P is slightly changed (ΔV) according to the V_P direction and the error change is calculated. When the error increases (E₂>E₁), after applying V_R at step G, V_P is switched and jumps from one curve to another in Figure 4(b). This V_P jump eliminates the hysteresis of θ₁−θ₂.