The -dependent time constant and corresponding values of the -like variable under the STDP protocols used by [19].

(A) The solid black curve shows for pre-post-post spiking with and an inter-pairing frequency of , where refers to the time between the pre-synaptic spike and the second post-synaptic spike. Post-synaptic spikes were separated by . The grey curve shows under the same spiking protocol, but with an inter-pairing frequency of . The dotted black curve shows for pre-post spiking with and an inter-pairing frequency of , where refers to the time between the pre-synaptic spike and the post-synaptic spike. (B) The -like variable during the same simulations as panel A, with corresponding curves. The upper and lower horizontal lines show the LTP and LTD thresholds respectively.