Figure 4

Examples of connectivity patterns emerging in plastic networks of QIF neurons. (a–c) An example of a network of six neurons, the first three of which are fast and the next three are slow. (a) One of the possible network configurations obtained in the post-transient regime with specific initial conditions. The arrows indicate the direction of the connections. All connections are realized with the maximum synaptic weight. (b) Asymptotic values of the elements of the matrix \(W_{ij}\) shown in color. This matrix corresponds to the network configuration depicted in panel (a). Panel (c) explains the structure of connections in the matrix \(W_{ij}\). Red vertical and horizontal lines separate the regions of slow and fast neurons. (d–i) Two examples of the initial and asymptotic states of a network consisting of 20 fast and 5 slow neurons. (d) Initial matrix \(W_{ij}\) with partially random and partially deterministic choice of elements (see main text for details). (e) The asymptotic values of the matrix \(W_{ij}\) obtained from the initial matrix shown in panel (d). Panel (f) shows the distribution of natural (gray bars) and actual (vertical red lines ending in crosses) periods of neurons in the post-transient regime. (g) The initial matrix \(W_{ij}\), all elements of which are chosen randomly from the interval [0, 1]. (h,i) Same as (e,f) but for the initial matrix shown in (g). The coupling strength is assumed to be \(g=0.25\). The STDP parameters are the same as in the case of two neurons.