“…For example, the pseudo-inverse rule (also called projection rule) can increase HNNs storage capacity and improve accuracy (Wu et al, 2012;Sahoo et al, 2016), but is not local nor incremental. Moreover, recent works have explored learning rules with self-feedback connections (non-0 diagonal), and have shown higher accuracy for a high number of stored patterns (Liou and Yuan, 1999;Folli et al, 2017;Rocchi et al, 2017;Gosti et al, 2019). In summary, despite the present limitations of the ONN, features in terms of FPS, computation time and training, are encouraging toward the exploration of a wider range of applications.…”