Hi @mmiekus, very interesting use case! This is a pity, our underlying machinery would support this effortlessly, but we are not exposing this in the Synapses interface. In fact, the on_event dictionary should only refer to pre and post, i.e. you can only set one event type for all pre and one event type for all post pathways. Fixing this in the code is almost trivial, but I’d need to have a more thorough look to make sure that this does not break anything. Do you necessarily need all these pathways to be in a single Synapses object, i.e. should they operate on the same variables? Otherwise, you could have two Synapses objects, each with a single pre/post event it listens to.