5 Supplementary Material

Here we give a general decription of the model. Complete versions of the dendritic update rules (summarised in Eqns (2) & (3)) are given below. The notation we're using admits the possible presence of biases as well as the weights (though biases typically aren't's could be added to the synaptic inputs effectively absorbing a We update the layers from bottom to top: first we update the latent or "environment" and increment Learning rules are conceptually summarised by the equations given in the main text, Eqn (6). If the prediction error and one of the presynaptic inputs are both consistently large (i.e. over a We add synaptic noise to the dendritic activations. Hz in order that noise is relatively slow and weak.