potential source for novel equations = "A tutorial on the free-energy framework for modelling perception and learning" by *Rafal Bogacz*, http://www.sciencedirect.com/science/article/pii/S0022249615000759
potential source for novel equations = "A tutorial on the free-energy framework for modelling perception and learning" by Rafal Bogacz, http://www.sciencedirect.com/science/article/pii/S0022249615000759