The \(\bf{K}\) matrix covers the topographical contributions to the MEG signal. It consists of 34 elements with positive values representing feedback connections (purple elements) and 41 elements with opposite polarity representing feedforward connections (light green elements). The feedforward connections from thalamus terminating in the three core fields also contribute to the MEG. The 13 elements on the main diagonal (cyan/teal elements) represent intra-field connections. The value of all other (white) elements is zero; they do not contribute to the MEG signal.