Neural correlates of consciousness: progress and problems \cite{koch2016neural} 

Section 'Neurophysiology -activated EEG', for a crash course in classifying EEG  into wake/sleep and why this is a good but not perfect indication of consciousness.
Section 'Neural differentiation and integration', for a crash course in the role of differentation and integration in consciousness, and the PCI metric.  

Improved Measures of Integrated Information \cite{tegmark2016improved}

This is from Max! A comparison of measures of integrated information.

Nonlinear Multivariate Analysis of Neurophysical Signals \cite{pereda2005nonlinear}

In this work, we first describe the multivariate linear methods most commonly used in neurophysiology and show that they can be extended to assess the existence of nonlinear interdependences between signals. We then review the concepts of entropy and mutual information followed by a detailed description of nonlinear methods based on the concepts of phase synchronization, generalized synchronization and event synchronization. In all cases, we show how to apply these methods to study different kinds of neurophysiological data.