We are currently witnessing a paradigm shift in our understanding of human brain function, moving towards a clearer description of cortical processing. Sensory systems are no longer considered as 'passively recording' but rather as dynamically anticipating and adapting to the rapidly changing environment. These new ideas are encompassed in the predictive coding framework, and indeed in a unifying theory of the brain (Friston, 2010). In terms of brain computation, a predictive model is created in higher cortical areas and communicated to lower sensory areas through feedback connections. Based on my pioneering research I propose experiments that are capable of ‘brain-reading’ cortical feedback– which would contribute invaluable data to theoretical frameworks.The proposed research project will advance our understanding of ongoing brain activity, contextual processing, and cortical feedback - contributing to what is known about general cortical functions. By providing new insights as to the information content of cortical feedback, the proposal will fill one of the most important gaps in today’s knowledge about brain function. Friston’s unifying theory of the brain (Friston, 2010) and contemporary models of the predictive-coding framework (Hawkins and Blakeslee, 2004;Mumford, 1992;Rao and Ballard, 1999) assign feedback processing an essential role in cortical processing. Compared to feedforward information processing, our knowledge about feedback processing is in its infancy. The proposal introduces parametric and explorative brain reading designs to investigate this feedback processing. The chief goal of my proposal will be precision measures of cortical feedback, and a more ambitious objective is to read mental images and inner thoughts.