A major unresolved challenge for neuroscience is to understand how any physical process, such as neural activity, can give rise to a subjective phenomenon, such as a conscious experience. This question has been empirically addressed by seeking to characterize patterns of neural activity that specifically correlate with conscious experience using neuroimaging. Such conventional imaging experiments are purely observational and cannot establish a causal role for any brain areas whose activity correlates with consciousness. Approaches that disrupt brain activity either temporarily (TMS) or permanently (stroke) have been used to address causality. Here I propose using a new approach to investigate causal links between brain activity and perception. I will use real-time fMRI with neurofeedback to teach participants to voluntarily regulate either the level of brain activity or of the functional coupling of areas within early visual cortex. I will then test how self-regulating activity (or coupling) at different pre-specified levels can influence processing of a visual stimulus presented near threshold. I hypothesise that the level of activity within early visual cortex, or the coupling between areas within the visual cortex, will directly influence objective detection thresholds. By identifying neural mechanisms that lead to perception of visual stimuli, this work seeks to explore the neural basis of visual awareness with a conceptually and methodologically new approach. The proposed research marks a potentially important methodological innovation, will illuminate processes fundamental to conscious experience, and will lead to important medical applications.