A central debate in cognitive psychology and cognitive neuroscience revolves around whether attention is required for visual awareness of real-world objects. The aim of the proposed project is to help resolving this debate by determining the behavioral consequences and neural mechanisms of top-down preparation on visual awareness of natural objects. Whether we are prepared to detect objects of a specific category may strongly influence whether we consciously perceive an object. Differences in such top-down preparation may explain why different studies arrived at conflicting conclusions about the role of attention in conscious object perception. First, the effect of top-down preparation on awareness of objects will be quantified using psychophysics. Second, transcranial magnetic stimulation (TMS) guided by functional magnetic resonance imaging (fMRI) will be used to determine whether preparatory neural activity in category-specific visual cortical areas plays a causal role in top-down preparation and access to awareness. Third, the influence of top-down preparation on unconscious object representations will be measured using a novel eye tracking technique and fMRI. These studies will provide important insights into the influence and neural mechanisms of top-down influences on conscious perception and will thereby help to reconcile conflicting views on the relationship between attention and awareness.