Subjective everyday experience entails a well-structured and continuous flow of sensory signals, actions, thoughts and emotions. How does the brain build such a coherent representation of space and time despite the vast amount and confusing nature of the input? Our main hypothesis is that attention control mediates the flow of information in the brain, via the selection and the integration of currently relevant signals. This involves combining signals that arise in the external world with information that is already stored in the brain, such as memories, knowledge and expectations.
We use behavioral and neuroimaging methods to investigate how these bottom-up factors (e.g. salience of the external stimuli) and top-down factors (e.g. prior knowledge about familiar stimuli) affect the integration and the selection processes. We address these issues in many different ways: our experimental paradigms make use of pictures, short videos, movies and complex virtual environments. We combine computational modeling, measures of eye-movements and functional imaging to track attention control in these naturalistic situations. We use standard fMRI methods and advanced techniques to study changes of effective connectivity in the normal brain, as well as in patients with brain damage.
Our approach seeks to bridge the gap between standard laboratory experiments, which typically involve simple and stereotyped stimuli and tasks, and brain functioning in the real life. This will help us to understand how multiple cognitive systems operate together and, ultimately, how the brain generates a coherent representation of the external world.