| Project Detail |
Modulation of human visual information processing by expectation and attention
Research suggests that expectation and attention modulate visual processing. For example, seeing a dog walking on the side of the road could lead to the expectation that it might run in front of your car, driving your attention to the scene and modulating how your brain processes this visual information. The underlying neural mechanisms are largely unknown. The EU-funded EXPAT project will investigate how and to what degree expectation and attention change cortical information encoding. It will also consider the potential effects on the chronology of information processing, and whether the two modulators use the same feedback mechanisms. The project will combine functional imaging and electrophysiological, computational and psychophysical approaches to address these open questions.
Our behaviours and conscious experiences are profoundly shaped by what we see. Therefore, it is not surprising that unravelling the neural mechanisms of vision ranks among the top priorities of neuroscience. This poses the challenge of unravelling how our brain creates seamless and comprehensible visual experiences from the dizzying onslaught of visual information bombarding our retinae. Previous research suggests that expectation and attention play a central role in coordinating this information extraction process. However, at present, deep insights into how these two top-down processes shape information processing in the human visual system remain elusive. EXPAT will address this outstanding knowledge gap by revealing how expectation and attention change natural image information encoding in the human brain across visual features, across brain areas and across time. To this end, EXPAT sets itself the following three objectives: 1) revealing how expectation and attention change the specificity and efficiency of information encoding in the human visual cortex, 2) measuring the impact of expectation and attention on image information encoding across cortical brain areas and between-area information transfer and 3) obtaining insights into how expectation and attention change the chronology of visual information processing. Moreover, EXPAT will address the open question of whether or not attention and expectation effects in the visual cortex are mediated by the same or by different feedback mechanisms. These objectives will be realised by using several advanced methods, including various multivariate analyses of fMRI and EEG data, a deep convolutional network-based approach for creating ‘feature-reduced’ natural images, a multivariate brain connectivity measure and a psychophysical technique for measuring the informativeness of image features. |
