Our accelerating multimedia-dominated word requires us to cope with an ever-growing flood of visual impressions in an efficient way. This particularly includes parallel-processing of visual information. Parallel processing, however, is limited by the speed and flexibility of attentional resource allocation, which unfortunately decrements with age. This project aims to understand which processes and structural properties of the human cortex underlie efficient parallel processing by employing high-resolution spatiotemporal brain imaging (EEG,MEG, fMRI) and structural imaging methods. We particularly focus on the relationship between the speed of cortical processing and the degree of cortical myelination as a function of age. To assess parallel processing experimentally, we use multiple object tracking (MOT) where participants are to track multiple independently moving objects, as well as multiple feature tracking (MFT) requiring participants to track multiple feature-values of the same object.
Prof. Dr. med. Jens-Max Hopf
Jens- Max Hopf is the head of the Cognitive Neurophysiology Group and chair for Cognitive Neurophysiology at the medical faculty of the Otto-von-Guericke University Magdeburg. He is also head of the guest-research group visual attention at the Leibniz Institute for Neurobiology in Magdeburg. His research focuses on mechanism underlying attentional selection in human visual cortex using non-invasive neuroimaging methods, including electromagnetic brain recordings (MEG/EEG) and functional MRI.
Prof. Dr. med. Mircea Ariel Schoenfeld
Ariel Schoenfeld is the head of the experimental neurology group and chair for experimental neurology and functional neuroimaging at the medical faculty of the Otto-von-Guericke University Magdeburg. He is also medical director of the Kliniken Schmieder hospital in Heidelberg. He focusses on the neural mechanisms of perception and attention in the visual domain in health and disease with a special emphasis on these processes in patients with lesions within the CNS. The research addresses basic science as well as clinical-pathological aspects using multimodal structural and functional neuroimaging (structural and functional MRI, EEG and MEG) methods.
Dr. Mandy Bartsch
I am working as a postdoc in the research group of Prof. Jens-Max Hopf at the LIN and I am particularly interested in human attention and perception as well as science communication. To track the spatiotemporal dynamics of the cortical processes underlying attention allocation, I measure EEG and MEG in healthy participants, while they perform tasks on the screen.
Dr. Hendrik Griep
Dr. Christian Merkel
Speed of attentional allocation as a limit of parallel processing
According to our central working hypothesis, subjects cannot attend multiple feature-values of an object (like different colors) at a time. Instead, they are focused one at a time in fast cycles. This cycling of attention through the feature values gives an impression of simultaneous processing. In essence, however, parallel processing would be a serial cycling process, whose limits are set by the speed of the cycle. There is a clear link between neural myelination and the speed and accuracy of neural transmission, hence our goal to clarify the relation between cortical myelination and the efficiency of parallel processing.
We conceive of visual attention as the ability to scrutinize and select details of a visual scene with preference. This has the beneficial effect of better and faster detection, processing, and release of action. It is also possible to scrutinize and select items away from gaze (outside foveal vision), which is referred to a covert visual attention. Attention can be allocated to objects, locations, and features, which is called objects-based, space-based, and feature-based attention, respectively.
Visual attention plays a huge role in more natural environments of daily life. Hereby, scenes are more dynamic and complex compared to the ‚laboratory’. However, we are still able to navigate in such an environment by being able to attend multiple dynamic pieces of visual information simultaneously. Research shows that up to 4 or 5 visual objects can be captured by attention and that subjects are able to track that information not just through their location within the visual field but many other visual properties.
Object Tracking as a cognitive resource
The ability to track multiple objects over time within our visual environment is an indicator of cognitive health. High functioning cognitive individuals show high scores in object tracking tasks. Research shows that exercising object tracking can increase general visual cognitive performance and maintain cognitive flexibility.
Goals of our Project
This project seeks to clarify the mechanisms and limitations that underlie the flexible cognitive resource allocation in situations where multiple visual input streams need to be simultaneously processed like when navigating highly dynamic visual scenes. We aim at pinpointing the cortical structures and understand the role and speed of cyclic resource allocation of attention as a limit of parallel processing. In addition, we seek to characterize the relation between cortical myelination and the efficiency of parallel processing in MOT and FMT. of These processes will be investigated as a function of age. The potential of the skill of tracking multiple objects/features to retain cognitive flexibility in old age is being examined.
Publications of the Project B05
Christian Merkel, Jens-Max Hopf, Mircea Ariel Schoenfeld Eur J Neurosci (2022)