Thalamo-cortical communication and visual attention

• Applicant: Dr. Michael C. Schmid
• Subject Area: Cognitive, Systems and Behavioural Neurobiology
• Term: from 2012 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 201725190

Attention is a fundamental aspect of our visual experience: Out of the many visual events we are exposed to at almost any instant in time, only a subset is selected for conscious visual perception. It is often thought that attention is manifested in the brain as a privileged transmission of information. Although the effect of attention on neural firing rates has been observed within a number of thalamic and cortical areas, it needs to be clarified how attention benefits the relay of information across areas. Here I propose that neurons in the thalamic pulvinar nucleus facilitate the communication of visual events from one area of visual cortex to another by synchronizing the neuronal responses of both areas during attention. To address this hypothesis on a systems level, I suggest experiments in macaque monkeys performing a spatial attention task while i) neural activity from pulvinar and visual cortex is simultaneously sampled and ii) cortical responses are assessed during the precisely timed perturbation of pulvinar activity using the methods of optogenetics. A first aim of my studies is to identify the neural signatures by which information is shared between pulvinar and visual cortex during visual attention. A second aim is to understand how pulvinar activity affects the transmission of information between cortical areas. Taken together, the proposed experiments hold great promise for delineating the contribution of thalamo-cortical communication to visual attention. They will help to understand how visual awareness emerges from brain activity and how it might be affected in patient populations with brain injury.

• DFG Programme: Independent Junior Research Groups
• Major Instrumentation: Electrophysiological recording system ; Measurement of eye movement signals ; Single-unit recording optical stimulation in Pulvinar
• Instrumentation Group: 3440 Elektrophysiologische Meßsysteme (außer 300-309 und 340-343) ; 3490 Sonstige medizinische Registriergeräte und Zubehör