Project Details
Projekt
SPP2411 - Sensing LOOPS: cortico-subcortical interactions for adaptive sensing
Applicant
Livia de Hoz, Ph.D.
Subject Area
Cognitive, Systems and Behavioural Neurobiology
Term
since 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 520617944
Our brain perceives the world dynamically, zooming in into relevant stimuli and fading out irrelevant ones, generating skewed moment-to-moment snapshots of reality. For example, if you are in New York City in need of a cab, you will be susceptible to yellow objects, the colour of cabs in NYC. This "adaptive sensing" of the world is at the essence of the flexibility that has allowed mammals to flourish in varying environmental conditions. Adaptive sensing depends on the interaction between incoming sensory input and the feedback that can modulate it, in other words, it depends on a processing loop. Anatomists have known of feedback projections for decades. These projections often arise in the cortex and innervate numerous subcortical nuclei at various levels of the sensory processing, creating cortico-subcortical loops. Importantly, feedback projections can exceed in number their feedforward counterparts. And yet, we continue to view sensory processing as a feedforward transformation of information. Feedforward networks, however, fail to capture the high proficiency of mammalian brains to flexibly interpret a complex world on a moment-to-moment basis, according to current needs and previous experience. We must venture away from the streetlight to incorporate the role of feedback projections into our understanding of adaptive sensing. While theories on the function of feedback projections have been put forward, their investigation has been limited mostly because existing tools were not sufficiently refined to selectively target these projections. Thanks to recent technical advances, this is now possible. Indeed, we can now use genetic tools to unprecedentedly target and even manipulate both the cortical neurons that send feedback, as well as the subcortical neurons that receive it. Combined with recent advancements in high density electrophysiology and brain-wide imaging, these techniques allow us to sample and manipulate the activity of cortical and subcortical neurons even in alert behaving animals during adaptive sensing. The momentum generated by these technical developments is paralleled at the theoretical level, with the incorporation of feedback projections into current artificial network models.
DFG Programme
Priority Programmes
