First Author | Schroeder A | Year | 2023 |
Journal | Neuron | Volume | 111 |
Issue | 5 | Pages | 727-738.e8 |
PubMed ID | 36610397 | Mgi Jnum | J:337325 |
Mgi Id | MGI:7443917 | Doi | 10.1016/j.neuron.2022.12.010 |
Citation | Schroeder A, et al. (2023) Inhibitory top-down projections from zona incerta mediate neocortical memory. Neuron 111(5):727-738.e8 |
abstractText | Top-down projections convey a family of signals encoding previous experiences and current aims to the sensory neocortex, where they converge with external bottom-up information to enable perception and memory. Whereas top-down control has been attributed to excitatory pathways, the existence, connectivity, and information content of inhibitory top-down projections remain elusive. Here, we combine synaptic two-photon calcium imaging, circuit mapping, cortex-dependent learning, and chemogenetics in mice to identify GABAergic afferents from the subthalamic zona incerta as a major source of top-down input to the neocortex. Incertocortical transmission undergoes robust plasticity during learning that improves information transfer and mediates behavioral memory. Unlike excitatory pathways, incertocortical afferents form a disinhibitory circuit that encodes learned top-down relevance in a bidirectional manner where the rapid appearance of negative responses serves as the main driver of changes in stimulus representation. Our results therefore reveal the distinctive contribution of long-range (dis)inhibitory afferents to the computational flexibility of neocortical circuits. |