title: Convergence of cortical and sensory driver inputs on single thalamocortical cells.
abstract: Ascending and descending information is relayed through the thalamus via strong, "driver" pathways. According to our current knowledge, different driver pathways are organized in parallel streams and do not interact at the thalamic level. Using an electron microscopic approach combined with optogenetics and in vivo physiology, we examined whether driver inputs arising from different sources can interact at single thalamocortical cells in the rodent somatosensory thalamus (nucleus posterior, POm). Both the anatomical and the physiological data demonstrated that ascending driver inputs from the brainstem and descending driver inputs from cortical layer 5 pyramidal neurons converge and interact on single thalamocortical neurons in POm. Both individual pathways displayed driver properties, but they interacted synergistically in a time-dependent manner and when co-activated, supralinearly increased the output of thalamus. As a consequence, thalamocortical neurons reported the relative timing between sensory events and ongoing cortical activity. We conclude that thalamocortical neurons can receive 2 powerful inputs of different origin, rather than only a single one as previously suggested. This allows thalamocortical neurons to integrate raw sensory information with powerful cortical signals and transfer the integrated activity back to cortical networks.
authors.affiliation: Institute of Neuroscience, Technische Universität München, D-80802 Munich, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Groh
authors.affiliation: Laboratory of Thalamus Research.
authors.forename: Hajnalka
authors.initials: H
authors.lastname: Bokor
authors.affiliation: Institute of Neuroscience, Technische Universität München, D-80802 Munich, Germany.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Mease
authors.affiliation: Laboratory of Thalamus Research.
authors.forename: Viktor M
authors.initials: VM
authors.lastname: Plattner
authors.affiliation: Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest H-1083, Hungary.
authors.forename: Balázs
authors.initials: B
authors.lastname: Hangya
authors.affiliation: Institute of Neuroscience, Technische Universität München, D-80802 Munich, Germany Focus Program Translational Neurosciences (ftn) & Institute for Microscopic Anatomy and Neurobiology, Johannes Gutenberg-University Mainz, D-55128 Mainz, Germany.
authors.forename: Albrecht
authors.initials: A
authors.lastname: Stroh
authors.affiliation: Centre de Recherche Université Laval Robert-Giffard, Laval University, Québec City, Canada G1J 2G3.
authors.forename: Martin
authors.initials: M
authors.lastname: Deschenes
authors.affiliation: Laboratory of Thalamus Research.
authors.forename: László
authors.initials: L
authors.lastname: Acsády
mesh_terms: D000818:Animals; D001710:Biotin / Q000031:analogs & derivatives; D002540:Cerebral Cortex / Q000166:cytology*; D000075402:Channelrhodopsins; D003911:Dextrans; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D007839:Functional Laterality; D008297:Male; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D008822:Mice, Transgenic; D046529:Microscopy, Electron, Transmission; D009434:Neural Pathways / Q000502:physiology*; D009474:Neurons / Q000502:physiology* / Q000648:ultrastructure; D018408:Patch-Clamp Techniques; D010835:Phytohemagglutinins; D051381:Rats; D017208:Rats, Wistar; D013569:Synapses / Q000378:metabolism* / Q000648:ultrastructure; D013788:Thalamus / Q000166:cytology*; D050599:Vesicular Glutamate Transport Protein 2 / Q000378:metabolism
chemical_list: D000075402:Channelrhodopsins; D003911:Dextrans; D010835:Phytohemagglutinins; D050599:Vesicular Glutamate Transport Protein 2; C076397:biotinylated dextran amine; C100156:leukoagglutinins, plants; D001710:Biotin
keywords: layer 5B; posterior-medial nucleus; relay; somatosensory; supralinear; top–down processing; trigeminal