title: Corticothalamic Synaptic Noise as a Mechanism for Selective Attention in Thalamic Neurons.
abstract: A reason why the thalamus is more than a passive gateway for sensory signals is that two-third of the synapses of thalamocortical neurons are directly or indirectly related to the activity of corticothalamic axons. While the responses of thalamocortical neurons evoked by sensory stimuli are well characterized, with ON- and OFF-center receptive field structures, the prevalence of synaptic noise resulting from neocortical feedback in intracellularly recorded thalamocortical neurons in vivo has attracted little attention. However, in vitro and modeling experiments point to its critical role for the integration of sensory signals. Here we combine our recent findings in a unified framework suggesting the hypothesis that corticothalamic synaptic activity is adapted to modulate the transfer efficiency of thalamocortical neurons during selective attention at three different levels: First, on ionic channels by interacting with intrinsic membrane properties, second at the neuron level by impacting on the input-output gain, and third even more effectively at the cell assembly level by boosting the information transfer of sensory features encoded in thalamic subnetworks. This top-down population control is achieved by tuning the correlations in subthreshold membrane potential fluctuations and is adapted to modulate the transfer of sensory features encoded by assemblies of thalamocortical relay neurons. We thus propose that cortically-controlled (de-)correlation of subthreshold noise is an efficient and swift dynamic mechanism for selective attention in the thalamus.
authors.affiliation: Unité de Neurosciences, Information et Complexité, Centre National de la Recherche Scientifique FRE-3693 Gif-sur-Yvette, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Béhuret
authors.affiliation: Unité de Neurosciences, Information et Complexité, Centre National de la Recherche Scientifique FRE-3693Gif-sur-Yvette, France; Institut National de la Santé et de la Recherche Médicale U 1127, Centre National de la Recherche Scientifique UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle ÉpinièreParis, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Deleuze
authors.affiliation: Unité de Neurosciences, Information et Complexité, Centre National de la Recherche Scientifique FRE-3693 Gif-sur-Yvette, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Bal
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001288:Attention / Q000502:physiology*; D020747:Calcium Channels, T-Type / Q000235:genetics / Q000378:metabolism; D002540:Cerebral Cortex / Q000502:physiology*; D003198:Computer Simulation; D005246:Feedback; D006168:Guinea Pigs; D007257:Information Theory; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008959:Models, Neurological; D009434:Neural Pathways / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D010465:Perception / Q000502:physiology; D017208:Rats, Wistar; D013788:Thalamus / Q000502:physiology*; D046509:Tissue Culture Techniques; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000378:metabolism
chemical_list: C498197:Cacna1g protein, mouse; D020747:Calcium Channels, T-Type; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid
keywords: activity decorrelation; corticothalamic feedback; gain control; selective attention; sensory transfer; synaptic noise; thalamic gateway; thalamocortical system