Seminar
Abstract:
Optimal cognitive performance depends on efficient information processing in the brain. The noradrenergic (NE) pontine nucleus Locus Coeruleus (LC), as a part of diffuse ascending arousal system, is critically involved in maintenance of vigilant state. Externally or internally driven LC activation adjusts the neuronal excitability through NE release within multiple forebrain targets of LC. The global brain state regulation, however, is not sufficient to explain the involvement of NE neurotransmission in diverse cognitive functions relying on activation of highly specific neural networks. At present, it is unknown how the evolutionary preserved and seemingly undifferentiated LC-NE neurons may modulate anatomically and functionally distinct brain networks underlying cognition. In my talk, I will briefly summarize the anatomy and the functional organization of the LC-NE system and review our recent findings. By activity monitoring of a large population of LC-NE neurons we revealed existence of different cell types in LC (1, 2); this new result supports an emergent view about heterogeineity of LC organisation. We also characterized temporal interactions of LC with cortex and hippocampus in the context of the brain state regulation, sensory processing and memory consolidation (3-6). Finally, I will demonstrate the patterns of brain-wide activity associated with phasic LC activation as revealed by fMRI, which is our ongoing work.
Publications:
1. Totah NK, Neves RM, Panzeri S, Logothetis NK, & Eschenko O (2018) The Locus Coeruleus Is a Complex and Differentiated Neuromodulatory System. Neuron 99(5):1055-1068.e1056.
2. Totah NKB, Logothetis NK, & Eschenko O (2019) Noradrenergic ensemble-based modulation of cognition over multiple timescales. Brain Research 1709:50-66.
3. Neves RM, Keulen Sv, Yang M, Logothetis NK, & Eschenko O (2018) Locus coeruleus phasic discharge is essential for stimulus-induced gamma oscillations in the prefrontal cortex. J. Neurophysiol. 119(3):904-920.
4. Novitskaya Y, Sara SJ, Logothetis NK, & Eschenko O (2016) Ripple-triggered stimulation of the locus coeruleus during post-learning sleep disrupts ripple/spindle coupling and impairs memory consolidation. Learning & Memory 23(5):238-248.
5. Marzo A, Totah NK, Neves RM, Logothetis NK, & Eschenko O (2014) Unilateral electrical stimulation of rat locus coeruleus elicits bilateral response of norepinephrine neurons and sustained activation of medial prefrontal cortex. J. Neurophysiol. 111(12):2570-2588.
6. Eschenko O, Magri C, Panzeri S, & Sara SJ (2012) Noradrenergic Neurons of the Locus Coeruleus Are Phase Locked to Cortical Up-Down States during Sleep. Cerebral Cortex 22(2):426-435.