English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Poster

Monitoring large populations of locus coeruleus single units reveals the heterogeneous and non global nature of the norepinephrine neuromodulatory system

MPS-Authors
/persons/resource/persons192680

Totah,  NK
Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society;
Max Planck Institute for Biological Cybernetics, Max Planck Society;

/persons/resource/persons84105

Neves,  RM
Max Planck Institute for Biological Cybernetics, Max Planck Society;
Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society;

/persons/resource/persons84966

Panzeri,  S
Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society;
Max Planck Institute for Biological Cybernetics, Max Planck Society;

/persons/resource/persons84063

Logothetis,  NK
Max Planck Institute for Biological Cybernetics, Max Planck Society;
Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society;

/persons/resource/persons83895

Eschenko,  O
Max Planck Institute for Biological Cybernetics, Max Planck Society;
Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society;

Locator

Link
(Any fulltext)

Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Totah, N., Neves, R., Panzeri, S., Logothetis, N., & Eschenko, O. (2016). Monitoring large populations of locus coeruleus single units reveals the heterogeneous and non global nature of the norepinephrine neuromodulatory system. Poster presented at 46th Annual Meeting of the Society for Neuroscience (Neuroscience 2016), San Diego, CA, USA.


Cite as: http://hdl.handle.net/21.11116/0000-0000-7AF0-8
Abstract
Cognitive theories assume that the locus coeruleus (LC), a brain stem neuromodulatory nucleus, broadcasts a redundant signal to the entire forebrain due to synchronized activity of a homogeneous population of diffusely projecting norepinephrine (NE) neurons. Until recently, technical challenges limited recordings to 1-2 LC single units, which was insufficient for characterizing the diversity of LC cell types and their ensemble activity patterns. We recorded as many as 75 single units simultaneously in the urethane-anesthetized rat using a high-density multi-electrode array and analyzed 11893 unit pairs. To assess input-output specificity of LC units, we electrically stimulated 15 forebrain LC projection sites and analyzed evoked orthodromic and antidromic LC spiking. Using noise and cross correlation analyses, we assessed the heterogeneity of unit activity with respect to input-output circuits. Our results revealed 2 cell populations differing by spike width (Type 1: 461±14μs, Type 2: 1076±9μs) and rate (Type 1: 1.6±0.06Hz, Type 2: 0.84±0.04Hz). NE identity was confirmed for both types by a α2 agonist. Spontaneous noise correlations were weak and did not depend on linear distance, but Type 1 units exhibited higher correlations with one another (pair of Type 1’s: 0.138±0.007, Type 2’s: 0.049±0.001, mixed Type1/2 pair: 0.038±0.002 in 200ms bins). Evoked noise correlations were also weak (Type 1: 0.155±0.009, Type 2: 0.051±0.006, Type 1/2: 0.040±0.008, in 750ms window after five 5mA, 0.5ms, 30Hz foot shocks). Consistent with weak noise correlations, the majority (77) of pairs did not have any significant spike count change at any cross-correlelogram bin (-2 to +2s). Some pairs were correlated (from 0 to +50ms or +1.0 to 1.5ms) or anticorrelated (+1.0 to 2.0ms). We defined projection targets for 65 of 205 units. 53 of those projected to only 1 forebrain site and the remainder projected to multiple (up to 8) sites. Both cell types projected widely to the forebrain. Unit pairs projecting to thalamus had significantly higher noise correlations (0.198±0.015) than pairs with diverging projections (0.132±0.011). PFC input to the LC was area-specific: PL stimulation decreased and IL increased spiking (PL: 9 of units dec., 3 inc.; IL: 1 dec., 14 inc.). PFC stimulation also decorrelated LC activity (200ms before / after stimulation in PL: 0.063±0.005 / 0.050±0.005 and IL: 0.053±0.006 / 0.038±0.007). Thus, we found 2 LC cell types differing in spike width, rate, and noise correlation; however, overall correlations were weak. These findings challenge the prevailing view that LC cells are physiologically similar and are homogenously driven to provide a global signal.