On The Relationship Between LFP Oscillations And Spiking Activity In Monkey Motor Cortex
-
1
CNRS - Aix Marseille Université, Institut de Neurosciences de la Timone (INT), France
-
2
Jülich Research Centre and JARA, Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6), Germany
-
3
RWTH Aachen University, Theoretical Systems Neurobiology, Germany
-
4
RIKEN, Brain Science Institute, Japan
In motor cortex, both local field potential (LFP) beta oscillations and neuronal firing rates are modulated in relation to behavior, but their direct co-modulation was barely studied. Furthermore, motor cortical spiking locks to oscillation phase [e.g. 1], but it is unclear whether neurons lock to multiple rhythms co-occurring in the LFP, and whether locking prevalence is linked to task specificities.
Multi-electrode data was recorded from monkey motor cortex during visuomotor delayed reaching [2] or grasping [3] tasks. Oscillation amplitudes and phases were calculated from the analytical signal of the LFP filtered in narrow ranges between 5-90Hz. Spiking activity was extracted for single neurons (SUA), and from the root-mean-square of the high-pass filtered signal (MUA).
Beta oscillations dominated for all monkeys. Through the behavioral trial there was a strong negative correlation between beta and MUA amplitudes, but within specific task epochs, across-trial correlations were rare. SUA subsets had different task-related firing rate profiles and were thus differently co-modulated with beta amplitude through the trial. Phase locking of spikes was significant only for dominant bands, increased with beta amplitude and was rather independent of the neuron's task-properties. The spikes of up to 40% of SUAs were locked, and their preferred phases were similar. In one monkey with two clear bands at 20 and 30 Hz, half of locked SUAs were locked to both bands in the same epochs.
In EEG literature it is often assumed that a decrease in beta amplitude reflects motor cortical activation. However, our results suggest no stereotypical relationship between beta amplitude and firing rates, beyond a general co-modulation with behavior. Beta amplitude rather reflects the level of rhythmic synchrony across neurons, independent of firing rates.
Citations
1 Denker et al. 2011, Cereb Cortex 21:2681
2 Kilavik et al. 2012, Cereb Cortex 22:2148
3 Riehle et al. 2013, Front Neural Circuits 7:48
Keywords:
Motor Cortex,
macaque,
Beta Oscillations,
firing rate,
phase locking,
visuomotor behavior
Conference:
XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014.
Presentation Type:
Poster
Topic:
Motor Behaviour
Citation:
Kilavik
B,
Brochier
T,
Grün
S and
Riehle
A
(2015). On The Relationship Between LFP Oscillations And Spiking Activity In Monkey Motor Cortex.
Conference Abstract:
XII International Conference on Cognitive Neuroscience (ICON-XII).
doi: 10.3389/conf.fnhum.2015.217.00257
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
19 Feb 2015;
Published Online:
24 Apr 2015.
*
Correspondence:
Dr. Bjørg Elisabeth Kilavik, CNRS - Aix Marseille Université, Institut de Neurosciences de la Timone (INT), Marseille, France, Bjorg.Kilavik@univ-amu.fr