This title appears in the Scientific Report :
2014
Latency of LFP beta power peak during movement preparation correlates with reaction time
Latency of LFP beta power peak during movement preparation correlates with reaction time
Beta oscillations (15-30 Hz) are a prominent feature of neuronal population signals recorded in the sensorimotor cortex during motor behavior [rev.: Kilavik et al, Exp Neurol 245:15 (2013)]. They have been extensively studied in instructed delay tasks in which a cue provides prior information about...
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Personal Name(s): | Zehl, Lyuba (Corresponding Author) |
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Denker, Michael / Grün, Sonja / Riehle, Alexa / Brochier, Thomas | |
Contributing Institute: |
Computational and Systems Neuroscience; INM-6 Computational and Systems Neuroscience; IAS-6 |
Published in: | 2014 |
Imprint: |
2014
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Conference: | Society for Neuroscience 2014, Washington DC (USA), 2014-11-15 - 2014-11-19 |
Document Type: |
Abstract |
Research Program: |
Connectivity and Activity Human Brain Project Supercomputing and Modelling for the Human Brain Signalling Pathways and Mechanisms in the Nervous System |
Publikationsportal JuSER |
Beta oscillations (15-30 Hz) are a prominent feature of neuronal population signals recorded in the sensorimotor cortex during motor behavior [rev.: Kilavik et al, Exp Neurol 245:15 (2013)]. They have been extensively studied in instructed delay tasks in which a cue provides prior information about the movement to be performed after a GO signal presented at the end of the delay. In such tasks, beta power often exhibits an initial peak of high power shortly after the cue presentation, then decreases during the delay and is lowest during movement execution. It was proposed that the pre-movement decrease in beta power is related to an increased activity in motor cortex related to the upcoming movement execution [e.g. Kilner et al, Eur J Neurosci 21:2547 (2005)]. Thus, we aim to test the hypothesis that the temporal profile of beta power modulations during movement preparation correlates with behavioral measures of the movement. To address this issue, we here analyze how reaction time (RT) as a behavioral measure relates to the modulations of motor cortical LFP beta power in monkeys trained to perform a delayed reach-to-grasp task. In this task, a cue instructs to use either a precision grip (PG) or a side grip (SG) to grasp an object. After a fixed delay of 1 s, the GO signal provides additional information about the object load and instructs the monkey to grasp the object, pull it and hold it in a narrow position window for 500 ms to receive a food reward. In the reverse task, the object load is provided first. Neuronal activity was recorded by using a 100 electrode "Utah" array, chronically implanted at the MI/PMd border. We quantify the beta power using the amplitude of the analytic signal of the beta filtered LFP and confirm that the averaged time course of beta power across trials shows the described temporal profile of power modulations. On a single trial basis, we find that the beta profiles indeed vary with RT. When the cue provides information about the grip, we observe that for short RTs (<200 ms) the initial power peak during the delay appears earlier than for long RTs (>400 ms), and find that the latency of the power peak significantly correlates with the RT. In addition, in trials with short RTs the power for PG is on average larger than for SG. In contrast, in trials with long RTs both grip types exhibit similar power profiles. Finally, in the reverse task, the profiles during the preparatory period do not correlate with the RT and are independent of the grip type. Based on these findings, we suggest that the power peak during the delay period reflects processes which are functionally related to movement planning and affected by the characteristics of the upcoming movement such as the selected grip type. |