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Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo
Published on: December 5, 2012
Coherence between motor unit discharges in response to shared neural inputs.
Madeleine M Lowery1, Lance J Myers, Zeynep Erim
1School of Electrical, Electronic and Mechanical Engineering, University College Dublin, Dublin, Ireland. madeleine.lowery@ucd.ie <madeleine.lowery@ucd.ie>
Journal of Neuroscience Methods
|May 8, 2007
Summary
Coherence analysis reveals how shared neural inputs affect motor unit firing. Higher common input frequency decreases coherence, while similar motor unit firing rates increase it.
Area of Science:
- Neuroscience
- Motor Control
- Computational Biology
Background:
- Coherence analysis quantifies correlations in motor unit discharge times.
- The relationship between coherence and shared motoneuron inputs is not fully understood.
- The link between coherence and motor unit synchronization requires clarification.
Purpose of the Study:
- To investigate how shared motoneuron inputs influence coherence in motor unit discharge patterns.
- To explore the relationship between coherence and motor unit synchronization measures.
- To utilize computer simulations for examining these neural control dynamics.
Main Methods:
- Computer simulations were used to model motor unit discharge patterns.
- Simulations varied parameters of shared motoneuron inputs.
- Coherence and synchronization indices were calculated and compared.
Main Results:
- Coherence decreased with increasing common input frequency.
- Coherence increased when common input frequency approached motor unit firing rates.
- Coherence was highest between motor units with similar firing rates.
- A linear association was found between synchronization and coherence (15-30 Hz) and common drive and coherence (0-5 Hz).
Conclusions:
- Coherence is influenced by the frequency and properties of shared motoneuron inputs.
- Interpreting coherence requires consideration of motor unit firing rates and frequency ranges.
- Findings provide insights into neural control mechanisms and signal processing in motor systems.
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