Intermuscular coherence

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Intermuscular Coherence is a measure to quantify correlations between the activity of two muscles, which is often assessed using electromyography. The correlations in muscle activity are quantified in frequency domain, [1] and therefore referred to as intermuscular coherence. [2]

Contents

History

The synchronisation of motor units of a single muscle in animals and humans are known for decades. The early studies that investigated the relationship of EMG activity used time-domain cross-correlation to quantify common input. [3] [4] The explicit notion of presence of synchrony between motor units of two different muscles was reported at a later time. [5] In the 1990s, coherence analysis was introduced to examine in frequency content of common input. [2]

Physiology

Intermuscular coherence can be used to investigate the neural circuitry involved in motor control. Correlated muscle activity indicates common input to the motor unit pools of both muscles [6] [7] and reflects shared neural pathways (including cortical, subcortical and spinal) that contribute to muscle activity and movement. [8] The strength of intermuscular coherence is dependent on the relationship between muscles and is generally stronger between muscle pairs that are anatomically and functionally closely related. [9] [10] Intermuscular coherence can therefore be used to identify impairments in motor pathways. [11] [12]

See also

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References

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