One central oscillatory drive is compatible with experimental motor unit behaviour in XXXX .

@entity1 @entity16 @entity191 @entity400 @entity1274 @entity2472
OBJECTIVE: Pathological @entity400 are symptomatic to several @entity16 that are difficult to differentiate and the way by which central oscillatory networks entrain @entity2472 is unknown. We considered the alternative hypotheses that @entity400 arises from one oscillator (at the @entity400 frequency) or, as suggested by recent findings from the superimposition of two separate inputs (at the @entity400 frequency and twice that frequency). APPROACH: Assuming one central oscillatory network we estimated analytically the relative amplitude of the harmonics of the @entity400 frequency in the motor neuron output for different temporal behaviors of the oscillator. Next, we analyzed the bias in the relative harmonics amplitude introduced by superimposing oscillations at twice the @entity400 frequency. These findings were validated using experimental measurements of wrist angular velocity and surface electromyography (EMG) from 22 @entity1 (11 essential @entity400 , 11 @entity191 ). The ensemble motor unit action potential trains identified from the EMG represented the neural drive to the muscles. MAIN RESULTS: The analytical results showed that the relative power of the @entity400 harmonics in the analytical models of the neural drive was determined by the variability and duration of the @entity400 bursts and the presence of the second oscillator biased this power towards higher values. The experimental findings accurately matched the analytical model assuming one oscillator, indicating a negligible functional role of secondary oscillatory inputs. Furthermore, a significant difference in the relative power of harmonics in the neural drive was found across the @entity1 groups, suggesting a diagnostic value of this measure (classification accuracy: 86%). This diagnostic power decreased substantially when estimated from limb acceleration or the EMG. Signficance. The results indicate that the neural drive in pathological @entity400 is compatible with one central network providing @entity1274 at the @entity400 frequency. Moreover, the regularity of this @entity1274 varies across @entity400 pathologies, making the relative amplitude of @entity400 harmonics a potential biomarker for diagnostic use.
