NeuroMap System

Development, Motor Learning and Rehabilitation

Objective: Identify patterns of dynamic motor unit activity during functional opening and closing of the hand.

The ability to investigate healthy and impaired muscle control and coordination can shed light on underlying mechanisms of motor impairments and motor retraining in neurological or neuromuscular diseases.

Such information provides an innovative alternative for further the understanding of muscle control and advancing the control of exoskeletons, assistive devices, and other robotics rehabilitation devices.

Patterns of Dynamic Motor Unit Activity

Methods

The firing activation of the extensor digitorum, flexor digitorum profundus, pronator teres, and biceps brachii muscle were investigated in conjunction with concurrent recording of finger force, joint angle, and wrist inertial measurements (Trigno™) during a drinking task in healthy individuals.

Results

Characteristic patterns of coordinated activity across different phases of the drinking task highlight the neural control mechanisms that drive the firing behavior of motor units across different muscles to produce natural movements and activities of daily living.

Other References

Lei et al. Organization of the motor-unit pool for different directions of isometric contraction of the first dorsal interosseous muscle. Muscle Nerve 2018.

McManus et al. Motor unit activity during fatiguing isometric muscle contraction in hemispheric stroke survivors. Front Human Neurosci 2017.

Miller et al. Age-related differences in twitch properties and muscle activation of the first dorsal interosseous. Clin Neurophysiol 2017.

Dai C et al. Altered Motor Unit Discharge Coherence in Paretic Muscles of Stroke Survivors. Front Neurol 2017.

Hu et al. Altered motor unit discharge patterns in paretic muscles of stroke survivors assessed using surface electromyography. J Neural Eng 2016.

McManus et al. Muscle fatigue increases beta-band coherence between the firing times of simultaneously active motor units in the first dorsal interosseous muscle. J Neurophysiol 2016.

Hu et al. Assessing altered motor unit recruitment patterns in paretic muscles of stroke survivors using surface electromyography. J Neural Eng 2015.

Hu et al. Impaired motor unit control in paretic muscle post stroke assessed using surface electromyography: a preliminary report. Conf Proc IEEE Eng Med Biol Soc 2012

Suresh et al. Examination of motor unit control properties in stroke survivors using surface EMG decomposition: a preliminary report. The 33rd Annual International Conference of the IEEE EMBS 2011

Richards & Selfe. EMG Decomposition of Vastus Medialis and Vastus Lateralis in normal subjects and patellofemoral patients: A new way of assessing the balance of muscle function? International Patellofemoral Research Retreat, 2011

De Luca & Hostage. Relationship between firing rate and recruitment threshold of motoneurons in voluntary isometric contractions. J Neurophysiol 2010