Dystonic neck muscles show a shift in relative autospectral power during isometric contractions

Objective<br/>To identify effects of a deviant motor drive in the autospectral power of dystonic muscles during voluntary contraction in cervical dystonia patients.<br/>Methods<br/>Submaximal (20%) isometric head-neck tasks were performed with the head fixed, measuring surface EMG of the sternocleidomastoid, splenius capitis and semispinalis...

Spectral EMG changes in Cervical Dystonia patients and the influence of botulinum toxin treatment

Botulinum toxin (BoNT) injections in the dystonic muscles is the preferred treatment for Cervical Dystonia (CD), but the proper identification of the dystonic muscles remains a challenge. Previous studies showed decreased 8–14 Hz autospectral power in the electromyography (EMG) of splenius muscles in CD patients. Cumulative distribution...

Isometric and Dynamic Control of Neck Muscles: Reflexive contributions and muscle synergies

It is well established that the central nervous system (CNS) stabilizes the head using reflexive feedback and cocontraction. The major reflexive pathways in the neck are through muscle spindles generating the cervicocollic reflex (CCR) and through the vestibular organ generating the vestibulocollic reflex (VCR). The CNS modulates the...

HEADS UP: Sensorimotor control of the head-neck system

Head-neck stabilization is inherently challenging even when stationary, requiring constant vigilance to counter the downward pull of gravity. It involves a highly complex biomechanical system comprised of a large mass (the head) balanced on top of seven vertebrae (the neck), that are in turn connected to a moving base (the torso). This multi...