China
Africa
Explore chapters and articles related to this topic
Motor Neurological Examination of the Hand and Upper Limb
Published in J. Terrence Jose Jerome, Clinical Examination of the Hand, 2022
Both these corticospinal tracts are referred to as the pyramidal tracts. Within these corticospinal tracts the fibres to the cervical upper motor neurons are located centrally and the motor neurons to the lumbar and sacral region are located peripherally.
Leg Pain
Published in Benjamin Apichai, Chinese Medicine for Lower Body Pain, 2021
The pyramidal tracts are comprised of the corticospinal tract and the corticobulbar tract. Because their nerve fibers are mainly derived from pyramidal cells in the cerebral cortex, they are called pyramidal tracts. After leaving the cerebral cortex, the pyramidal tract moves through the inner capsule and the cerebra peduncle to the medulla. Most of the nerve fibers cross over at the caudal end of the medulla to the contralateral side of the body, which is referred to as decussation of the pyramids (Rea 2015), enter the spinal cord (corticospinal) or the brain stem (corticobulbar), and control the motor function of the body.
Degenerative Diseases of the Nervous System
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
James A. Mastrianni, Elizabeth A. Harris
Clinical signs outside the spectrum of PD: Oculomotor (e.g. restricted eye movements due to supranuclear gaze palsy).Cerebellar features (nystagmus, dysarthria, wide-based gait, ataxia).Pyramidal tract signs (hyperreflexia, weakness, Babinski's sign).Nondrug-induced myoclonus.Inspiratory stridor.
Mechanisms of Modulation of Automatic Scapulothoracic Muscle Contraction Timings
Published in Journal of Motor Behavior, 2021
Samuele Contemori, Roberto Panichi, Andrea Biscarini
Our results imply the presence of at least one neural pathway that is capable to modulate the automatic timing of contraction of the scapulothoracic muscles. These muscles receive extensive projections from the extrapyramidal tracts, which are responsible for innate automatic postural/stabilization motor responses (Kandel et al., 2013). The descending cortical projections responsible for the delivering of voluntary motor commands to the spinal motoneurons and interneurons, via the pyramidal tracts, make also connections with the midbrain nuclei from which to the extrapyramidal tracts originate (Noback et al., 2005). Therefore, the midbrain nuclei of the extrapyramidal tracts might represent a candidate hub where the volitional motor commands can modulate the contraction onset time of the scapulothoracic muscles. However, we are mindful that other supraspinal or spinal circuits cannot be ruled out.
Postoperative Focal Lower Extremity Supplementary Motor Area Syndrome: Case Report and Review of the Literature
Published in The Neurodiagnostic Journal, 2021
Nicholas B. Dadario, Joanna K. Tabor, Justin Silverstein, Xiaonan R. Sun, Randy S. DAmico
Although unlikely in this case of cortical invasion in the setting of a WHO Grade II meningioma, disruption of specific FAT fibers extending to/from the SMA could have led to our patients isolated motor deficits given the importance of FAT connections in interhemispheric motor control in the motor network (Alhassani et al. 2019; Dick et al. 2019; La Corte et al. 2021). A similar hypothesis can be seen with the SCEF area, which in fact is a shared brain parcellation between both the SMA and salience networks. It is possible that these white matter fibers connecting to or from this posterior region of the SMA may facilitate quick access to the motor system, and if injured can lead to motor impairments such as in the current case. Despite these implications, the FAT’s function outside of its known roles in language processing remains poorly understood (Alhassani et al. 2019; Dick et al. 2019; La Corte et al. 2021). Furthermore, as mentioned above, the SMA region also demonstrates extensive structural connections with the pyramidal tracts and contralateral hemisphere that must be considered in the context of postsurgical motor impairments given their known implications in motor control.
Assessment of the effects of menopause on semicircular canal using the video head impulse test
Published in Journal of Obstetrics and Gynaecology, 2021
Ozlem Banu Tulmac, Gokce Simsek
During menopause, women face potential risks such as dizziness, balance problems, falls and fractures (Crilly et al. 1987; Hunter 1992; Ekblad et al. 2000; Kıran and Kaplanoğlu 2007; Terauchi et al. 2018). Falls and the resulting fractures are an important cause of morbidity and mortality, particularly in advanced age (Bergen et al. 2016). Risk factors for falls include age, female sex, balance problems and dizziness (Nevitt et al. 1991). Intact positional sense input (vision, vestibular and proprioceptive receptors/pathways), sensorimotor integration (cerebellum) and motor output (basal ganglia/corticospinal/pyramidal tract) are essential to maintain balance. Signals sent from the vestibular system ensure the stability of balance during posture changes (Dieterich and Brandt 2019). With advancing age, it may become more difficult to maintain balance due to changes of the multiple systems including vestibular system (Krager 2018).