Motor Functions and Praxis in the Elderly
José León-Carrión, Margaret J. Giannini in Behavioral Neurology in the Elderly, 2001
The basal ganglia are among the most complex structures in the brain and the study of the contribution of the basal ganglia to the planning and execution of voluntary movements is a real challenge. Studies of activation in the human brain of rCBF and rCMR have concentrated mainly on the caudate nucleus, the input striatum nucleus of the basal ganglia (putamen), and the output nucleus of the basal ganglia (globus pallidus). No information is available on the basal ganglia and the subthalamic nucleus as relates to voluntary action. But it is known that decreases in or near the substantia nigra occur during motor learning.8 Some authors consider that the increased activity in the basal ganglia during a motor task depends upon the amount of learning already involved in the performance of the task and note that the globus pallidus flow increases moderately after learning has taken place.4 The red nucleus in the mesencephalum seems to play a role in the control of movement.4
Central Modulation of Pain
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal in Principles of Physiology for the Anaesthetist, 2020
A third prominent ascending pathway that is involved in pain transmission is the spinomesencephalic tract (SMT). It originates in laminae I and IV–VI of the spinal dorsal horn, decussates and travels in the VLF to the mesencephalon (midbrain). These cells project to several nuclei in the midbrain, including the PAG, cuneiform nucleus, red nucleus, superior colliculus, pretectal nuclei, and Edinger–Westphal nucleus. The spinomesencephalic tract is somatotopically organized, with projections from caudal body regions terminating in the caudal midbrain and projections from rostral body regions terminating in more rostral regions of the midbrain. The sites of termination of this tract suggest that it may be involved in affective motor, autonomic, and anti-nociceptive responses to noxious input, such as orienting, quiescence, defence and confrontation.
Brain Motor Centers and Pathways
Nassir H. Sabah in Neuromuscular Fundamentals, 2020
The red nucleus is located in the tegmentum, or rostral midbrain, next to the substantia nigra (Figure 12.17). It is divided into two parts: the rostral parvocellular division, which in humans constitutes most of the red nucleus, and the caudal magnocellular division. The red nucleus receives input from the cerebral cortex, via the corticobulbar tract, and from the cerebellar dentate and interposed nuclei. Most of its axons project from the parvocellular division to the inferior olive, the thalamus, and reticular nuclei. The magnocellular division projects to the spinal cord as the rubrospinal tract, adjacent to the lateral corticospinal tract and the lateral reticulospinal tract (Figure 11.3).
Buyang Huanwu decoction improves neural recovery after spinal cord injury in rats through the mTOR signaling pathway and autophagy
Published in The Journal of Spinal Cord Medicine, 2023
Ying Nie, Yujie Fan, Xi Zhang, Xiaosong Li, Jian Yin, Meili Li, Zhaoyong Hu, Liang Li, Xiaoye Wang
On day 29 after the RST transection (1 d after the last motor function evaluation), 6 rats in each group were anesthetized and intracardially perfused with 4% paraformaldehyde. The brain was taken off immediately; the cerebrum and cerebellum were removed. Only the brain stem was kept and the red nucleus was located anterior to the superior colliculus. Samples were embedded in optimal cutting temperature compound, sliced at a thickness of 20 µm with a constant freezing microtome at −20°C. The sections were applied for immunofluorescence and Nissl’s staining. The rest of the rats were anesthetized and the fresh red nucleus of left side were collected for real-time qPCR detection.
Wernekink commissure syndrome secondary to a rare ‘V’-shaped pure midbrain infarction: a case report and review of the literature
Published in International Journal of Neuroscience, 2020
Mingming Dong, Lishu Wang, Weiyu Teng, Li Tian
The average age was 59 ± 13 years (range, 34–85 years) and thirteen patients (62%) were male. The most common symptom was bilateral cerebellar ataxia (100%, n = 21), all of which manifested as dysarthria, truncal and/or tetra ataxia. It is mainly owing to the interruption of the dentato–rubro–thalamic pathways prior to and after the decussation result in this clinical symptom. Wernekink commissure was thought to be the only anatomical structure in the brainstem to induce bilateral cerebellar ataxia [28]. The second common symptom was oculomotor disorders (81%, n = 17), including ophthalmoplegia (67%, n = 14) and nystagmus (62%, n = 13). INO (57%, n = 12) is the most frequent type of ophthalmoplegia due to the location of the Wernekink commissure is adjacent to MLF [6]. Besides, the third nerve paresis, vertical ophthalmoplegia and convergence impairment were also observed in some cases. Among the various nystagmus, horizontal nystagmus (43%, n = 9) was most common, while additional types can be comprised of vertical, seesaw and upbeat nystagmus [6,7]. It is significant for topical diagnosis by detecting the co-existence of bilateral ataxia and ocular signs, especially INO, highly indicating a lesion at the CPM, and a previous study even more accurately located the lesion just at the pontomesencephalic junction [33]. Palatal myoclonus and/or tremor, the consequence of destroying the fibers connected with the red nucleus or the inferior olivary nucleus, cannot be observed in every case with a total rate of 33% (n = 7). One reason was ascribed to a short period of observation and disease course [29]. Moreover, the range and location of the lesion may be a different explanation. Palatal myoclonus is usually secondary to inferior olivary degeneration (IOD) which typically caused by lesions in the dentato–rubro–olivary tract that destroyed the Guillain–Mollaret triangle circuit. Therefore, a lesion, if involved in the bilateral dentato–rubro–olivary fibers at the decussation of the superior cerebellar peduncle, may result in bilateral olivary degeneration [28]. However, IOD could not always develop to palatal myoclonus. In our study, only three patients presented with palatal myoclonus and IOD simultaneously. We have to point out that our review mainly differs from the others not only in increasing the numbers of reviewed cases, but also finding another relatively frequent symptom. Consciousness dysfunction (33%, n = 7) was as common as palatal myoclonus and/or tremor, of which hypersomnolence (24%, n = 5) was the majority. Lesions of the Wernekink commissure may involve the reticular formation at the CPM, which would affect the sleep–wake cycle. All patients of our review underwent brain MRI and revealed that all of the culprit lesions affected the region of CPM (100%, n = 21).
Related Knowledge Centers
- Ferritin
- Iron
- Midbrain
- Motor Coordination
- Hemoglobin
- Tegmentum
- Substantia Nigra
- Magnocellular Red Nucleus
- Parvocellular Red Nucleus
- Extrapyramidal System