Upper Motor [Neurons](/entities/neurons) (Cortical) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Upper motor neurons (UMNs) are projection neurons located in the motor [cortex](/brain-regions/cortex) that send descending projections via the corticospinal and corticobulbar tracts to lower motor neurons in the brainstem and spinal cord. [@neuroscience2001]
Upper Motor [Neurons](/entities/neurons) (Cortical) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Upper motor neurons (UMNs) are projection neurons located in the motor [cortex](/brain-regions/cortex) that send descending projections via the corticospinal and corticobulbar tracts to lower motor neurons in the brainstem and spinal cord. [@neuroscience2001]
Overview
Mermaid diagram (expand to render)
Upper Motor Neurons (Cortical), also known as Betz cells or pyramidal tract neurons, are large multipolar neurons located in the motor cortex of the brain. These neurons send their axons through the corticospinal tract to synapse with lower motor neurons in the spinal cord. Upper motor neurons are essential for voluntary movement control, muscle tone regulation, and the execution of skilled motor tasks. Degeneration of upper motor neurons is a hallmark of conditions like primary lateral sclerosis (PLS) and upper motor neuron-dominant hereditary spastic paraplegia (HSP). In neurodegenerative diseases such as ALS, both upper and lower motor neurons are affected, leading to progressive muscle weakness and paralysis. [@fundamental2012]
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Multi-Taxonomy Classification
Taxonomy Database Cross-References
Morphology & Electrophysiology
Morphology: upper motor neuron (source: Cell Ontology)
Morphology can be inferred from Cell Ontology classification
Diagnosis of ALS requires combined UMN and LMN signs
Biomarker development for UMN-specific degeneration
Background
The study of Upper Motor Neurons (Cortical) has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development. [@neuroscience2023]
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
External Links
[NeuroNames](https://neuromorphics.org/)
[Allen Brain Atlas](https://human.brain-map.org/)
[BrainFacts](https://www.brainfacts.org/)
[Lower Motor Neurons (Spinal)lower-motor-neurons-spinal)
The following diagram shows the key molecular relationships involving Upper Motor Neurons (Cortical) discovered through SciDEX knowledge graph analysis: