the muscles. They are the brain’s way of saying, "Move that arm" or "Kick that ball". Part 1: The Ascending Pathways (The Reporters) Ascending tracts typically use a three-neuron relay system to get information to the brain. SlideServe 1st Order Neuron
These carry voluntary commands, like deciding to wave your hand. ascending and descending tracts of spinal cord ppt
These tracts act as the brain's "input" system. They typically involve a three-neuron chain: the first-order, second-order, and third-order neurons. A. Dorsal Column-Medial Lemniscal (DCML) Pathway the muscles
From receptor to the spinal cord (Dorsal Root Ganglion). 2nd Order: From the spinal cord/brainstem to the thalamus. 3rd Order: From the thalamus to the cerebral cortex. Tract Name Modality (Function) Decussation (Crossing) Dorsal Columns (Gracilis & Cuneatus) Fine touch, vibration, conscious proprioception Medulla Oblongata Lateral Spinothalamic Pain and temperature Spinal Cord (Anterior Commissure) Anterior Spinothalamic Crude touch and pressure Spinal Cord Spinocerebellar (Ant. & Post.) Unconscious proprioception for coordination Some cross twice, some remain uncrossed 2. Descending Tracts (Motor Pathways) SlideServe 1st Order Neuron These carry voluntary commands,
| Tract | Type | Crosses | Function | |-------|------|---------|----------| | Lateral Spinothalamic | Ascending | Spinal cord | Pain, temp | | Dorsal Column | Ascending | Medulla | Fine touch, vibration | | Lateral Corticospinal | Descending | Medulla | Voluntary movement | | Vestibulospinal | Descending | No | Balance, extensor tone |