– Detail Fasciculus Gracilis vs. Cuneatus with text bullet points on one side and a trajectory diagram on the other.
| Feature | DCML | Spinothalamic | | :--- | :--- | :--- | | | Fine touch, vibration, proprioception | Pain, temperature, crude touch | | Peripheral Fiber | Large, myelinated (A-alpha/beta) | Small, unmyelinated (A-delta & C) | | Decussation Level | Medulla | Spinal cord (anterior white commissure) | | Lesion Deficit | Ipsilateral loss below lesion | Contralateral loss 1-2 segments below lesion |
Spinal cord cross-section with colors showing affected tracts. ascending and descending tracts of spinal cord ppt
Ascending tracts carry sensory information from body receptors to the brain. These pathways typically utilize a three-neuron chain (First-order, Second-order, and Third-order neurons) to reach the cerebral cortex. A. Posterior Column-Medial Lemniscal Pathway (PCML) Posterior funiculus.
Decussates almost immediately upon entering the spinal cord and ascends contralaterally (opposite side). – Detail Fasciculus Gracilis vs
Pain, temperature (Lateral); crude touch, pressure (Anterior). Anterior & Posterior Unconscious proprioception for coordination and posture. II. Descending Tracts (Motor Pathways)
A suggested PPT structure for this topic could include: temperature (lateral tract)
Fasciculus Cuneatus: Carries information from the upper limbs and upper trunk (above T6).
Transmits pain, temperature (lateral tract), and crude touch/pressure (anterior tract).
Resides in the dorsal root ganglion (DRG); collects sensory info from the receptor.
– Introduce Brown-Séquard, Anterior Cord, and Central Cord syndromes using diagnostic imaging or color-coded diagrams.