✒️ Title: Sensory Pathways

🌟 Cues

• What are the basic functions of the ascending tracts in the spinal cord?
• Where are the sensory nuclei located in the grey matter of the spinal cord?
• Which tracts are responsible for fine touch, proprioception, and pain?

🗒️ Notes

• Ascending tracts in the spinal cord carry sensory information to the brain.
• The posterior grey horn contains sensory nuclei that receive sensory input.
• Key tracts include:
  • Fine touch, vibration, and proprioception: Gracile and Cuneate tracts.
  • Pain and temperature: Lateral Spinothalamic tract.
  • Crude touch and pressure: Anterior Spinothalamic tract.
• First-order neurons are located in the Dorsal Root Ganglia, synapsing in the spinal cord or brainstem.
• Second-order neurons decussate (cross over) and continue to the thalamus.
• Third-order neurons relay information to the somatosensory cortex in the postcentral gyrus.

📝 Summary

The sensory pathways in the spinal cord consist of ascending tracts that carry information such as touch, proprioception, pain, and temperature to the brain. These tracts are organized into different segments of the grey and white matter, with first-order neurons in the Dorsal Root Ganglia, second-order neurons in the spinal cord or brainstem, and third-order neurons in the thalamus. The integration of sensory input occurs in the somatosensory cortex. Various tests like pin-prick and vibration tests help assess the functioning of these sensory pathways.