The mammalian spinal commissural system: properties and functions.

Area of Science:

• Neuroscience
• Motor Control
• Spinal Cord Research

Background:

• Commissural systems are vital for coordinating left-right skeletomuscular activity.
• These systems are present throughout the neuraxis, including the spinal cord.
• Commissural interneurons are key components of the mammalian spinal cord.

Purpose of the Study:

• To review the properties and functions of mammalian spinal commissural interneurons.
• To highlight the heterogeneity and classification challenges of these interneurons.
• To explore their role in motor circuits, including locomotion, posture, and goal-oriented behaviors.

Main Methods:

• Review of existing literature on spinal commissural interneurons.
• Analysis of criteria used for defining and classifying these cells (location, projections, phenotype, etc.).
• Discussion of functional roles based on current research.

Main Results:

• Commissural interneurons are diverse and influence various spinal circuits.
• Their contribution to locomotion and posture is established, but roles in complex behaviors are less clear.
• Limited data exists on primate cervical spinal cord commissural interneurons.

Conclusions:

• Commissural interneurons exhibit distinct properties based on their location and characteristics.
• Further research is needed, particularly in primates, to fully understand their function in complex motor tasks.
• Understanding these interneurons may offer insights into restoring function after spinal cord injury and stroke.