Thoracolumbar preganglionic neuron cell bodies are located in which spinal regions?

• A. Thoracic and lumbar regions
• B. Cervical and thoracic
• C. Sacral and coccygeal
• D. Brainstem

Answer: (A)

The sympathetic division has a thoracolumbar outflow, meaning its preganglionic neuron cell bodies are located in the spinal cord segments from the upper thoracic to the upper lumbar levels. Specifically, these cell bodies sit in the intermediolateral cell column of the gray matter from roughly T1 to L2 (with some sources including adjacent segments). That makes the thoracic and lumbar regions the correct location for thoracolumbar preganglionic neurons.

The other regions listed correspond to different parts of the autonomic system. Brainstem houses parasympathetic preganglionic neurons that travel with cranial nerves III, VII, IX, and X. The sacral region (S2–S4) contains parasympathetic preganglionic neurons that form the pelvic splanchnic nerves. The cervical region does not contain sympathetic preganglionic cell bodies.