Final answer:
The lateral horns are part of the spinal cord gray matter critical to the sympathetic division of the autonomic nervous system, and are found in the thoracic, upper lumbar, and sacral regions.
Step-by-step explanation:
The lateral horns of the spinal cord are found within the gray matter in the thoracic, upper lumbar, and sacral regions. These horns are a crucial component of the sympathetic division of the autonomic nervous system, also known as the thoracolumbar system due to the location of central neurons.
The lateral horns contain the cell bodies of motor neurons which project to the sympathetic chain ganglia located adjacently to the vertebral column. This system has a significant influence on numerous organ systems throughout the body.