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The thoracic vertebrae levels associated with visceral sensation from the head and neck are indeed T1-T4. The primary rationale is that these levels correspond to the sympathetic innervation that arises from the upper thoracic sympathetic ganglia, specifically the paravertebral sympathetic chain.

Visceral sensation from the head and neck is primarily carried by the vagus nerve (cranial nerve X) and other cranial nerves. The thoracic spinal cord segments T1 to T4 provide the sympathetic outflow that innervates structures in the head, neck, and upper thorax. Therefore, these levels are involved in relaying autonomic information and visceral sensations from the upper areas of the body back to the central nervous system.

Lower thoracic levels are not involved in head and neck sensations, as they predominantly correspond to the thoracic and abdominal viscera innervation rather than the structures of the head and neck. Hence, T1-T4 is the appropriate range for this visceral sensory input from the head and neck region.