Final answer:
A victim with a hemisection of the thoracic spinal cord would display loss of fine touch sensation ipsilateral to the injury and loss of pain sensation contralaterally below the level of injury.
Step-by-step explanation:
After a motorcycle accident resulting in a hemisection of the thoracic region of the spinal cord, a victim is likely to display distinct sensory deficits in terms of touch and pain. Speculatively, loss of pain sensation would be expected on the contralateral side (opposite to the injury) below the level of injury due to the crossing of pain fibers in the spinal cord. Conversely, the loss of fine touch sensation would occur on the ipsilateral side (same side as the injury). This is because the pathways for fine touch ascend ipsilaterally within the dorsal columns and are not affected by the hemisection. In comparison, the perception of pain stimuli would remain on the side with motor function, as the fibers crossing over would be interrupted by the hemisection. Imaging technologies such as MRI or CT scans are also helpful, but simple tests with tools like a cotton-tipped applicator can provide immediate insight into the level and extent of spinal damage, critical for making decisions about patient movement and management at the scene of the accident.