The presence of tongue bite marks and post-ictal confusion strongly indicates a seizure as the cause of unconsciousness. Tongue biting, especially on the lateral edges, is characteristic of generalized tonic-clonic seizures due to violent jaw movements. Post-ictal confusion reflects the brain’s transient dysfunction following seizure activity. Other options like pinpoint pupils, neck stiffness, and decerebrate posturing suggest different etiologies (e.g., opioid toxicity, meningitis, or severe brain injury) rather than seizure. Therefore, these clinical signs help differentiate seizure-induced unconsciousness from other causes.

Reference: Adams and Victor’s Principles of Neurology, Ropper and Samuels, 11th Edition.