A 62-year-old woman from Tamil Nadu presents with acute onset of vertigo, nausea, vomiting, and loss of pain and temperature sensation over the left side of her face and right side of her body. On examination, she has left-sided Horner syndrome (miosis, ptosis, anhidrosis), nystagmus, and ataxia. MRI shows an acute infarct in the left lateral medulla. Which of the following structures are damaged in this classic brainstem syndrome?