Q. A 60-year-old woman is brought to the physician by her husband because of a 1-month history of memory problems. Her husband reports that she has difficulty walking and that she has fallen multiple times during this period, in addition to having several jerky movements that resolved spontaneously. She has a history of brain surgery to get rid of a benign tumor 12 years ago. On clinical examination, she is alert but does not respond to the physician. Which of the following will be found in this condition?