A 72-year-old retired accountant is brought to the clinic by his daughter, who is concerned about his memory. Over the past year, he has repeatedly forgotten recent conversations and misplaces his keys more often. He can still balance his checkbook, manage his medications, prepare meals, and drive without incident. He has no mood changes or loss of interest in activities. Neurologic and general physical examinations are unremarkable. A Montreal Cognitive Assessment (MoCA) yields a score of 24/30, with deficits primarily in delayed recall. Brain MRI shows age-appropriate cortical atrophy and no infarcts. Which of the following best characterizes this patient’s cognitive status?