A 69-year-old man is evaluated for a 1-year history of increasing word-finding difficulties. The patient also reports occasional difficulty recalling names of objects and people and has had problems comprehending conversations. His daughter reports sometimes not understanding what her father is saying because of his frequent use of filler words, such as “that thing” and “you know”; she says that otherwise his mind seems sharp, his cognition unimpaired, and his memory excellent. He has no other significant medical history, and he takes no medication. His older brother had onset of dementia at age 56 years, and his father developed dementia at age 60 years.

On physical examination, vital signs are normal. General physical examination results are unremarkable, and a neurologic examination yields no focal findings. However, the patient has trouble answering even simple questions about where he lives or what he had for breakfast and is unable to name simple objects.

Results of laboratory studies, including a complete blood count, comprehensive metabolic profile, and thyroid function studies, are normal.

An MRI of the brain is normal.

Which of the following is the most appropriate next step in management?