Cognitive impairment

1. A 65-year-old male presents with a 2-year history of forgetfulness. He needed to make more reminder notes and alerts on his smart phone to be on schedule. He is in charge of managing a small business, and noticed he cannot easily recall the names of new clients. Otherwise, the business is running well, and his decisions remain sound. His family and colleagues have noticed his struggles with recall but there have not been any changes in his performance. There was no significant past medical or surgical history. His mother had dementia in her senior years before she died from pneumonia. The neurological exam was normal including a full score on the Mini-Mental State Exam. On the Wechsler memory scale, he scored slightly lower than the controls and additional neuropsychological assessments revealed normal performance of the remaining cognitive domains. What is the most likely diagnosis?