What matters is a persistent and unexplained change in judgment.
Financial behavior can be particularly important. Unusual purchases, repeated payments, difficulty understanding familiar financial arrangements, or susceptibility to scams may signal that something has changed.
Because financial problems can have serious consequences, unexplained changes in this area should not simply be dismissed.
8. Withdrawal From Work or Social Activities
Another possible sign is losing interest in activities that once mattered to the person.
Someone who previously enjoyed meeting friends, attending community events, gardening, cooking, playing games, or participating in hobbies may gradually stop doing them.
This can happen because cognitive tasks have become more difficult.
A person may avoid social situations because they are embarrassed about forgetting names or struggling to follow conversations. They may stop participating in hobbies because the activity no longer feels manageable.
However, social withdrawal is not specific to dementia.
Depression, anxiety, grief, loneliness, chronic pain, physical illness, and major life changes can all cause someone to withdraw from activities.
For that reason, this symptom is most meaningful when it occurs alongside other changes in memory, reasoning, communication, or everyday functioning.
9. Changes in Mood, Personality, or Behavior
Unexpected changes in personality can sometimes accompany cognitive decline.
A previously calm and patient person may become unusually suspicious, irritable, anxious, fearful, or emotionally unpredictable.