Alzheimer's disease is the most common cause of dementia. It develops gradually, so the first changes are often attributed to age, fatigue, stress, or personality traits. Meanwhile, scientists are studying a range of behavioral changes that may accompany various types of dementia long before noticeable memory decline. It is important to note that some of the symptoms described below are more characteristic of other forms of dementia, particularly frontotemporal dementia, rather than Alzheimer's disease. ## 1. Changed Sense of Humor A person who previously enjoyed subtle jokes suddenly begins to laugh at primitive, absurd, or even inappropriate things. They may find amusing situations that others do not find funny at all. Researchers at University College London studied changes in humor among people with various types of dementia. Relatives of some patients noted that these changes appeared years before a diagnosis was made. Changes in humor can be particularly noticeable in certain forms of frontotemporal dementia. Therefore, it is not the fact that a person enjoys simple or absurd humor that should raise concern, but **a sharp and atypical change in preferences**, especially when combined with other behavioral changes. ## 2. Deterioration in Self-Care Another possible signal is changes in the usual attitude toward appearance. A person who previously paid careful attention to their clothing may start wearing outfits that are completely inappropriate for the weather or situation. For example, going outside in overly warm clothing in the summer or, conversely, not dressing adequately in cold weather. They may stop noticing stains on their clothes, unbuttoned buttons, or other details that they would have previously paid attention to. The cause of such changes may be impairments in memory, attention, planning, and the ability to assess situations correctly. But here, too, it is important to consider the context: sloppiness in itself is not a sign of Alzheimer's disease. What matters is a noticeable change in the person's usual behavior. ## 3. Driving Problems Changes in cognitive functions can affect the ability to drive. A person may find it increasingly difficult to navigate even familiar streets, maintain distance, react quickly to traffic situations, or park correctly. Sometimes a driver starts using a navigator much more frequently on routes they previously knew well. Researchers are indeed studying driving behavior as one potential way to identify early cognitive changes. Particularly concerning are situations where an experienced driver suddenly begins to regularly confuse routes, make unusual mistakes, or get lost in well-known areas. In such cases, the issue concerns not only the health of the individual but also the safety of other road users. ## 4. Unusual Generosity and Financial Problems Financial behavior can also change with cognitive impairments. For example, a person who was previously cautious with money suddenly begins to make impulsive purchases, give away large sums, trust strangers, or agree to dubious offers. Research links certain cognitive impairments to a decreased ability to assess financial risks and the intentions of others. This is particularly dangerous because elderly individuals become more vulnerable to fraudsters. One should be concerned if the changes occurred unexpectedly: a person who was always frugal and cautious now transfers money to strangers or makes financial decisions that are completely uncharacteristic of them. ## 5. Loss of Usual Speech and Social “Filters” A person suddenly begins to curse more often, make tactless remarks, or say things they would never have allowed themselves to say out loud before. Such changes may be related to impairments in the areas of the brain responsible for self-control and social behavior. The loss of social inhibitions is particularly characteristic of certain variants of frontotemporal dementia. It is not just about profanity. Overall behavior may change: a person interrupts others, violates personal boundaries, engages in inappropriate actions, and does not understand why their loved ones find their behavior strange. Therefore, unexpected rudeness or profanity does not allow for a diagnosis. Much more important is a sharp change in personality and the loss of previous control over behavior. ## When to Really See a Doctor Neither a love for simple comedies, nor a failed parking attempt, nor an occasional rudeness means that a person is developing Alzheimer's disease. Such changes can occur for a variety of reasons — from stress and lack of sleep to medication, depression, and other illnesses. What should raise concern is primarily a persistent and progressive change in usual behavior, especially if memory, orientation, speech, planning ability, or the ability to handle daily tasks deteriorate simultaneously. In such cases, it is better to consult a doctor to determine the cause of the changes rather than trying to self-diagnose. The first manifestations of cognitive impairments do not always begin with forgotten names or lost keys. Sometimes, character, financial behavior, speech, sense of humor, or everyday skills change earlier. The key is to assess not a single oddity but the overall pattern and dynamics of changes: if a person has noticeably become “not themselves,” it is a reason to discuss the situation with a specialist.
