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Behavioral & Personality Changes

Many people with dementia may act in ways that are very different from how they used to be.  They may say an offensive or rude comment that they would have never said before–or other times, they may do things that do not make sense to others. These behavioral changes are often the most difficult and distressing part of the disease as it affects not only the person but also family and friends.

In general, behavior can change for many reasons but in dementia, it is usually a slow process due to brain cells that are dying in particular areas of the brain. The behavior changes that are seen often depend on which part of the brain is losing cells.

For example, in Alzheimer’s disease, the part of the brain that is affected is the medial temporal lobes, or more specifically, the hippocampus and related memory circuit. This area is important for forming new memories and for learning and retaining new information. In a person with Alzheimer’s disease, this may present as forgetting recent events, misplacing personal items, repeating the same stories, or asking the same questions repeatedly. As the memory problems get worse, the person with Alzheimer’s disease may become suspicious or even paranoid if they forget where they put something—for example, if they forgot where they put their wallet or eyeglasses. In their mind, no other explanation seems to make sense. This is an example of how the brain ‘fills in’ the memory gaps and how paranoia/delusions are often associated with progressive memory loss in a person with Alzheimer’s disease.

Similarly, many of the other behavioral changes seen in dementia have neurobiological origins. As such, it is important to remember that it is these brain changes that are affecting how the person understands the world around them–and why they may seem to experience a reality that is very different from yours and misunderstand what is happening around them.

Some of the most common emotional and behavioral changes associated with dementia are:

  • Depression –Low mood, tearfulness, feelings of failure or guilt, hopelessness, and thoughts of death or suicide.
  • Apathy/Indifference – Less interested in usual activities or in the activities and plans of others. May require prompting to take part in hobbies or pastimes which he/she used to enjoy.
  • Disinhibition – Acting impulsively without thinking. For example, approaching strangers and talking to them as if he/she knows them, or saying things that may hurt others feelings.
  • Euphoria – Acting excessively happy or appearing to feel too good for no apparent reason.
  • Anxiety – Appearing tense and unable to relax. When people get anxious, they often feel their heart beating fast or they start shaking or sweating or can’t catch their breath. In dementia, this may occur when separated from caregiver, or in attempting to avoid certain situations if they previously caused anxiety.
  • Irritability– Losing temper and appearing cranky and impatient. Difficulty coping with delays or waiting for planned activities.
  • Agitation & Aggression –Emotional or angry outbursts. May occur when resisting those trying to help. May hit, push, throw things or use hostile words.
  • Eating and Dietary Habits – Changes in the types of foods that are preferred, losing, or gaining weight.
  • Nighttime Behaviors– Difficulty falling asleep or staying asleep throughout the night. “Sundowning” where behavioral symptoms peak in the evening. Wandering or pacing in the middle of the night. Acting out of dreams and moving during sleep. The following day, may take excessive naps during daytime.
  • Motor or Repetitive Behaviors –Doing things repeatedly, such as opening and closing doors or drawers, hoarding unnecessary items, becoming obsessed about something and not being able to let go of a particular topic. 
  • Hallucinations – False visions or voices. Seeing or hearing things that do not exist.
  • Delusions – Believing something that is not real or true, such as thinking family members have been replaced by impostors, that spouses have been unfaithful, that personal items have been stolen, or that someone has invaded the house.

What if my family member’s behavior changes suddenly (over hours or days)?

Contact your doctor or nurse.  It could be delirium. If the person’s behavior changes suddenly, do not assume that behavior and personality changes are always due to dementia. It could mean they have an infection or another medical problem that requires treatment. That’s because symptoms of dementia often get worse when people get infections, especially bladder or lung infections.

Are there medications that can help with the behavior changes?

Yes, but medications are not always the answer. Talk to your doctor about whether the benefits of a particular medication outweigh the risks in order to manage the behavioral symptom that is causing distress. It is important to know that some behaviors simply cannot be ‘’fixed’’ with medications.  Some medicines can also cause side effects and actually make things worse, so we must be careful with which medications we use.

Communication & Behavior: 10 Tips for Caregivers

  1. Try not to argue or confront the person with dementia when they express mistaken ideas or facts. Arguing or trying to convince a person of “the truth” is a natural reaction but it can be frustrating to all and can trigger more behavioral changes. Try to change the subject or gently remind the person of an inaccuracy.
  2. Think of behavior as a form of communication. People with dementia may become angry or anxious, but it’s a way of telling others that they may be in pain, confused, or scared of something.
  3. Try to be patient and calm. Repetitive questions, behaviors, or statements can be challenging to deal with as a caregiver. Try to speak slowly, present only one idea at a time, and be patient when waiting for responses. People with dementia are often very aware of non-verbal signals such as facial expressions, body tension, and mood. So if you are angry or tense, they may become annoyed, angry, or tense too.
  4. Try to analyze the behavioral change and identify what may be contributing. Was there a trigger or something that happened right beforehand? Was there a change to the home environment? Something as simple as rearranging furniture can cause someone with dementia to become frightened as they encounter something that is unfamiliar to them and different from their regular routine.
  5. Consider whether the behavior is dangerous or just frustrating. If the behavior is dangerous or puts themself or someone else at risk, it will require an active response on your part (for example, if the person gets angry and leaves the house impulsively and in an unsafe manner–you should walk with them and try to calm them down, and later install locks on the door). But it’s important to remember that if the behavior is simply annoying or frustrating, then it may require no response on your part. For example, if the person paces in the house but is calm and safe, then it may be best to work on accepting that the pacing is OK. See #6.
  6. Foster an attitude of acceptance. Remember that the behavioral changes are due to real neurobiological changes in the brain and are not because the person is deliberately trying to be difficult.
  7. Establish calm and consistent nighttime routines. Behavioral problems are often at night. Leave a nightlight on in the person’s bedroom if needed. Try to limit daytime naps.
  8. Try to create a daily routine that is structured and predictable for the person with dementia. Routine is an important source of comfort.
  9. Review caregiver training videos. These are available online and free. These videos can provide practical tools that you can use toward understanding and managing challenging behaviors (for example, what to do if they refuse medications)
  10. Talk to other caregivers. It can help to talk with other people who understand what you are going through. Consider joining a support group for people caring for loved ones with dementia.