Dementia and behaviour change- Photo of an older man with white hair and glasses looking down at the camera no smiling. He wears a blue business shirt.

Dementia and behaviour change

When you or a loved one receives a diagnosis of dementia, it can take some time before symptoms become obvious to others. But over time, it’s extremely likely that a person with dementia will experience changes to their usual behaviour.

While forgetfulness and occasional confusion are fairly easy to cope with, sudden or inexplicable shifts of mood or erratic behaviour can become increasingly upsetting for all involved.

Here are some of the most common forms of behaviour change experienced by those with dementia, as well as strategies to address them.

‘Sundowning’ and anxiety

While the cause is not fully understood, becoming anxious, more disoriented or confused is very common in the late afternoon and early evening for those with dementia.

Some common ways to address this include:

  • Encouraging rest in the early afternoon
  • Engaging in familiar, comforting and predictable early-evening activities
  • Avoiding bright lights, loud noise and busy activity.

These techniques don’t work for everyone, or every time. Use trial and error, but always discuss the situation with a doctor, and consider medication if needed.

Never attempt to physically restrain someone. Safe pacing may help, and accompanied walks may also calm things down.

Agitation, aggression and false ideas

Often the most upsetting symptom for carers is rapid mood changes and bouts of anger. When this is coupled with delusional ideas or even hallucinations, it can be extremely difficult for carers to manage.

Some common ways to address this include:

  • Not arguing or disagreeing. Acknowledge the distress the feeling must be causing.
  • Acknowledging and then ignoring delusions that cause no harm or anxiety
  • Reminding the person of familiar things: the house, objects, music, etc.
  • Increased lighting and physical touch may help; but check first that these changes are welcome.

Some people hide belongings or put them ‘away’ in unusual places. It’s not uncommon for them to later believe these items have been stolen. Try to locate common hiding places, and happily ‘find’ things there.

It’s important for the wellbeing of the carer that they not take things personally. Not easy! Reach out and seek help from doctors, social workers or dementia support groups.


Wandering is a common and worrying activity for people with dementia. Dementia Australia lists more than 10 possible causes of wandering, spanning everything from boredom through disorientation to a confusion between daytime and night-time. There are obvious dangers associated with wandering.

Some common ways to address this include:

  • Ensuring people are able to be identified if they do wander; typically through an identity or Medic Alert bracelet
  • Notifying neighbours or local shop owners. It might seem like an inconvenience, but people are almost always willing to keep an eye out.
  • Identifying any pattern, trigger, time of day or path with wandering. A diary can help if wandering becomes frequent.

If someone does wander, don’t panic. Check the property, ask neighbours, do a quick drive around the area (including any frequently-visited locations) and then don’t hesitate to contact the police.

When your wandering loved one returns, don’t be angry or emotional. Be calm, comforting and supportive. They have probably felt afraid and may be embarrassed.


Not surprisingly depression – both in its common and clinical definitions – affect people with dementia at a higher rate than the general population. Whether it’s a decline in mood caused by changes in health, outlook or relationships, or a syndrome that overrides typical mood over a longer period of time (sometimes with no identifiable cause), depression can hit up to 30% of people living with dementia.

Dementia shows itself in many ways: fatigue, lack of interest, withdrawal from social situations, diet changes, poor sleep, emotional mood swings and more.

Some common ways to address this include:

  • Be positive. Praise helps!
  • Consult a doctor. Medication usually helps.
  • Be careful of large group situations
  • Don’t expect too much of someone with depression.


A symptom that can be extremely confronting and embarrassing (especially for carers, and – later – for the person involved) is the loss of inhibition, especially in social and public situations.

It might look like rude or offensive talk, exposure of body parts, inappropriate physical touching and similar behaviours. It is frequently sexual.

Disinhibition and confusion can result in a person with dementia treating a stranger or a child like a spouse. It can also result in not understanding how or where to use a toilet.

Some common ways to address this include:

  • Reacting with patience and compassion. If in public, simply explain the situation. Most people will be understanding and helpful.
  • Finding opportunities to distract, or change the subject. Retain a sense of humour.
  • Consulting a doctor to see whether any medications could be contributing to the situation.