Almost all people living with dementia will experience changes in behaviour or personality. These changes are particularly noticeable in dementias that affect people at a younger age, such as fronto-temporal dementia. They may include increased irritability, impulsivity, withdrawal, repetitive behaviours, or a reduced sense of empathy or tact. It can be confronting and confusing when someone you know well begins to act differently or in ways that seem out of character. These changes can appear at different stages of dementia and will shift over time. The unpredictability of these changes can make it especially hard for carers and families to adjust and cope.
It helps to remember that these changes are caused by changes in the brain, not deliberate choices. Understanding the reason behind the behaviour can make it easier to respond with patience and compassion.
Recognising triggers
Changes to behaviour, or the way people act and react often have triggers. A trigger is something in the environment, an emotion or physical feeling that prompts a reaction. Fatigue, pain, frustration, sensory overload, or feeling rushed can all be triggers. Keeping a note of what happened immediately before a concerning behaviour. For example, think about what was going on in the environment, like noise, what was being said or done, who was around, when (e.g. time of day) and where changes occur. Understanding triggers ( things that happened to provoke a behaviour) can help you identify patterns and prevent situations that make things worse.
Communication makes a difference
Sometimes behaviour change stems from difficulties communicating. The person may not be able to find the right words, express discomfort, or explain what they need. They may not understand what is being said or asked of them.
Simplifying language, giving extra time to respond, asking one thing at a time, or give one instruction at a time can make conversations easier and less frustrating for both of you. When having a conversation try to limit other distractions – like the TV or radio.
Supporting emotional wellbeing
Depression, anxiety, apathy, and agitation are also common in dementia. These are not just ‘moods’ but symptoms that deserve attention and treatment. Encourage regular physical activity, social contact, and enjoyable routines. Talk to your GP about non-drug approaches such as music therapy, exercise programs, or psychological support. Medication may also help in some cases but should be reviewed regularly (see Section 3.6 Medication).
Looking after yourself as a carer or supporter
Behaviour and personality changes can take a toll on relationships. It can feel like you are losing parts of the person you knew. These feelings are valid and normal. Seeking support–through counselling, peer groups, or respite care, can make a real difference.
Remember, supporting someone with dementia is not about controlling their behaviour but about understanding and adapting to the changes together. Small adjustments to routines, environment, and expectations can go a long way in improving daily life for both of you.
James, 56, lives with frontotemporal dementia. He has started making blunt or inappropriate comments to strangers (for example, “You’re fat” or “You walk strange”), reflecting changes in social awareness caused by his dementia. These situations were distressing for his family and sometimes led to frustration and raised voices, which only increased James’ distress. After contacting Dementia Support Australia, the family learned why these behaviours were happening and developed practical strategies, such as going out at quieter times and responding calmly.
With better understanding and support, outings became less stressful for everyone.
Changes in behaviour are part of the illness, but are often managed with support
Dementia Support Australia offers targeted assistance for managing behavioural changes at home or in residential care settings. Anyone can make a referral.
This page from Dementia Australia gives more information about the types of behavioural and mood changes and ways to manage. This page has a 30-minute comprehensive expert webinar from dementia expert Professor Henry Brodaty on behavioural change.
Photo: Malachi Cowie via Unsplash.
