Understanding behavioural changes after an acquired brain injury: the nursing perspective

Behaviour isn't controlled by just one part of the brain. It's coordinated by a network with the frontal lobe and limbic system doing much of the heavy lifting. These are the areas responsible for impulse control, emotional regulation, motivation and reading social situations. They're also among the most affected regions in an acquired brain injury, whether the cause was trauma, stroke, infection, a lack of oxygen to the brain or another type of injury. 

When these networks are disrupted, the result isn't a change in character so much as a change in capacity. The person hasn't become someone new but the tools they once used automatically such as, pausing before reacting, reading a room or weighing up consequences, may simply be harder to access. Research into moderate-to-severe brain injury suggests behavioural changes are common, with studies estimating that anywhere from a quarter to the majority of people experience some shift in personality or behaviour, depending on how it's measured and the severity of the injury. 

For families, this distinction matters. Framing these changes as an injury-related loss of capacity, rather than a personal choice or a character flaw, is often the first step toward responding with patience rather than frustration. 

No two brain injuries look the same, so no two people will experience exactly the same changes. That said, these are some common patterns: 

• Irritability and lowered frustration tolerance: Small setbacks that wouldn't have registered before an injury can feel disproportionately overwhelming afterwards, leading to snapping, agitation or short fuses. 
• Disinhibition: Damage to the frontal lobe can loosen the usual social filters, leading to impulsive comments, actions or decisions that feel out of character. 
• Apathy or loss of motivation: Sometimes called adynamia, this shows up as difficulty initiating tasks or a flat, disengaged presentation that can be mistaken for laziness or depression. 
• Emotional lability: Rapid and sometimes intense shifts in mood. For example, laughing one moment, tearful or angry the next without an obvious trigger. 
• Anger, aggression and impulsivity: Outbursts are frequently tied to frustration over reduced physical or cognitive function, rather than being directed at the people nearby. 
• Reduced perspective-taking: The ability to consider someone else's point of view is a complex cognitive skill. This skill is commonly affected after an ABI, which can come across as self-centred behaviour even when that's not the intent. 

One of the most useful shifts a family can make is to stop asking "why are they doing this to me" and start asking "what is this behaviour trying to tell me."  

Every behaviour serves a purpose. An outburst might be frustration at not being able to find the right word. Withdrawal might be fatigue or overstimulation. Repetition of the same request might reflect memory difficulties rather than stubbornness. 

This is where the ABC approach, widely used by nursing and allied health teams, can help: noticing the Antecedent (what happened right before), the Behaviour itself, and the Consequence (what happened after). Over time, this pattern-spotting often reveals triggers such as noise, fatigue, pain, unfamiliar routines or feeling rushed, all of which can be adjusted to help improve the situation. 

Managing behaviour after ABI isn't about a single formula, because every person and every injury is different, but a few approaches consistently help: 

MSWA Neurological Liaison Nurses specialise in exactly this kind of support. Delivered through the MSWA NeuroConnect Nurse Program, our NDIS registered nurses bring specific training in neurological conditions to both the person with the ABI and the people around them. 

We deal with people right from their diagnosis all the way through their disease progression. So we're able to offer specialised care with our knowledge and the additional training we do to be able to meet their very specific and sometimes ever-changing needs,” Aline, MSWA Neurological Liaison Nurse.  

In practice, that looks like: 

Holistic clinical assessments and care planning: Rather than treating behaviour in isolation, our Nurses build a full picture of the cognitive, physical and emotional changes happening alongside it and develop a care plan around all of them together. 

A direct line when you need one: Our Nurse Support Service runs from 8:00am to 3:30pm, Monday to Friday, so families have somewhere to turn with questions about managing day-to-day changes, not just at scheduled appointments. 

Education, not just intervention: Our Nurses take the time to explain what's happening neurologically and why, so you're not left guessing at what you're seeing. 

Coordination across your whole care team: Where behavioural changes are tied to communication, routine or emotional wellbeing, your Nurse can coordinate directly with MSWA's Occupational Therapists, Speech Pathologists, Counsellors and Social Welfare team. 

Help navigating funding: Our Nurses can prepare nursing assessments and intervention summary reports to support NDIS funding applications, including access to Specialist Behaviour Support where it's needed. 

Because behavioural change so often overlaps with cognitive, emotional and physical symptoms, our Nurses work as part of a broader team rather than in isolation. This allows us to bring in the right specialist at the right time, rather than leaving families to work out who to call next. 

Supporting someone through behavioural change is emotionally demanding, and it's common for families to describe it as a kind of grief without a clear end point. Some mourn the person's previous personality while still caring for who they are now. Feeling exhausted, anxious or overwhelmed at times doesn't mean you're failing. It means you're carrying a genuinely heavy load and looking after your own wellbeing isn't optional. MSWA's Counselling and Wellbeing Service and peer support groups are there for family members and carers, not just the person living with the injury. 

Behavioural changes after an acquired brain injury can be some of the hardest changes to live with. For the person experiencing them and for the people who love them. But with the right understanding, support and care plan, many families find these changes become more manageable over time. 

MSWA's Neurological Liaison Nurses support people and families right across Western Australia, whether you're in Perth or a regional area. We can meet you in person, at one of our Service Centres, in your home or via telehealth. 

Get in touch with MSWA's Nursing team to find out how we can support you and your family through behavioural changes after an acquired brain injury.