Thinking and memory changes

Thinking and memory changes can be a normal part of getting older, but they may affect you more if you have Parkinson’s.

Key points

Parkinson’s can cause symptoms affecting thinking and memory. These can include trouble concentrating, multitasking or making decisions.
These changes may not affect your daily life too much. But they may make everyday tasks difficult.
If your symptoms are mild, your specialist may diagnose you with Parkinson’s with mild cognitive impairment. If they affect day to day activities, they may diagnose you with Parkinson’s dementia.
Around half of all people with Parkinson’s will experience some form of thinking and memory changes within 10 years of their diagnosis.
Physical activity, eating well and keeping up with social activities can help you live well with thinking and memory changes.
Visual prompts, sticking to a routine and thinking and memory aids can help with daily tasks.
Medication and reviewing your Parkinson’s drugs may also help.

You don’t need to read all of this information at once. You can skip to the sections that are most relevant to you, or read parts only when you feel ready.

problems planning or doing a few things at the same time (multitasking), or moving quickly from one task to another
problems with attention and concentration. You might find it difficult to do everyday activities such as reading a newspaper article from start to finish
difficulty using a computer or your mobile phone
slowness of thoughts. You might find it harder to make decisions or respond to questions.

Generally, these symptoms may not affect your daily life too much, but they might make you feel less organised. Or you may get confused, particularly if you’re stressed.

It’s important to remember that Parkinson’s affects everyone differently. Not everyone will experience these symptoms or have the same combination of symptoms.

If you’re experiencing these symptoms, your Parkinson's specialist may diagnose you with Parkinson’s with mild cognitive impairment.

If you’re worried about or are experiencing these symptoms, speak to your specialist doctor or Parkinson's nurse, as there may be positive steps you can take to improve them.

What happens if thinking and memory changes get worse?

For some people, their symptoms may get worse over time. But this doesn’t happen to everyone.

If you have thinking and memory problems that get worse and start to affect everyday life, including things like cooking, cleaning and dressing, then it’s important to speak to your specialist or Parkinson’s nurse. They can talk to you about useful things that you can do which could improve your symptoms.

Parkinson's dementia and dementia with Lewy bodies

Parkinson’s dementia and dementia with Lewy bodies

If your thinking and memory problems are serious enough to affect your ability to carry out everyday tasks, your Parkinson's specialist may diagnose you with Parkinson’s dementia.

Not everyone who experiences thinking and memory changes goes on to develop Parkinson’s dementia.

Parkinson’s dementia is very similar to another type of dementia, called dementia with Lewy bodies, and they share the same symptoms. These are the 2 main types of dementia that can affect people with Parkinson’s.

People with Parkinson’s dementia and dementia with Lewy bodies may experience the following symptoms.

Difficulty with visual and practical tasks. For example, reading clocks or putting on trousers correctly.
Slowness in thinking, such as difficulty finding the right words.
Trouble concentrating. This can affect how you talk or communicate with others.
Changes in thinking during the day. Sometimes being alert but other times being confused.
Changes to your sleeping patterns. For example, taking more naps during the day despite getting a normal amount of sleep, or falling asleep during meals.
Visual hallucinations (seeing something that is not there). Some people mistake objects for other things. For example, a pile of clothes might look like a dog.
Being less engaged. You may feel less interest in the activities you used to enjoy. This is called apathy.
Changes to how you feel, such as feelings of anxiety, depression or agitation.

You may find that symptoms fluctuate (change) from hour to hour, and day to day.

What’s the difference between Parkinson’s dementia and dementia with Lewy bodies?

The main difference is when you start experiencing symptoms. If you’ve had motor (movement) symptoms, such as tremor or stiffness, for at least 1 year before symptoms of dementia, specialists will often give a diagnosis of Parkinson's dementia.

If you get dementia symptoms before or at the same time as movement symptoms, specialists will usually give a diagnosis of dementia with Lewy bodies.

These 2 conditions are sometimes grouped under an umbrella term: Lewy body dementia. This can be useful as the 2 conditions have similar symptoms. Health professionals may use the term Lewy body dementia if it’s not clear exactly when the thinking and memory problems started.

The causes and ways of managing symptoms in Parkinson’s dementia and dementia with Lewy bodies are the same.

How is Parkinson’s dementia different from other dementias, such as Alzheimer’s?

Parkinson’s dementia is different from Alzheimer’s disease, although some of the symptoms are similar. People with Alzheimer’s have memory problems, which means they may repeat questions and conversations.

This is less common in Parkinson’s dementia. People with Alzheimer’s may also have trouble recognising their family and friends, which doesn’t usually happen in Parkinson’s dementia.

Will thinking and memory changes happen to me?

Thinking and memory changes are common in Parkinson’s. Around half of all people with Parkinson’s will experience some form of thinking and memory changes within 10 years of their diagnosis.

But this doesn’t mean you will go on to develop more serious problems. Everyone’s Parkinson’s is different. If you’re worried, you should speak to your Parkinson’s specialist. There are ways to improve symptoms or even slow the progression of these changes. So it’s helpful to recognise them early.

What causes memory and thinking changes?

Parkinson’s leads to physical changes in the brain. As Parkinson’s progresses, more brain areas are affected. One reason for this is that there are lower levels of a brain chemical called acetylcholine, as well as dopamine.

Another cause is that proteins can build up in the brain and affect different brain areas.

There’s still a lot of research happening to understand the brain changes that cause thinking and memory symptoms in Parkinson’s.

Why do some people get these symptoms, and others don’t?

It isn’t clear why some people are affected by these changes and others aren’t.

Research shows that some things might increase the risk of developing thinking and memory changes if you have Parkinson’s.

These are called risk factors. They include:

Age. People who are older when they are diagnosed with Parkinson’s are more likely to develop these changes.
Genetics. Researchers have found that some genes are linked with a higher risk of developing thinking and memory problems. One example is a gene called GBA.
Sleep changes. Some types of sleep changes are linked with higher risk of developing thinking and memory symptoms. These include moving or shouting out during sleep.
Depression. Depression is common in Parkinson's. Research has shown that it is also linked with a higher risk of developing thinking and memory problems.
Heart disease and stroke. These conditions can have an effect on the structure of the brain, which can affect thinking and memory. For this reason, lowering the risk of heart disease and stroke is important if you have Parkinson’s.

These risk factors are highly variable between people. This means that if you have one or more of these risk factors, it doesn’t mean that you will definitely develop thinking and memory problems. Many people living with Parkinson’s will never develop serious thinking and memory symptoms.

Other things can also affect your focus and concentration. It's important to know about these, as there are things you can do to manage them.

For example:

Anxiety and depression. These symptoms can have a big impact on your ability to think, remember and process information properly. They can also affect your attention span and concentration. It’s important to talk to your specialist if you’re experiencing anxiety or depression so that you can get treatment and support.
Poor quality sleep. If you’re feeling tired or run down, or you're not sleeping well, this can affect your thinking, concentration and memory. Talk to your specialist if you are having trouble with your sleep, as they may be able to recommend things that may help.
Hearing or visual loss. This will make it harder to respond to people and your surroundings. Using hearing aids, or treating visual loss, can improve thinking and memory symptoms.
Being unwell for other reasons. For example, constipation or infections can affect your thinking and memory and ability to concentrate. If you or your family notice a sudden change in your thinking or memory, speak to your GP or Parkinson’s nurse to see if they can rule these things out.

Talking to your specialist

If you’ve noticed changes in your thinking and memory, or are worried about developing symptoms, you should talk to your Parkinson’s specialist at your next appointment.

It's important to act early as there may be treatments that you can benefit from and things that you can do to improve your symptoms.

During your appointment, your specialist will ask questions to understand more about the changes you’re experiencing. You may find it helpful to keep a diary or write down your symptoms to help you to explain what has been happening.

You may be asked to do some assessments, such as drawing or copying simple pictures, writing a sentence, or taking a short thinking and memory test.

Your specialist may also carry out a physical examination, or arrange blood or urine tests.

Sometimes, symptoms like confusion can be caused by other conditions. So they will need to rule out any other potential causes. They may also arrange a brain scan.

If possible, it’s very helpful to bring someone who knows you well to your appointment. This can be your partner, family member or a friend. This will be helpful for your specialist, as they can also give information about the changes they’ve noticed.

If your specialist diagnoses you with Parkinson’s with mild cognitive impairment or Parkinson’s dementia, they may suggest:

a change to your current medication
starting new medication for your thinking and memory
extra support for you or your family, which might include health professionals who specialise in memory problems, support groups, or emotional support provided by charities. The type of support available will depend on where you live.

Questions to ask your specialist

It might be helpful to take some questions with you to your appointment.

For example:

What changes can I expect?
What can I do to slow the progression of thinking and memory changes?
What help can I get?
What help is available for my partner or family?
What things do I need to think about to plan ahead?

What to take to your appointment

Notes of the changes you’ve noticed.
A list of your current medications.
Your questions.
Someone who knows you well, if possible.

Lilla’s sister Jasmine was diagnosed with Parkinson's in 2020. She says:

"For me to help Jasmine, I thought, I am going on a journey with her through this. That’s how I started going to appointments with her and building trust. She had to feel comfortable making certain decisions and I was there to support her.

"Often, after an appointment, we will go to a coffee shop to discuss the appointment and any medication changes needed. The connection we built through this time was very important.

"Being in this journey together has strengthened our relationship."

How can I live well with thinking and memory changes?

Even if you’ve already started experiencing thinking and memory changes, there are things you can do to help manage symptoms.

Professor Rimona Weil, Consultant Neurologist at UCL, says:

"Some people believe that nothing can be done about thinking and memory changes in Parkinson’s. But that isn’t the case. There are several important steps that people can take for themselves to improve and even slow thinking and memory changes."

Being active

Being physically active is important for people with Parkinson’s. It’s especially important for managing thinking and memory symptoms.

Regular, moderate to vigorous physical activity may help improve your cognitive ability and help your brain to work more efficiently. It can also reduce the risk of anxiety and depression.

Physical benefits of being active include building stronger muscles and bones, better balance and reducing your risk of falls.

Being active can also reduce the risk of developing other health problems such as heart disease and stroke. These can affect thinking and memory, so reducing your risk of having one or more of them is important.

How much physical activity should I aim to do?

Physical activity can include everyday things you may already be doing like walking, gardening, and climbing the stairs. You should try to find activities that you enjoy to raise your heart rate and also some activities that focus on flexibility, balance, strength, and multitasking.

Ideally you should aim for 2 and a half hours of physical activity a week. This is around half an hour, 5 days a week. Scheduling activity each day at a specific time can create a habit, and make it easier to maintain. It can also be helpful and enjoyable to exercise with other people.

The most important thing is choosing something that you find enjoyable and achievable.

There are many exercise classes or groups for people with Parkinson’s.

Find a class or activity near you with our lookup tool.

Eating well

While there is no specific diet that's recommended for Parkinson's, having a healthy and balanced diet will improve your overall wellbeing and may even help your thinking and memory.

Visual prompts

Having calendars, clocks, noticeboards and notices around your home may help jog your memory.

Routine and being organised

Having a clear daily routine can be helpful. Being as organised as possible can help you stay focused and reduce stress.

You might find it helps to keep a list of things to do. You can see what you have achieved as you tick off each task.

Remember that sometimes it helps if you slow down and tackle one thing at a time, rather than trying to do several things at once.

Prioritise the things you have to do and the things you want to do, and choose which things you can leave for later.

Giving your full attention to whatever you’re doing can help you avoid mistakes. This can reduce stress and help you feel in control.

Thinking and memory aids

Try using a basket or box to keep things like your keys, wallet and glasses in one place.
Drug dispensers and pill timers can be a useful reminder to take your medication at the times set by your specialist or Parkinson’s nurse, to make sure it works as well as possible.
Keep a diary of your symptoms. This can help you explain any problems when you see your health professional.

Therapies and support services

There are many types of therapies and other support services that may be able to improve or help manage some of your symptoms. These include:

physiotherapy
speech therapy
occupational therapy
support from specialist mental health services, such as neuropsychology.

Your specialist and Parkinson's nurse can talk to you about what type of treatment is best for you.

Driving and insurance

If you’ve been diagnosed with Parkinson’s dementia and still drive, you must tell:

the Driver and Vehicle Licensing Agency (DVLA), or Driver & Vehicle Agency (DVA) in Northern Ireland
your car insurer.

If you’ve been diagnosed with Parkinson’s dementia, you may also need to tell your travel or life insurance company about your diagnosis.

Medication

If you’re diagnosed with Parkinson’s dementia, your specialist may review your medication. This is because some of the side effects of Parkinson’s medication can make the symptoms of Parkinson’s dementia worse.

But reducing the dose, or stopping these drugs, may mean that the movement symptoms of your Parkinson’s are not as well controlled as before. For this reason, treating the dementia symptoms needs to be balanced with managing your physical symptoms.

Your specialist will also talk to you about what medication might help.

Don’t stop or change your medication by yourself. Always speak to your specialist or Parkinson’s nurse if you’re having issues.

Medications that are often used to help in Parkinson’s dementia include:

Rivastigmine (also called Exelon and Prometax)

Rivastigmine belongs to a group of drugs called cholinesterase inhibitors. They stop the breakdown of acetylcholine in the brain.

Acetylcholine allows nerve cells to communicate with each other. Rivastigmine increases the levels of acetylcholine in the brain, and boosts thinking and memory.

Rivastigmine comes in 2 forms: a capsule, usually taken twice a day, and a patch that is put on once a day. For both of these, the dose is usually increased gradually over time by your specialist.

Rivastigmine can sometimes cause side effects. The most common side effects are stomach problems such as feeling sick, or diarrhoea. Occasionally, it can also cause trembling, slight worsening of Parkinson’s symptoms, or nightmares.

It can slow the heart rate, so your pulse will be checked before starting, and some people may have an ECG (a test which measures the electrical activity in your heart).

Donepezil (also called Aricept and Adlarity)

Donepezil is also a cholinesterase inhibitor, like rivastigmine, and works in a very similar way to boost thinking and memory. It is taken as a tablet, usually once a day.

Donepezil has the same side effects as rivastigmine, with some people feeling sick, or experiencing diarrhoea. It can make movement symptoms of Parkinson’s worse.

Similar to rivastigmine, it can also slow the heart rate, so a pulse check or ECG may be needed before starting.

Other medications that are sometimes used to help in Parkinson’s dementia include:

Galantamine (also called Reminyl and Razadyne)

Galantamine also acts by increasing the amount of acetylcholine in the brain. It’s taken as a capsule and causes similar side effects to rivastigmine and donepezil.

Memantine (also called Evixa, Nemdatine and Valios)

Memantine acts on a group of receptors in the brain called NMDA receptors. These help communicate nerve signals in the brain that help with learning and memory.

Memantine is usually taken as a tablet, once a day, and the dose is gradually increased over a few weeks. The most common side effect of memantine is sleepiness. It can also cause headaches and constipation.

How do I plan for the future?

If you have thinking and memory problems, or support someone who does, it’s important to try to plan for the future.

If your thinking and memory problems get worse, then having plans in place will make it easier to manage things like legal documents, money and your health.

Planning ahead can also reduce stress. These are some things to consider, when you feel ready.

Benefits and financial support

Feeling in control of your finances is very important for your wellbeing. You may be entitled to benefits, grants, loans and other support

Read our information on benefits.

Advance care planning

Advance care planning is a way to ensure you get the care you want at any stage. This includes at the end of life.

By thinking about the future and talking about what you want, you can be more in control about what lies ahead.

Read our information on your rights and legal options when preparing for the future.

You can also make your wishes known about your care using a process called ReSPECT, which stands for Recommended Summary Plan for Emergency Care and Treatment.

The ReSPECT process creates a personalised recommendation for your clinical care in emergency situations where you are not able to make decisions or express your wishes.

Power of attorney

Consider setting up a power of attorney. This means that you nominate one or more people that you trust to make decisions on your behalf about legal and health matters. This gives you more control and helps you to decide in advance what happens if you have an accident or an illness and can’t make your own decisions.

How you set up a power of attorney and what your attorney can do depends on where in the UK you live.

Read our information about setting up a power of attorney.

Should I tell other people?

It can be difficult explaining Parkinson’s to other people. This may be especially true if you’re experiencing thinking and memory changes. You may find it upsetting or not know what to say.

You may want to tell friends, wider family members or your manager at work about your symptoms.

There are some benefits about talking to others about these symptoms. It can:

make you feel more able to cope with any worries you have
help extend your support network
strengthen and build new relationships
help you to feel more in control
help to raise awareness and educate others.

These are some tips on how to approach conversations:

Be prepared. You may want to make a list of things you would like to say or think about questions that other people are likely to ask. You could have information booklets or webpages ready (like this one) to give others more information during conversations.
Make sure you’re comfortable. A relaxed environment is best, where you won’t be distracted. Some people may find it easier to talk when you are out walking or doing something where you are beside each other.
During the conversation, try not to rush. Remember that you can take time to think about your responses and take a break if you need to.
Think about how people might react during your conversation. People that you talk to may react in unexpected ways and some may not know how to react. Others may find the conversations upsetting. It's important to acknowledge this and take a break if needed.

Practical support for loved ones

You might be a family member, a partner, or a friend, providing care and support to someone with Parkinson's who has thinking and memory problems.

If you regularly provide support or care for someone with Parkinson’s dementia, you have a right to a carer’s assessment. This is done through your local authority.

After your assessment, if your local authority agrees you need support with daily tasks, such as dressing the person with Parkinson’s who you support, they will arrange services to help you. To find out more, contact your local authority or speak to your GP.

You may also be able to get financial support. This includes benefits like Carer’s Allowance and help with council tax bills.

Can I get involved in research?

Researchers are making a lot of progress in why thinking and memory changes happen in Parkinson’s.

Researchers are currently focusing on understanding more about:

the proteins that build up and how they affect the brain
why these changes happen
how to slow down the progression of symptoms, including better medications and treatments.

Researchers rely on people who are experiencing symptoms like thinking and memory changes to understand why they happen and make progress. You are the expert. The more people that take part in research, the more we will learn about the condition.

You can get involved in research in many ways. This could include:

volunteering for studies and clinical trials
giving blood for genetic research
sharing your views on the healthcare you receive through questionnaires.

It’s possible to get involved in some types of research from home.

Find out more about taking part in research projects.

Professor Rimona Weil, Neurologist and Neuroscientist at UCL, says:

"Current research is looking at why people with Parkinson’s often have such different symptoms. It’s possible that different people with Parkinson’s have different proportions of these proteins building up. We hope that if we can understand this better, then in future, when new treatments are developed, we will be able to target the right treatment to each individual person with Parkinson’s."

How we developed this information

This information was co-developed as part of a multidisciplinary project, led by Professor Rimona Weil. The project, Patterns of Perception in Parkinson’s (PoP-PD), was co-developed with people living with Parkinson’s, other experts and Parkinson’s UK. Professor Weil is a Neurologist at the National Hospital for Neurology and Neurosurgery, and Neuroscientist at UCL.

Our helpline and other useful contacts

Call our helpline free on 0808 800 0303 for advice on thinking and memory changes or any aspect of living with Parkinson's.

Alzheimer’s Society offers Information, advice and support for people with dementia and their families. Visit the Alzheimer’s Society website.

Dementia UK (Admiral Nurses) provides support for families facing dementia through their dementia specialist nurses. Visit the Dementia UK website.

The Lewy Body Society provides Information and resources on Lewy body dementia. Visit the Lewy Body Society website.

Alzheimer Scotland provides support to people living with dementia in Scotland. Visit the Alzheimer’s Scotland website.

Get this information in other formats

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Take part in research

UK research teams are studying whether ondansetron can effectively treat hallucinations in Parkinson's and Lewy Body Dementia.

If successful, this affordable, already licensed drug could become available to patients within a few years.

Find out more about this research

Last updated 4 August 2026

This content will next be reviewed within 3 years of that date. If you'd like to find out more about how we put our information together, including references and the sources of evidence we use, please contact us at [email protected]