Dementia and Vision Problems

Dementia and Vision Problems

This factsheet considers some specific visuoperceptual difficulties that people with dementia can have, and possible ways of helping them. Understanding potential perceptual problems and intervening with appropriate help, support and reassurance can greatly assist people with dementia to feel safe in their changing perceived reality.

People with dementia can experience a number of visuoperceptual difficulties due to normal ageing, eye conditions, and sometimes from additional damage to the visual system caused by specific types of dementia.

Vision difficulties can result in a variety of ‘visual mistakes’ (including illusions, misperceptions, misidentifications and sometimes even hallucinations). They can cause a person with dementia to misinterpret their environment and what is in it. The consequences of such difficulties can be more severe for people with dementia than for people without, since they may not know (or remember) that they are making ‘visual mistakes’, or be rational or able to ‘test reality’ accurately. They may also have difficulty explaining what they have seen.

Visuoperceptual difficulties have been reported for a number of dementias including Alzheimer’s disease, dementia related to Parkinson’s disease, Lewy body dementia, and vascular dementia (if stroke-type damage is on or near to the visual pathway in the brain). Of the various types of dementia, the visual difficulties in Alzheimer’s disease have been most studied to date.

Visual perception is complex since, whether people have good vision or not, they try to interpret and understand what they see. Sometimes trying to understand what was ‘poorly seen’ involves making a ‘best guess’ at what was seen. If what we perceive seems real to us, it can directly affect our behaviour.

Accurate Perception

Although ‘vision’ usually refers to seeing with the eyes, and ‘perceiving’ refers to making sense of the information that the eyes (and the other senses) are receiving, the two words are often used interchangeably.

To perceive accurately requires the ability to co-ordinate all the components of the visual system (eyes, optic muscles, retinas, optic nerve) and process information from other senses and thoughts. It also depends on overall health of the body, visual system and brain, alertness, mood, motivation and even the expectation of what ‘should’ be seen. Accurate vision also requires the co-ordination of every aspect of our cognitive (thinking) ability to manage and make sense of visual information (Jones G M M et al, 2006a).

There are many components to vision: adjusting and maintaining optimal focus; adjusting to different light levels; perceiving depth of field, black and white, colour, lines, objects, faces; distinguishing between faces; separating objects from background; making the accurate small eye movements required to follow moving objects and scan information. There are also many possible types and combinations of visual difficulties.

Advances in the neuroscientific understanding of normal vision are helping to better understand visual changes resulting from ageing, use of medication, illness or injury, and specific types of dementia.

Normal Age-related Changes in Vision

Visual changes resulting from normal ageing can include:

§  reduced visual acuity (sharpness – nearby objects become blurred first)

§  an increase in the amount of light needed to see

§  an increase in the negative effects of glare

§  more time required to adapt to marked changes in light level (from dark to light or vice versa)

§  a reduction in size of the peripheral visual field

§  decreased contrast sensitivity

§  decreased depth perception

§  changed colour vision (increased colour saturation required to see colours – gradual loss of the blue/violet part of the colour spectrum – dark colours and pastel shades become increasingly difficult to distinguish between)

§  changes in the small eye movements (used to track moving objects, orientate oneself in new locations, and to read)

§  blurring from ‘floaters’ (clumps of cellular debris in the vitreous humour gel in the eye)

§  light flashes or momentary distortion of images (when vitreous humour in the eye begins to pull away from the retina)

§  decreased ability to perceive the flickering of strobe lighting.

Most people have regular sight tests and adjust automatically to their changing vision as they get older. They can use glasses, accurately problem-solve, or learn to compensate for visual changes. However, people with dementia, increasingly, may not be able to do this.

Illnesses, Drugs, and Medications Can Affect Vision

As well as the effects of normal ageing on the visual system, a number of visual disorders are commonly associated with ageing. These include cataracts, glaucoma, macular degeneration and retinal complications from diabetes. These can all result in changes such as blurring, partial loss of visual field, through to genuine visual hallucinations and complete blindness.

Use of alcohol and other recreational drugs can also affect vision, as can withdrawal from them. Sometimes medications can cause or contribute to visual difficulties. A surprising number of medications commonly taken by older people can have visual side-effects. They include some drugs from the following categories: cardiovascular, non steroidal anti-inflammatory, antibiotics, anti-Parkinson, and even eye medications.

Additional Visual Difficulties in Some Types of Dementia

There can also be additional visuoperceptual difficulties in dementia related to Parkinson’s disease and Lewy body dementia. In vascular dementia, if strokes occur along or near the visual pathway, a wide range of visuoperceptual difficulties, including hallucinations, can result. Importantly, changes in vision from strokes may not be noticed by an individual.

Currently, most is known about damage to the visual system in Alzheimer’s disease (and ‘posterior cortical atrophy‘, a rare variant of Alzheimer’s disease, seeFactsheet 479). The ‘plaque and tangle’ damage which characterises Alzheimer’s disease, initially accumulates in the brain areas linked to memory for processing new factual information. It lies close to a part of the visual pathway, which can also become affected from the spread of plaque and tangles. Later, other parts of the visual pathway can also be involved. Difficulties in both primary and complex visual functioning have been described for Alzheimer’s disease. (Note that some of these are similar to those described for normal ageing. However they can occur independently from, or in addition to, normal age-related visual changes and visual illness.)

Specific difficulties that have been reported in Alzheimer’s disease include:

§  reduction in number and accuracy of small eye movements

§  colour perception (loss of the blue, purple, green part of the spectrum)

§  figure-background contrast discrimination

§  depth and motion perception

§  visual acuity (but not initially)

§  object and facial recognition.

Some noticeable consequences of such problems include difficulties with:

§  assembling puzzles

§  reading books, or doing visual tasks involving close eye movements

§  watching TV shows with rapidly moving images.

Less obvious difficulties may involve the ability to:

§  play board games

§  keep handwriting in horizontal lines

§  find objects readily (even though they may be in front of a person)

§  copy images accurately

§  walk or mobilise confidently.

Dementia and Vision Problems

Evidence for the types and range of visual difficulties that can occur comes from special types of sight testing and scans, from people’s accounts of their own difficulties, and from careful observations of the visual errors repeatedly made. These include such things as:

·         difficulty re-adjusting one’s spatial orientation when moving around (even in familiar environments like walking in one’s own neighbourhood)

·         difficulty driving when rapidly changing information needs to be analysed and accurately responded to

·         difficulty judging the height of the floor when the colour flooring changes (colour illusions, figure-background and depth of field difficulties can make surfaces difficult to judge)

·         high-stepping over carpet rods or shadows, thinking they signify a change of level

·         difficulty problem solving visual illusion effects (for example, when going downstairs – determining how many steps there are, and where the next one is; going upstairs is not usually a problem)

·         resisting walking on shiny flooring because it looks wet or slippery

·         walking on the darkest patterns (or shadows) of flooring to try to avoid falling

·         misinterpreting reflections in mirrors, windows or shiny surfaces (refusal to go into a toilet because reflections make them appear to be occupied; fear of an ‘unknown person who keeps disappearing’ being present)

·         mistaking TV images for real people (‘little people’) because they are brighter and more visible than a TV console located against a dark background

·         inability to find a particular item (eg handbag, clothing) even though the item is in front of a person and appears to be in their field of vision (this can make it difficult even to locate someone’s hand to be able to return a handshake).

·         difficulty in locating people or objects because of other distracting or competing visual information (such as patterned wallpaper).

·         difficulty in positioning oneself accurately to sit down in a chair, on the bed, on the toilet (difficulty estimating depth of field, especially if the objects are behind a person, out of view; some people make multiple checks but still have difficulty and may even try to straddle them from the front. Note that such difficulty may be mistaken for incontinence)

·         inability to find objects or places because of a lack of colour contrast (for example, not seeing there is cauliflower and pasta on a white plate, or not seeing doors painted the same colour as the walls)

·         restlessness from visually over-stimulating environments (eg too many shiny Christmas decorations in some care settings that can mask important orientation cues).

As seen from the examples above, visual difficulties can affect many aspects of a person’s daily functioning. If people with dementia are living in their own home with carers who are helping them, the real extent of their visual difficulties may not be apparent until they experience a change in environment, like going out shopping, on an outing, or on holiday.

Visual difficulties and ‘perceived obstacles’ can make a person more fearful of falling, and slow down their movements while they try to walk safely. If carers and companions understand this, they can try to anticipate situations which will likely pose perceptual difficulties, help explain what is being encountered, offer their arm for support, offer encouragement, and slow down their own movements around a person with dementia.

Categories of Visual mistakes

With improved neuroscientific understanding of the visual system, it is possible to categorise different types of visual mistakes. Some examples are listed below. Although hallucinations are perhaps the best known, recent research (Jones G M M et al, 2006b) suggests they may be rarer than previously thought because other categories of visual mistakes have not previously received much attention.

Illusions – a ‘distortion of reality’ resulting from some physical property or characteristic of the image (reflection, shiny or bright surface, poor figure/background contrast, timing of presentation, etc).

Example: a person mistook the distorted reflection of a doorstop in a cylindrical, shiny, stainless steel bin, for there being a ‘mouse in the bin’.

Misperceptions – a best guess at inaccurate, degraded or distorted visual information (usually as a result of damage to the visual system). Misperceptions can be influenced by motivation, previous experience and expectation.

Example: a dark stain on the carpet was mistaken for a rat.
Example: walking down a long, dark corridor with benches along the wall resulted in a person with dementia thinking she was at a train station.

Misperceptions of illusions – what is already incorrectly seen, may be seen as even more distorted by a damaged visual system.

Example: a gentleman who approached a lift that had three large mirrors in it, mistook himself reflected three times for a crowd of people who would not move to allow him in.

Misidentifications (agnosias) – incorrectly identifying objects and people resulting from damage to specific locations of the visual cortex.

Example: a gentleman tried to use the black remote control for the TV to shave with.
Example: a mistaken thought that a large statue of a dog was real resulted in food being thrown at it daily.
Example: inability to distinguish accurately between a son, husband, and brother.

Misnaming what has been seen (or assumed to be present) – this can result from difficulties to retrieve the nouns and words to describe what is being seen accurately, or from making time perception errors and using tenses inaccurately.

Example: A collection of metal zimmer frames piled up at the end of the corridor was referred to as ‘the robots’.
Example: A lady who was severely disoriented in time thought her children were still young and living at home. She cautioned her husband as he walked past their old bedroom door, to ‘be quiet so you don’t wake the children’.

Hallucination – seeing something when there are no cues for it in the outside world. It is an internally produced visual image experienced with the eyes open. Sometimes people are aware that what is being seen is not present in the outside world, and they can stop it at will. Others may not be aware it is not real and cannot stop it at will. There are many different types of visual hallucinations.

Genuine visual hallucinations can result from urinary, chest or other type of infection, other illness, or a reaction to medication (see Factsheet 520,Hallucinations in people with dementia). They have also been more associated with Lewy body dementia, than other types of dementia. This should be considered if other causes of visual difficulties or hallucinations have been eliminated or treated, and visual hallucinations persist. (See Factsheet 403, What is dementia with Lewy bodies?)

Interventions for Visuo-perceptual Difficulties

The increased understanding of visual mistakes is generating new ideas for assisting people with dementia.

Careful attention to eye care and visual health

·         Check that any glasses worn are clean and that the prescription is correct. (For more advanced dementia, this may require use of special non-verbal tests as for people with learning difficulties.)

·         Arrange for regular eye checks.

·         Encourage the person to wear glasses if they need them. Glasses will improve acuity (sharpness) of what is being seen; however, glasses cannot correct difficulties resulting from other types of damage to the visual system.

·         If cataracts are the cause of, or contributing to, poor sight, talk to a GP about how to have them treated.

Environmental adaptations

Aiding specific visual functions can help people with dementia (Jones et al, 2008). The first thing to do is to improve lighting levels. It has been estimated that more than half of British homes do not have enough lighting even for ordinary visual purposes (Whitfield Grundy, 1992). Improved lighting has been found to be instrumental in preventing falls, and also in reducing visual hallucinations (Pankow et al, 1996).

Deliberate use of colour cues can also help significantly. For example, one study with people with advanced Alzheimer’s disease showed that changing to highly visible red cups and plates led to a 25 per cent increase in food intake and an 84 per cent increase in liquid consumption (Dunne et al, 2004). Brightly coloured toilet doors have also been used successfully in a variety of care settings to help people with dementia find the toilet independently, and more readily.

High contrast toilet seats (compared to the colour of the toilet fixtures and walls) can make it easier to locate them. If a person needs handrails choose extra-long ones so that they are as conspicuous as possible (without the person having to turn their head to look for them).

Some tips for minimizing visuo-perceptual problems

·         Provide good, even lighting (people resist going near dark areas in corridors and rooms).

·         Try to eliminate shadows.

·         Minimize busy patterns on walls and flooring.

·         Use of non-shiny, light-coloured flooring will reflect light upwards and enhance overall ambient light levels.

·         Remove or replace mirrors and shiny surfaces if they are problematic.

·         Highlight important object and visual cues (signposting/orientation points).

·         Camouflage objects that you do not want to emphasize (eg light switches or doors that people with dementia shouldn’t use).

·         Minimize ‘visual obstacles/barriers’ such as changes in floor surfaces or patterns, to assist independent walking.

·         Choose activities to match the person’s visual abilities.

Consultation went better than expected

On Friday we had a second opinion in Newcastle, and even though I left feeling drained and uncertain, I knew that someone was finally looking at my case  from a new prospective, and had decided to try to get it sorted out.

I left feeling as if i had been put through the wringer, because so many questions had been asked, and yet I hardly remembered anything about the appointment.

Then when we got home my wife sat me down, and tried to explain, what had happened, what had been said, and what had been arranged.

I then fell asleep for  over an hour, and then started asking her the questions again.

I confess that I still do not remember most of what was said, but I remember enough to feel happier, than I have been for the last year.

 I think I am driving my wife mad because I am still trying to get my head around this hospital visit.

 But I understand that I am being sent for a new scan, and some eye tests in a nuerological department, because of my vision problems

I also understand that I am having some blood tests done, which will be looked at in a neurology laboratory to see what they can find.

I admit that I was dreading this appointment, simply because I had lost total interest and faith, in the National Health Service after my last appointment at the Dementia hospital, where I had left in a total mess, and in tears.

I guess that this will all take time to get through the tests and scans, but at least I feel more positive by the fact that things are moving in the right direction. 

I understand that we can now book a holiday, and tell the insurance company that I have Mild cognitive Impairment, until we get concrete answers from the scans and tests. 

But this made a lot if sense when it was described properly by this doctor, and I think I understood what he was trying to tell me, unlike the other doctor who simply changed to diagnosis and would not discuss it further. 

Strangely enough, I felt happier leaving with the title MCI, knowing that it could possibly change at a later stage, simply because of the way the appointment was handled. 

It had been handled in a far better way and as my wife said, it was thorough, but it was handled with care and respect. 

What is even better is the fact that I have been told to ignore previous instructions,  to stop giving presentations and talks and getting involved in dementia meetings etc. 

I was told that I have been doing a good job, and should carry on until I am told otherwise. 

Time for the second opinion

On Friday morning  I have to get up very early, because I have to get a bus to travel 8 miles to Newcastle upon Tyne for my second opinion.

This is to see whether I still have Lewy a body Dementia, or whether,  it's Mild Cognitive Impairment as my new consultant has said.

I confess that I cannot understand this, as two prior consultants diagnosed me with Lewy Body Dementia, so I do not understand how things can change. 

Can these two people really be wrong.

This has been a difficult year with this dragging on, but as I was told the other day, there is no guarantee that I will get the answers on Friday.

However after the second opinion has been done,  I have to return home to travel to another hospital,  to the balance clinic, where I will see the Parkinson consultant.

So I would imagine I will be very tired by then, since this is being done in my home town 8 miles from Newcastle.

My wife has told me that the Parkinson consultant, has said that he will take things further if I do not have Lewy Body Dementia, because he is determined to find the answer to my  balance problems. 

All of this has now caused added problems, because we have nothing written down confirming what what I have, so we cannot get travel insurance.

So one way or another I hope that we get a written answer to this, so we can get away for a while.

Not enough Doctors working on Alzheimer's Research says the Alzheimer's Society

 

There are "serious gaps" in dementia research, which is slowing down the development of new treatments, a charity has said.

Few career opportunities and a lack of funding is leading to a shortage of doctors working in the field, the Alzheimer's Society warned.

Its report found that 70% of dementia PhD students leave the research area withi
n four years, while five times more people are doing a PhD in cancer than dementia.

Despite the fact that most dementia patients rely heavily on social care, fewer than 2% of the most prolific UK dementia researchers specialise in social care and social work.

The Alzheimer's Society commissioned the study from the not-for-profit research firm Rand Europe.

It found that the lack of a secure career path for researchers, due to scarce funding, was putting people off.

It also found too few mid-level positions for post-doctoral researchers to help them move to their first independent research post.

Health professionals already working in areas such as social care are also unable to secure PhD posts or junior positions.

The charity said there was a "lingering view" that not much can be done for people with dementia.

Dr Doug Brown, director of research and development at the Alzheimer's Society, said: "Dementia research is going from strength to strength in the UK but this report highlights that there are still too few people choosing it as a career, especially those from clinical and care professions.

"We must build the reputation of dementia research to show that it is one of the most cutting edgeareas of research that is poised to make significant advances in the next decade.

"By attracting and retaining more of the very best researchers in dementia, we will be able to significantly speed up progress towards innovative care and that all important cure."

Some 850,000 people in the UK have dementia, and the cost to the UK economy is put at £26.3 billion a year.

The charity Action on Smoking and Health (Ash) also published a report, endorsed by Public Health England, on the growing link between smoking and dementia.

Ash chief executive, Deborah Arnott, said: "Smokers know that smoking causes cancer and heart disease but they need to also know about the increased risk of developing dementia.

"Stopping smoking is the single most important way smokers can improve their health as well as reducing their risks of developing dementia."

Sight perception and hallucinations in Dementia

Sight, perception and hallucinations in Dementia

People with dementia may experience problems with their sight which cause them to misinterpret the world around them. In some cases, people with dementia can experience hallucinations. This factsheet considers some specific difficulties that people with dementia can have, and suggests ways to support them. Understanding potential problems and giving appropriate help, support and reassurance can greatly assist people living with dementia to feel safe, at a time when the way they perceive reality may be changing.

Vision and perception

Seeing is a complicated process that involves many different stages. Information is transmitted from your eyes to your brain where it is then interpreted, alongside information from your other senses, thoughts and memories. You then become aware of what you have seen (it is 'perceived'). Problems that involve both vision and perception can be referred to as 'visuoperceptual difficulties'. As there are many different stages involved in the seeing process, various types and combinations of mistakes can occur. Common mistakes include:

• Illusions - what the person sees is a 'distortion of reality'. This may result from a particular characteristic of the object, such as its surface being shiny or it being the same colour as the wall behind. An example might be seeing a face in a patterned curtain.
• Misperceptions - what the person sees is a 'best guess' at the inaccurate or distorted information the brain has received from the eyes. This is usually the result of damage to the visual system due to diseases such as glaucoma. For example, a shadow on the carpet could be mistaken for a hole in the floor.
• Misidentifications - damage to specific parts of the brain can lead to problems identifying objects and people. For example, distinguishing between a son, husband or brother may become difficult.

It is easy to see how these mistakes may lead to the person saying or doing things that make others think they are having delusions. However, what the person is experiencing is not a true delusion (it is not based on incorrect reasoning or 'delusional thinking') but is the result of damage to the visual system.

A visual hallucination is different from a visuoperceptual mistake. A visual hallucination involves perceiving or seeing something that is not there in the real world (see 'Hallucinations in people with dementia' below).

Causes of visuoperceptual difficulties

Normal ageing can lead to visuoperceptual difficulties, including:

• reduced sharpness (blurring)
• needing more time to adapt to changes in light levels (eg when going from a dark room into sunlight)
• the area in which objects are seen (the 'visual field') getting smaller, and loss of peripheral vision (being able to see things outside of the direct line of vision) occurring
• pupils becoming smaller
• problems with depth perception
• shadowing from small shapes floating in the visual field (known as 'floaters').

Eye conditions that can affect visuoperception include cataracts, glaucoma, macular degeneration and retinal complications from diabetes. These can all result in changes such as blurring, partial loss of visual field and, in some cases, blindness. They can also cause hallucinations and distortion in the vision - known as Charles Bonnet syndrome.

A stroke can also cause someone to have problems with their vision. They may experience central vision loss, visual field loss, eye movement problems and visual perception and processing issues.

Sometimes medications can cause or contribute to visual difficulties. They include some drugs from the following categories: cardiovascular, non-steroidal anti-inflammatory, antibiotics, drugs for Parkinson's disease, and even eye medications.

Specific types of dementia can also damage the visual system and cause visuoperceptual difficulties. These include Alzheimer's disease, Parkinson's disease dementia, dementia with Lewy bodies and vascular dementia. Rarer forms of dementia, such as posterior cortical atrophy (PCA), can also cause visuoperceptual difficulties.

Visuoperceptual difficulties in people with dementia

The specific difficulties a person experiences will depend on the type of dementia they have. This is because each type of dementia can damage the visual system in a different way.

Difficulties may include:

• decreased sensitivity to differences in contrast (including colour contrast such as black and white, and contrast between objects and background)
• reduced ability to detect movement
• changes to the visual field (how much you can see around the edge of your vision, while looking straight ahead)
• reduced ability to detect different colours (for example, a person may have problems telling the difference between blue and purple)
• changes to the reaction of the pupil to light
• problems directing or changing gaze
• problems with the recognition of objects, faces and colours
• loss of ability to name what has been seen
• double vision
• problems with depth perception.

Dementia can also result in difficulties with orientation. This in turn can lead to:

• bumping into things
• swerving to avoid door frames
• difficulties reaching for things within the visual environment (such as a cup of tea or door handle)
• getting lost or disorientated, even in familiar environments.

Some noticeable consequences of the above changes include:

• difficulties reading and writing, doing puzzles or playing board games
• problems locating people or objects, even though they may be in front of the person - this may be because of other distracting visual information (such as patterned wallpaper) or because of a lack of colour contrast (for example, not seeing mashed potato on a white plate)
• misinterpreting reflections - this may manifest as seeing an 'intruder' or refusal to go into a bathroom because reflections make it appear occupied
• mistaking images on the TV for real people
• difficulty in positioning oneself accurately to sit down in a chair or on the toilet - sometimes this difficulty is mistaken for incontinence
• appearing confused or restless owing to an environment that is visually over-stimulating and difficult to navigate.

Visuoperceptual difficulties can also lead to problems moving around. These problems can make a person fearful of falling and lead to them slowing down their movements while they try to walk safely. If carers understand this, they can try to anticipate these situations, help explain what is being encountered, offer their arm for support, offer encouragement and slow down their own movements. Specific difficulties that people with dementia may have when moving around include:

• misjudging distances and where objects are, even in familiar environments
• stepping very highly over carpet rods or shadows because the change in colour looks like a change in level
• difficulties going down stairs due to problems judging how many steps there are and where the next one is
• avoiding shiny flooring because it appears wet or slippery.

As seen from the examples above, visual difficulties can affect many aspects of a person's daily functioning. If people with dementia are living in their own home with carers who are helping them, the real extent of their visual difficulties may not be apparent until they experience a change in environment, such as going out shopping, on an outing, or on holiday.

How to support someone with visuoperceptual difficulties

This section looks at ways to reduce visuoperceptual difficulties and to support a person experiencing these problems.

Careful attention to eye care and visual health

• Arrange for regular eye checks, and inform the optometrist of the dementia so that this can be taken into consideration when arranging treatment and appointments.
• If the person wears glasses, check that they are clean and that the prescription is correct, and encourage the person to wear them.
• Check the person is wearing the correct glasses for the correct distance, eg reading or television.
• Research has shown that multifocal glasses can increase the risk of falls in people when they are outside the home. It may be useful to have separate distance and reading glasses. Although you will need to check that the correct glasses are being worn and have them clearly labelled.
• If cataracts are the cause of, or are contributing to, poor sight, talk to an optometrist about how to have them treated.

Environmental adaptations

An occupational therapist can visit the home to assess whether any equipment or adaptations are needed. This is called an occupational therapy home assessment. The occupational therapist can arrange minor adaptations, such as handrails, adapted cutlery and special chairs, through social services. For more information, see factsheet 429, Equipment, adaptation and improvements to the home.

Tips:

• Deliberate use of colours can help significantly. For example, a red plate on a white tablecloth is more easily visible than a white plate, and toilet seats are easier to see if they contrast with the colour of the toilet bowl and walls. Colour can also be used to highlight important objects and orientation points (eg the toilet door) and to camouflage objects that you do not want to emphasise (eg light switches or doors that the person doesn't need to use).
• Improve lighting levels around the home. This can reduce visual difficulties and help to prevent falls. Lighting should be even around the home and should minimise shadows - some people resist going near dark areas in corridors and rooms.
• Minimise busy patterns on walls and flooring and try to reduce any changes in floor patterns or surfaces - the person may see such changes as an obstacle or barrier.
• Remove or replace mirrors and shiny surfaces if they cause problems.
• Close curtains or blinds at night.

Practical tips

If a person fails to recognise an object or person, try not to draw any unnecessary attention to the mistake and avoid asking questions that might make them feel 'put on the spot'.

If appropriate, give the object to the person and explain how it is used. If they do not accept this explanation, try not to argue with them. Ignore the mistake and listen to what they are trying to say. Being corrected can undermine a person's confidence and they may become reluctant to join in conversation or activities. For this reason, it is important to focus on the emotions behind what is being said, rather than the facts or details.

If the person struggles to recognise people, ask friends and relatives to introduce themselves to the person. If the person doesn't recognise somebody it can be distressing for them and can also be upsetting for those around them. If this happens, try to reassure the person and find tactful ways to give them reminders or explanations.

Try to make activities accessible for the person. For example, if the person enjoyed reading but is no longer able to do so, consider reading to the person or using audiobooks. Likewise, if the person is unable to read the newspaper or watch TV, radio programmes can help people keep up with current affairs. Cooking can be an enjoyable activity if it is made easy - for example using pre-chopped vegetables and ready-made sauces.

Hallucinations in people with dementia

What are hallucinations?

A hallucination is an experience of something that is not really there. Hallucinations can occur for all the senses, though visual hallucinations (seeing things that are not really there) are the most common type of hallucination experienced by people with dementia.

Visual hallucinations can be as simple as seeing flashing lights, or as complex as seeing animals, people or bizarre situations. Less often in people with dementia, hallucinations can involve hearing (voices, for example), smelling, tasting or feeling things that are not really there.

Hallucinations and dementia

People with dementia are often thought to be hallucinating when in fact they are making a mistake about what they have seen (see 'Visuoperceptual mistakes' above). There are some specific forms of dementia, however, where hallucinations are more common. These include dementia with Lewy bodies and Parkinson's disease dementia. Hallucinations can also occur in Alzheimer's disease.

Hallucinations in people with dementia with Lewy bodies usually take the form of brightly coloured people or animals. They often last for several minutes and can occur on a daily basis. Around one in 10 people with dementia with Lewy bodies also experience smells that are not really there (known as olfactory hallucinations). People with dementia may also experience auditory hallucinations (hearing sounds or voices) and tactile hallucinations (sensing things that aren't there).

Supporting the person

If you suspect that a person is hallucinating, try to explain calmly to them what is happening. If they cannot retain this information, repeat it when they are calmer. However, if this is still not possible, there is little point in arguing. Attempting to convince someone that they are mistaken can lead to more distress, for both parties.

Try to stay with the person and offer reassurance. Tell them that what they are sensing is not evident to you, but you want to know what they are experiencing. Listen carefully to what they describe. Could it be that language difficulties can explain what they are reporting? For example, someone might refer to green cushions as 'cabbages'.

Try distracting the person to see if this stops the hallucination. For visual hallucinations, the environmental adaptations listed above - including improving lighting levels and eliminating shadows - are also important to consider, as are the points listed under 'Careful attention to eye care and visual health'. For auditory hallucinations, check the person's hearing and make sure that their hearing aid is working, if they have one. People are less likely to hear voices that are not there when they are talking to someone real, so company can also help.

Treatment

It is important to note that hallucinations can be caused by the side-effects of medication (including some antidepressants and drugs for Parkinson's disease) or certain illnesses (including fever, seizure, stroke, migraine and infection). If a person is experiencing hallucinations you should consult their GP. If the person's hallucinations involve multiple senses, seek medical help immediately, as this can indicate serious illness. It is also a good idea to seek medical attention if the hallucinations frighten the person, last a long time or occur often.

When visiting the GP, it will help if you bring notes about:

• what the person saw or sensed
• what time of day it occurred and after what event (eg nap, meal, exercise)
• where it happened and how long it lasted
• how the person responded (eg, if they were distressed) and the words they used to describe what they experienced
• medication the person is taking and the dosage (including any supplements and over-the-counter medications)
• the person's medical history, including any previous sight (or other sensory) conditions and mental health issues
• the person's use of alcohol or other recreational drugs.

Some people with dementia experiencing hallucinations respond to anti-dementia drugs, particularly people with dementia with Lewy bodies. In some situations, people with dementia may be prescribed antipsychotic medication. Antipsychotic drugs do help some people with dementia, but they can also cause side-effects and should be used with caution and be reviewed regularly. However, there are certain circumstances where antipsychotic medication can be effectively used to treat hallucinations, despite their risks. In some cases they can eliminate or reduce the intensity of psychotic symptoms, such as delusions and hallucinations, and have a calming and sedative effect. For more information, see factsheet 408, Drugs used to relieve behavioural and psychological symptoms in dementia.

If a person with dementia with Lewy bodies must be prescribed an antipsychotic drug, it should be done so under constant supervision and reviewed regularly. This is because people with dementia with Lewy bodies are at particular risk of severe adverse reactions to antipsychotic medication. If you have questions about the use of antipsychotic drugs speak to the doctor.

For details of Alzheimer's Society services in your area, visit alzheimers.org.uk/localinfo

For information about a wide range of dementia-related topics, visitalzheimers.org.uk/factsheets

Useful organisations

Macular Society

A national charity offering support and advice for anyone affected by central vision loss.

PO Box 1870
Andover SP10 9AD

T (Helpline) 0300 3030 111
E help@macularsociety.org
W www.macularsociety.org

Royal National Institute of Blind People

A charity that offers support and advice to blind and partially sighted people in the UK.

105 Judd Street
London WC1H 9NE

T 0303 123 9999
E helpline@rnib.org.uk
W www.rnib.org.uk

Dementia and Sight Loss Interest Group

The Dementia and Sight Loss Interest Group was set up in 2008 as part of Vision 2020 UK, to develop and promote better understanding of the issues facing people affected by dementia and sight loss. It also develops and disseminates materials, resources and tools that contribute to good practice.

The group consists of Alzheimer's Society, ARUP, Macular Society, RNIB and Thomas Pocklington Trust.

Factsheet 527

Last reviewed: October 2012
Next review due: October 2015

Reviewed by: Dr Andrea Tales, Senior Lecturer, Department of Psychology, Swansea University; Dr Jo Jefferis, NIHR Research Fellow, Institute of Neuroscience, Newcastle University; and Dr John-Paul Taylor, Wellcome Intermediate Clinical Fellow and Honorary Consultant in Old Age Psychiatry, Institute for Ageing and Health, Newcastle University

This factsheet has also been reviewed by people affected by dementia. A list of sources is available on request.