Dementia causes changes in the brain that may cause someone to hallucinate – see, hear, feel, or taste something that isn’t there. Their brain is distorting or misinterpreting the senses. And even if it’s not real, the hallucination is very real to the person experiencing it.
Dementia is the most common cause of visual hallucinations in older adults,10 and they can occur with dementia of any etiology. The most common cause of dementia is Alzheimer’s disease, and approximately 18% of patients with Alzheimer’s disease experience visual hallucinations.
Hallucinations are caused by changes in the brain which, if they occur at all, usually happen in the middle or later stages of the dementia journey. Hallucinations are more common in dementia with Lewy bodies and Parkinson’s dementia but they can also occur in Alzheimer’s and other types of dementia.
Hallucinations, though common in youth and younger adults, are not the preserve of these age groups. Accumulating evidence shows that hallucinatory experiences are also present at surprisingly high rates in healthy older adults in the general community.
The mind often plays tricks on people with dementia as brain cells degenerate. Their brains often distort their senses to make them think they are seeing, hearing, feeling, smelling or experiencing something that isn’t really there.
Symptoms of dehydration can include headaches, lethargy and hallucinations. In extreme cases, dehydration may result in death.
Common Causes of Hallucinations
There are many causes of hallucinations, including: Being drunk or high, or coming down from such drugs like marijuana, LSD, cocaine (including crack), PCP, amphetamines, heroin, ketamine, and alcohol. Delirium or dementia (visual hallucinations are most common)
What Are the Seven Stages of Dementia?
Experts suggest that signs of the final stage of Alzheimer’s disease include some of the following: Being unable to move around on one’s own. Being unable to speak or make oneself understood. Needing help with most, if not all, daily activities, such as eating and self-care. 5
Dementia may cause a person to have hallucinations. This is most common in people living with dementia with Lewy bodies, although other types of dementia may also cause hallucinations.
A stroke can sometimes lead to hallucinations or delusions. Hallucinations and delusions are also known as ‘psychotic symptoms’. This can be due to mental health problems, but it can also be caused by a stroke. It may happen in up to one in 20 people after a stroke.
Change in mental status or sudden behavior change, such as confusion, delirium, lethargy, hallucinations and delusions. Chest pain, tightness or pressure, or rapid heart rate.
Remain calm, and try to help the person:
In the earlier stages, memory loss and confusion may be mild. The person with dementia may be aware of — and frustrated by — the changes taking place, such as difficulty recalling recent events, making decisions or processing what was said by others. In the later stages, memory loss becomes far more severe.
It can be helpful to think of dementia progressing in three stages – early, middle and late. These are sometimes called mild, moderate and severe, because this describes how much the symptoms affect a person.