Dementia refers to the decline in brain functioning which affects one's ability to function like they did before. There are many causes of dementia of which Alzheimer's disease is the commonest cause. Determining the underlying cause of an individual's dementia is important as it helps us better predict the change over time and thus the treatment and support required.
Memories laid down earlier in life tend to be more robust. One way to explain it is that those memories have been better indexed as one would have reviewed it several times over the years when brain functioning was normal. When brain performance declines, new memories do not get indexed as well and therefore do not get stored as well as they did before.
It is sometimes difficult to appreciate the decline in one's own memory. This is because your long term memory may still be good and you are not aware of the decline in your short term memory. When a person has problems with their 'short term memory', they tend to forget that they have forgotten and will not appreciate the severity of their memory impairment. It is more likely that those close to them would notice this change and the extent of it to a greater degree than the individual themselves.
This issue is complex and is usually a combination of various factors. Having to repeat yourself, providing care and support 24/7 without seeing any improvements, not understanding what is going on, not being able to get some rest and feeling guilty for getting impatient at your loved ones are some of the reasons for the frustration and anger felt by carers.
There are many explanations for this. It may relate to impaired attention which is often an early feature of dementia. In later stages it may relate to the inability to recall the correct place for the item or misidentifying the purpose and function of the item they are trying to put away. Sometimes people with dementia hide money (or put it in a 'safe place') as they mistakenly think someone has taken it when they are unable to remember where they put it last or how much they had in the first place. This belief can sometimes become so strong that they become convinced that someone specific has taken them. This will require careful consideration and thorough investigation as although this may be a treatable delusion, in some cases, the latter may actually be happening.
Individuals with dementia can find it difficult to appreciate the changes in their behaviour and like anyone else they treasure their freedom and liberty. The carer is usually the first to notice these changes and naturally tries to modify the behaviour of the person with dementia by correcting them. This can cause conflicts. As the person with dementia may not remember the incident or the conversation they had, they are unable to modify their behaviour. A carer who does not understand the nature of dementia may repeatedly continue trying to correct the behaviour of the person affected which can result in the carer becoming frustrated and the person with dementia angry. Personality changes and loss of social etiquette can occur in dementia depending on the areas of the brain affected.
When short term memory becomes significantly impaired it is difficult for a person to retain what they have recently been told. They may also forget that they have asked that same question already. Therefore a person with dementia may ask the same questions again but genuinely believe that it is the first time they are asking that question. It is therefore important for carers not to irritate or demean the individual with dementia with replies like 'I have told you already' or by raising your voice in frustration. This can be upsetting for a person who is forgetful. We would feel the same if we got that response whenever we asked someone a question for the first time.
The functioning of a person's brain is compromised in dementia. The inflammation caused by the infection affects their brain function to a greater extent than someone without dementia. The change can be rapid and noticeable, within hours to days. It is very important to contact your GP if this occurs as the cause of the infection needs to be identified and treated as soon as possible. A urine infection is often the underlying cause and can be easily treated with the right antibiotics.