The early signs of dementia are very subtle and may not be immediately obvious.
Early symptoms also vary a great deal.
Usually though, people first seem to notice that there is a problem with memory, particularly in remembering recent events.
Memory loss that affects day-to-day function
It's normal to occasionally forget appointments or a friend's phone number and remember them later.
A person with dementia may forget things more often and not remember them at all.
Difficulty performing familiar tasks
People can get distracted from time to time and they may forget to serve part of a meal.
A person with dementia may have trouble with all steps involved in preparing a meal.
Confusion about time and place
It's normal to forget the day of the week - for a moment.
But a person with dementia may have difficulty finding their way to a familiar place, or feel confused about where they are.
Problems with language
Everyone has trouble finding the right word sometimes, but a person with dementia may forget simple words or substitute inappropriate words, making sentences difficult to understand.
Problems with abstract thinking
Balancing a cheque-book can be difficult for anyone, but a person with dementia may have trouble knowing what the numbers mean.
Poor or decreased judgment
A person with dementia may have difficulty judging distance or direction when driving a car.
Problems misplacing things
Anyone can temporarily misplace a wallet or keys. A person with dementia may put things in inappropriate places.
Changes in personality or behaviour
Everyone becomes sad or moody from time to time. Someone with dementia can exhibit rapid mood swings for no apparent reason. They can become confused, suspicious or withdrawn.
A loss of initiative
It's normal to tire of some activities. But dementia may cause a person to lose interest in previously enjoyed activities.
Only a medical practitioner such as your local doctor or specialist can diagnose dementia.
If a firm diagnosis has been made, it is helpful to find out about dementia and the support that is available to help you manage.
Call the National Dementia Helpline on 1800 100 500.