Dementia patients often experience a merging of the present and past, meaning that different times of their life are no longer clearly separable, one expert has said.
The confused timeline of their life can result in an inability to recognise loved ones, stated Rosemarie Drenhaus-Wagner of a Berlin-based initiative for relatives of people with Alzheimer's disease.
Such situations can result in immense sadness for family members, she added, and dementia patients might mistaken their grandchildren for their own children.
Commenting on how people living with dementia respond to those around them, Ms Drenhaus-Wagner said: "They orientate themselves based on behaviour.
"When loved ones take on care-giving tasks, then they are perceived as the care-givers or nurses."
A study released last week suggests that dementia will be costing the UK economy £50 billion per year within the next 30 years.
The 'Developing our brains from Cradle to Grave' report, commissioned by government think-tank Foresight, predicts there could be 9.5 million people in the UK aged over 80 by the year 2071.
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