Q As people age, is dementia unavoidable? So what actually causes it apart from degenerating cells and old age? What can we do to prevent it?

A Dementia refers to a group of disorders of the brain arising from different causes. They all have in common an irreversible progressive decline in intellectual function, especially memory or IQ.

Some of the symptoms include forgetfulness or not being able to solve mathematical questions or puzzles that the person was previously able to do.

Dementia affects mostly older people aged 65 and above, and its risk increases with age. The risk factors include diabetes and high blood pressure conditions.

Historically, it was thought that people were born with a fixed number of brain cells and the connections between them, once established during development, could not be regenerated.

But now, there is evidence showing that the brain remains plastic throughout life and it can form new connections, even for those with dementia.

Exercise, social interaction and mentally stimulating activities may encourage such connections to form.

The benefits of such exercises extend beyond the brain to the whole person as they meet the human need for engagement and having a sense of purpose, meaning and pleasure in life.

They also reduce the feelings of loss and helplessness that often accompany dementia.

While some medication has been shown to be able to retard the progression of the disease, the diseased brain is still trainable with mentally stimulating activities.

• Dr Ng Chong Jin, Associate Consultant, Department of Geriatric Medicine, Khoo Teck Puat Hospital
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