As a leading cause of dementia around the globe, Alzheimer's disease attracts billions of dollars in research funding in the hope of finding either a cure or pathways to prevention.

It's not easy going. All but a mere 1 percent of studies show promise, with life-changing treatments still on the horizon. But there is still reason to keep up hope.

What is Alzheimer's disease?

Alzheimer's disease is a chronic neurological condition characterised by worsening short term memory loss. Symptoms progress over time as the condition deteriorates to include challenges in finding the right words, disorientation, loss of social skills, and emotional changes.

Roughly 30 percent of people over the age of 85 are affected by the disease, making it a critical issue as improvements in healthcare see a rise in the average age of the world's population.

The disease is itself rarely fatal, often because those in progressed stages of Alzheimer's are at a greater risk of developing serious infections and other life-threatening complications.

What causes Alzheimer's disease?

The condition is caused by the steady loss of neurons, typically beginning in the wrinkled outer layer known as the cortex before affecting structures deeper inside the brain.

Ongoing research continues to provide details on this degeneration, with most explanations pointing at a build-up of proteins called beta-amyloid. Changes in the structure of another protein - called tau - might also be responsible. Together, these altered proteins seem to affect how neurons communicate and function, eventually leading to the cell's death.

Many cases of Alzheimer's disease appear to be heavily influenced by various genes, though it is clearly a complicated condition affected by both inherited and environmental factors.

Treatments based on increasing levels of a key neurotransmitter have been found to provide temporary improvement, but as of yet there is no way to prevent or reverse degeneration.