The scientists conducted regular PET scans and memory tests on a 56-year old Alzheimer’s patient, and after the patient died, pathological and neurochemical analyses of the brain tissue were conducted.

The combined analyses provided a detail picture of how Alzheimer’s disease develops.

The results revealed that high concentrations of amyloid plaques were identified at an early stage of the disease when the patient experienced slight memory loss.

The levels remained unchanged as the disease progressed, while there was an increasingly declining energy metabolism in the brain.

In addition, greater accumulation of plaque was accompanied by a reduction in the number of neuronal nicotinic receptors in the brain, which are central to memory function.

Study researcher Nordberg said the study shows that new, modern imaging technology known as molecular imaging makes it possible to discover the disease at an early stage.

"This opens up new opportunities for early diagnosis and for understanding the causes of the disease and identifying patients who can be expected to respond well to future Alzheimer’s therapy," Nordberg said.