Scientists believe they have found a key which could help lead to an earlier diagnosis of neurological disorders such as Alzheimer's and Parkinson's.
Scientists at Cambridge University's Department of Chemistry have attempted to map the pathway which creates the "aberrant" proteins at the root of such conditions.
A file image showing a cross section of a normal brain (right) and one of a brain damaged by advanced Alzheimer's disease
They hope it could be a much-needed breakthrough to help introduce a new generation of drugs to target the disorders.
The research, published in the Proceedings of the National Academy of Sciences journal, could prove useful in the work to try and combat the dementia-related diseases which increasingly affect ageing populations, the scientists claim.
Degenerative diseases such as Alzheimer's are triggered when the normal structures of protein molecules within cells become corrupted.
The research was established by Cambridge Professor Christopher Dobson who realised over 15 years ago that the "misfolding" of proteins should be investigated.
Dr Tuomas Knowles, lead author of the study, said: "There are no disease modifying therapies for Alzheimer's and dementia at the moment, only limited treatment for symptoms.
"We have to solve what happens at the molecular level before we can progress and have real impact.
"We've now established the pathway that shows how the toxic species that cause cell death - the oligomers - are formed.
"This is the key pathway to detect, target and intervene - the molecular catalyst that underlies the pathology."
The new research looked at how oligomers, which can lead to Alzheimer's disease, are formed.
The oligomers are small enough to spread easily around the brain - killing neurons.
It was found that once a small but critical level of malfunctioning protein 'clumps' have formed, a runaway chain reaction is triggered which multiplies the number of these protein composites.
The scientists found that this process creates a batch of clusters which initially contain a few protein molecules.
The researchers note: "Small and highly diffusible, these are the 'toxic oligomers' that careen dangerously around the brain cells, killing neurons and ultimately causing loss of memory and other symptoms of dementia."
Dr Knowles claimed that years spent developing research techniques are beginning to pay off as the research team is starting to solve "some of the key mysteries" of these neurodegenerative diseases.