Fig. 5

Schematic diagram of T2 distribution profiles in ageing and Alzheimer’s disease. Midpoint values for each hypothetical distribution are represented by orange bars and ‘μ’ markers on each x-axis. Green and red arrows represent factors that increase or decrease T2, respectively. The number of arrows represents the relative dominance of each effect. In summary, the model suggests that factors that increase T2 are present in both healthy ageing and Alzheimer’s pathology; however, factors that decrease T2 are more dominant in Alzheimer’s disease. Early Alzheimer’s disease pathology is characterised by an increase the distribution without an increase in the midpoint