FIGURE 4.

Type 2 oligomers reach confluence when the Thioflavin S plaque load is ≈ 0.5% to 4%. The Thioflavin S (ThioS) core (red) contains densely packed amyloid fibrils. The toxic halo (brown) contains Type 2 oligomers and extends ≈ 50 microns from the edge of the ThioS core. ³⁴ The radius of ThioS cores (r) ranges from ≈ 10 to 25 microns. The ratio of R/r ranges from ≈ 3 to 6. When the ThioS plaque load equals r³/R³, the toxic halos in the brain become confluent. This occurs when the ThioS plaque load is 1/6³ to 1/3³ = ≈ 0.5 to 4%. In humans with Alzheimer's disease, the ThioS plaque load ranges from ≈ 0.1% to 0.4% ³⁷