Table 1.

Characterization of the two subpopulations of Aβ.

Toxic Subpopulation	Non-Toxic Subpopulation
Mw > 50 kDa (HMW, high mol. weight)	Mw < 50kDa (LMW, low mol. weight)
unrelated to plaques	related to plaques
no reaction with anti fAβ antibody	binding anti-fAβ antibody
“type 1” AβO: toxic	“type 2” AβO: non-toxic
disrupt memory function	no effect on memory function

AβO: Aβ oligomer, fAβ: fibrillar β-amyloid.