Symptoms, including biochemical correlates, of age-related memory loss (ARML) in a mammal are beneficially affected by administering to the mammal small doses of bodies, such as liposomes, of a size resembling that of mammalian cells, the bodies having phosphate glycerol head groups presented exteriorly on their surfaces. Preferred are liposomes comprised of 50-100% phosphatidylglycerol, with the phosphoglycerol headgroups thereof exteriorly presented.