Very recently, we reported the interaction of Aβ and tau synaptotoxicity, with relatively low volumes of certain Alzheimer’s disease brain extracts inhibiting LTP in a manner that requires the presence of both Aβ and tau.35 Whether or not this interaction affects LTD facilitation by Aβ and tau in Alzheimer’s disease brain extracts remains to be determined. This evidence concerns the gene MAPT and early-onset autosomal dominant Alzheimer disease.