Studying individual synaptosomes and co-localising the AT8 + tau signal with T181-positive tau at the single-aggregate level, as well as determining the presence of exposed phosphatidylserine (“eat me” signal), CD47 (“don’t eat me” signal), and synaptogyrin-3 in synaptosomes containing AT8 + tau (see Supplemental Figs. 7 and 8 for representative images), we were able to explore how synaptic tau aggregation alters synaptic function and pruning, which are potentially contributing to cognitive deficits in AD. Here, MAPT is linked to Cognitive impairment.