A study that imaged spontaneous CA1 pyramidal neuron activity in anesthetized amyloid precursor protein (APP)/presenilin-1 (PS1) transgenic AD model mice observed increased fractions of silent and hyperactive neurons near amyloid-β (Aβ) plaques stained with thioflavin-S in 6–7-month-old mice.85 Here, PSEN1 is linked to Alzheimer disease.