PSEN1 and Alzheimer disease: Surprisingly, puncta density increased by ∼20% at apical dendrites in APP/PS1, a significant difference (WT 5.13 ± 0.22 vs. AD 6.20 ± 0.22 puncta/μm, p = 9.8 × 10−4; Figures 3E–3H), and basal dendrites showed no change (WT 4.23 ± 0.17 vs. AD 4.54 ± 0.25 puncta/μm, p = 0.302; Figure 3I–3L).