Skip to main content
. Author manuscript; available in PMC: 2017 May 18.
Published in final edited form as: Neuron. 2016 May 5;90(4):740–751. doi: 10.1016/j.neuron.2016.04.009

Figure 6. SWR and SWR-associated slow gamma characteristics in young apoE3-KI and apoE4-KI mice are differentially affected by aging.

Figure 6

(A) SWR abundance in 4–5-month-old apoE3-KI and apoE4-KI mice at 3, 4, 5, and 6 SD thresholds. (unpaired t tests; t(14) = 3.129, 3.126, 2.939, and 2.634, respectively).

(B) Percent power spectra during SWRs. Frequency of peak ripple power is significantly lower in young apoE4-KI mice than in young apoE3-KI mice; 156.0 ± 1.562 Hz vs 175.1 ± 1.98 Hz, (unpaired t test, P < 0.0001; t(14) = 7.252).

(C) Quantification of average SWR length in young apoE3-KI and young apoE4-KI mice (unpaired t-test, t(14) = 3.431)

(D) Quantification of SWR-associated slow gamma power (z-scored) in hippocampal subregions (unpaired t test; t(14) = 3.281 for CA1-sr).

(E) Distribution of SWR-associated slow gamma power (z-scored) in CA1-sr. Inset: Recalculation of average SWR-associated slow gamma power excluding events with z-scored slow gamma power > 7 (dashed line).

(F) Distribution of SWR-associated slow gamma power (z-scored) in CA1-sr for all genotype and age groups.

(G) SWR-associated slow gamma power in CA1 stratum radiatum recalculated after exclusion of events with z-scored slow gamma power > 7 (dashed line in panel F). Two-way ANOVA with corrected post-hoc tests shows significant effects of genotype (P < 0.0001, F(1,39) = 23.00) and age (P = 0.0388, F(1,39) =4.571) and significant interaction between the two (P = 0.0263, F(1,39) = 5.332).

(H) Fraction of SWRs with suppressed CA1 stratum radiatum slow gamma activity below baseline (z-score power < 0) for all genotype and age groups. Two way ANOVA with corrected post-hoc tests shows significant effects of genotype (P < 0.0001, F(1,39) = 32.84) and age (P = 0.0013, F(1,39) = 11.92) and significant interaction between the two (P = 0.0033, F(1,39) = 9.823).

*P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001. n = 9 and 7 for young apoE3-KI and apoE4-KI, respectively; n = 14 and 13 for aged apoE3-KI and apoE4-KI, respectively. Error bars and shading indicate SEM. See also Figure S6.