custom-developed matlab software  (MathWorks Inc)

Journal: iScience

Article Title: Sleep-dependent decorrelation of hippocampal spatial representations

doi: 10.1016/j.isci.2024.110076

Figure Lengend Snippet: Hippocampal neuronal activity represents object exploration during OPR task (A) Normalized firing rate of hippocampal single-units in relation to object exploration in the sample phase of the OPR task. Units increasing their firing rate over 2 SD for at least 200 ms from object exploration onset (time 0) were classified as activated neurons (object cells, n = 114). The remaining non-encoding neuronal population did not significantly change its firing rate in relation to object exploration ( n = 136). (B) Average pairwise crosscorrelograms between object cells (red, n = 353 pairs) and non-encoding neurons (black, n = 812 pairs). Synchrony between object cells was significantly larger ( p < 8.5 × 10e-10, Wilcoxon rank-sum test). Average peri-event crosscorrelograms between hippocampal units and sleep oscillations showing consistent differences between object cells and non-encoding cells: slow wave activity (C, p < 6.1 × 10e-4), spindles (D, p < 6.4 × 10e-3) and ripples (E, p < 1.6 × 10e-3). Wilcoxon rank-sum test.

Article Snippet: Scoring was performed by quantifying the exploration time of each object using custom-developed software in MATLAB.

Techniques: Activity Assay

Journal: iScience

Article Title: Sleep-dependent decorrelation of hippocampal spatial representations

doi: 10.1016/j.isci.2024.110076

Figure Lengend Snippet: Place cells are more excitable and synchronized than non-spatial neurons during sleep (A and B) Example place cell (A) and non-spatial cell (B) simultaneously recorded in the same experimental session, during the test phase (rat GV11, session 03). Left, spatial trajectory (black) and single spikes (red) discharged during arena exploration. Large white circles depict object location. Right, heat maps. (C) Average firing rates of place cells (PC, n = 192) and non-spatial cells (NS, n = 324) according to task phase. Note place cells are consistently more active than non-spatial cells (two-way ANOVA, p = 3.7 × 10e-21). Task stages were also different within groups (Kruskal-Wallis test, p = 4.9 × 10e-9 for place cells and p = 1.4 × 10e-6 for non-spatial cells). (D) Average firing rates of place cells and non-spatial cells according to sleep phase. Note place cells are consistently more active than non-spatial cells (two-way ANOVA, p = 3.1 × 10e-10). Sleep phases were also different within groups (Wilcoxon signed rank test, p = 1.37 × 10e-10 for place cells and p = 6.6 × 10e-8 for non-spatial cells). (E) Peak pairwise crosscorrelogram amplitude for place cells and non-spatial cells according to task phase. Note place cells are consistently more synchronized than non-spatial cells, particularly during sleep (Kruskal-Wallis test, p = 4.8 × 10e-26 for place cells and p = 0.20 for non-spatial cells). (F) Peak pairwise crosscorrelogram amplitude for place cells and non-spatial cells according to sleep phase. Note place cells are consistently more synchronized than non-spatial cells (two-way ANOVA, p = 1.8 × 10e-167), particularly during NREM. Sleep phases were also different within groups (Wilcoxon rank-sum test, p = 7.9 × 10e-26 for place cells and p = 4.5 × 10e-33 for non-spatial cells). (G) Average pairwise crosscorrelograms between place cells (red, n = 1,503 pairs) and non-spatial neurons (black, n = 4,221 pairs). Synchrony between place cells was significantly larger (Wilcoxon rank-sum test, p = 3.8 × 10e-89). Average peri-event crosscorrelogram between hippocampal units and sleep oscillations showing consistent differences between place cells and non-spatial cells: slow wave activity (H, p = 2.3 × 10e-7), spindles (I, p = 1.6 × 10e-7), and ripples (J, p = 4.1 × 10e-8). Wilcoxon rank-sum test. Asterisks indicate significant differences, p < 0.05, pairwise Tukey’s test. See also Figures S9 and .

Article Snippet: Scoring was performed by quantifying the exploration time of each object using custom-developed software in MATLAB.

Techniques: Activity Assay

Journal: iScience

Article Title: Sleep-dependent decorrelation of hippocampal spatial representations

doi: 10.1016/j.isci.2024.110076

Figure Lengend Snippet: Stability of spatial representations decreases across sleep Examples of place cells recorded in the exploration phases of the OPR task (A) or the open field (C). Average spatial correlation of place cells in relation to NREM duration for the OPR task (B, computed between test and sample phases, r = −0.53, p = 0.03, Spearman’s correlation) or the open field (D, computed between after and before sleep, r = 0.07, p = 0.97, Spearman’s correlation). Examples of population vector correlation maps obtained from sessions with different NREM durations for the OPR task (E, n = 15 sessions) and the open field (G, n = 9 sessions). Population vector correlation (stability index) in relation to NREM duration for the OPR task (F, r = −0.55, p = 0.028, Spearman’s correlation) and open field (H, r = 0.35, p = 0.36, Spearman’s correlation). Only significant linear regressions are plotted.

Article Snippet: Scoring was performed by quantifying the exploration time of each object using custom-developed software in MATLAB.

Techniques: Plasmid Preparation