Fig 1.
Trace and delayed conditioning.
(A) Schematic illustration of trace conditioning and delayed conditioning. (B) A graph showing the percentage of freezing over time during trace conditioning. (n = 12). Open circles represent the percentage of freezing during the CS presentation, while filled circles represent the percentage of freezing during the trace interval. (C) A bar graph comparing the averaged percentage of freezing during the baseline period and the retrieval period, divided into the CS presentation period and the trace interval. During both the baseline and retrieval periods, the CS was presented five times. Statistical comparisons using Multiple Mann–Whitney tests followed by the Holm–Sidak method show significant differences: for CS presentation, * p = 0.025125; for trace intervals, **p = 0.002557. Error bars represent s.e.m. (D) A graph showing the percentage of freezing over time during delayed conditioning (n = 17). Filled circles represent the percentage of freezing during the CS presentation, while open circles represent the percentage of freezing during the hypothetical trace interval. (E) A bar graph comparing the averaged percentage of freezing during the baseline period and the retrieval period, divided into the CS presentation period and the hypothetical trace interval. During both the baseline and retrieval periods, the CS was presented five times. Statistical comparisons using Multiple Mann–Whitney tests followed by the Holm–Sidak method show significant differences: for CS presentation, ****p < 0.0001; for hypothetical trace intervals, ***p = 0.000768. Error bars represent s.e.m.
Fig 2.
Clustering of claustral neurons based on behavioral epochs.
(A) Distribution of clustered neurons (n = 173) in t-SNE space (top left). A schematic illustrating the process of subgroup division (bottom). Percentage of three clusters in the trace conditioning retrieval or delayed conditioning retrieval group (bottom right). The recorded number of cells per animal was 5.96 ± 4.4 units. Filled circles represent non-exploratory neurons, while open circles represent exploratory neurons. (B) Z scored firing rates of neurons within each cluster. C1 (top, n = 44), C2 (middle, n = 71), and C3 (bottom, n = 58). (C) Schematic representation of exploratory behavior. (D) An exemplary exploratory neuron shows an increase in firing rate during exploratory behavior. The periods of exploratory behavior are indicated by cyan shading. (E) This graph shows the total time (left) and total count (right) of exploratory behavior measured during the baseline period before CS presentation. Error bars indicate the standard error of the mean (s.e.m.).
Fig 3.
Non-Exploratory neurons in Cluster 1 during the retrieval phases of trace conditioning.
(A) Representative Z score example of a non-exploratory neuron from the trace conditioning retrieval group in cluster 1, with example neuronal spike traces and cue presentation periods indicated by dashed lines. (B) The mean Z score values of non-exploratory neurons in cluster 1 of the trace conditioning retrieval group (n = 14) were found to change as the behavioral sessions progressed (**p = 0.0034; Friedman test followed by FDR by Benjamini and Hochberg, Q < 0.05 are marked with a star). (C) Comparison of average z-scores between trace intervals where freezing was observed and those where it was not (n = 23, 12 respectively; p = 0.5716 via Mann–Whitney tests). (D) Correlation between percent freezing and mean Z-scores during trace intervals where freezing was observed. Significant correlation was observed (n = 23; Spearman correlation r = 0.4983, * p = 0.0155). (E) Correlation between head velocity and mean Z-scores during trace intervals where freezing was not observed (n = 12; Spearman correlation r = -0.2517, p = 0.4303). Solid lines and shades indicate linear regression and its 95% confidence intervals, respectively, for (D), (E).
Fig 4.
Non-exploratory neurons in Cluster 1 during the retrieval phases of delayed conditioning.
(A) Representative Z score example of a non-exploratory neuron from the delayed conditioning retrieval group in cluster 1, with example neuronal spike traces and cue presentation periods indicated by dashed lines. (B) The mean Z score values of non-exploratory neurons in cluster 1 of the delayed conditioning retrieval group (n = 17) were found to change as the behavioral sessions progressed (****p < 0.0001; Friedman test followed by FDR by Benjamini and Hochberg, Q < 0.05 are marked with a star). (C) Comparison of average z-scores between trace intervals where freezing was observed and those where it was not (n = 40, 10 respectively; p = 0.5617 via Mann–Whitney tests). (D) Correlation between percent freezing and mean Z-scores during trace intervals where freezing was observed. Significant correlation was not observed (n = 40; Spearman correlation r = 0.1140, p = 0.4836). (E) Correlation between head velocity and mean Z-scores during trace intervals where freezing was not observed (n = 10; Spearman correlation r = -0.1890, p = 0.6008). Solid lines and shades indicate linear regression and its 95% confidence intervals, respectively, for (D), (E).