Adaptive communication between cell assemblies and “reader” neurons shapes flexible brain dynamics
Fig 1
Candidate cell assembly activations are closely followed by downstream spiking.
(a) Simultaneous high-density recordings in the bidirectionally connected medial prefrontal cortex and amygdala (n = 4 rats; 5 sessions each). (b) Left: number of candidate cell assemblies detected in the medial prefrontal cortex (box and whiskers: distribution quartiles; dots: individual sessions) and peer prediction of the activity of candidate assembly members from other members (hierarchical bootstrap estimate of the mean gain relative to shuffled data, see Materials and methods; ***p < 0.001, Wilcoxon rank sum test). Right: same for candidate cell assemblies detected in the amygdala. (c) Example activations of candidate medial prefrontal cortical assembly closely followed (10 ms–30 ms) by responses of an amygdalar neuron. Top: candidate cell assembly weights (colored circles: assembly members, black circles: nonmembers). Bottom left: examples of candidate assembly activation (curves: activation strength) followed by downstream spiking (rasters: prefrontal spikes within (green) and outside (gray) epochs of candidate assembly activation; orange rasters: amygdalar spikes). Right: mean firing rate of amygdalar neuron centered on all prefrontal candidate assembly activations (mean ± s.e.m.) Thick orange horizontal bar indicates significant responses (p < 0.05: Monte–Carlo bootstrap test; see Materials and methods). (d) Same as (c) for candidate amygdalar assembly and downstream prefrontal neuron. (e) Average downstream responses (z-scored firing rates) centered on candidate assembly activations, over all significant pairs (color plots), and averaged across pairs (color curves), compared with the average activity of the upstream candidate assembly. Left: candidate prefrontal assemblies and amygdalar downstream neurons. Right: candidate amygdalar assemblies and downstream prefrontal neurons. (f) Percentage of significant candidate assembly–reader pairs found in shuffled recordings vs. real data (box and whiskers: distribution quartiles; dots: individual sessions; ***p < 0.001, Wilcoxon signed-rank test). The data underlying this Figure can be found in https://doi.org/10.6080/K09W0CQP.