Fig. 2. Fear conditioning induces bi-directional changes in BLA signaling.

(a) Percentages (± s.e.m.) of cells responding to the CS⁺, CS^–, or both stimuli.

(b) Ca²⁺ signals, showing changes in CS⁺ encoding and stable CS^– encoding for two sets of 125 cells detected throughout the study. Top, Cells responsive to the CS⁺ on at least one day. Bottom, Cells that either responded to the CS^– on one or more days, or lacked responses to both CS types. Colors show each cell’s Ca²⁺ response averaged over 5 CS presentations on the day the cell responded maximally, for days before and after fear conditioning (FC). Cells are arranged by whether they responded maximally before or after conditioning.

(c) Ca²⁺ signals from four cells, before (left, mean over 5 CS⁺ presentations), during (middle, single trial), and after (right, mean over 5 CS⁺ presentations) conditioning, illustrating altered responses to the CS⁺ (top two traces) or US (bottom two traces).

(d) Percentages (± s.e.m.) of cells after conditioning with stable, increased or decreased responses to the CS⁺ (red), CS^– (blue) and US (black), respectively based on 231, 362 and 261 neurons. Cells in the former two charts responded to the CS on at least one day before or after conditioning. Cells in the latter chart responded significantly to the US on Day 3.

Traces in b and c were down-sampled to 200 ms time bins. a, b, d are from N=12 mice.