Fig. S1.

Propranolol stabilizes single-unit bursting in the mPFC after footshock stress. (A and B) Spontaneous bursting rates averaged across all neurons and normalized to the preconditioning baseline for each brain region and treatment group. Fear conditioning (blue vertical bar) induced an increase in average spontaneous bursting rate in PL neurons from vehicle-treated rats (A, black trace; Inset shows first 20-s postshock bin in vehicle- and propranolol-treated rats) that was mitigated by propranolol treatment (A, red trace). Inset graph reveals no drug-induced difference in PL bursting, unlike for day 1 firing rate; red bar indicates propranolol and white bar indicates vehicle. Conditioning also induced a postshock increase in spontaneous bursting in IL neurons from vehicle-treated rats (B, black trace; Inset shows first 20-s postshock bin comparing vehicle and drug) and produced an enduring suppression of this activity. Propranolol treatment (B, red trace) mitigated this effect. Injection (INJ) is denoted by green vertical bar; conditioning (tone-shock pairings) is denoted by blue vertical bar. Data collected during the injection and conditioning periods were not recorded. All values are means (±SEM in insets).