a, Average traces for EPSCs recorded to determine PPR, rectification index (RI) and AMPAR/NMDAR ratio without pharmacological isolation. Ex vivo measurement of the PPR, rectification index and AMPAR/NMDAR ratio after in vivo stimulation of OFC–striatum terminals at 20 Hz for 1 min in renouncing mice (for PPR: control versus 20 Hz, two-sided t-test: t45 = 0.48, P = 0.63, n = 29 and 18 cells, respectively; for rectification index: control versus 20 Hz: t53 = 0.90, P = 0.37, n = 32 and 23 cells respectively; for AMPAR/NMDAR ratio: control versus 20 Hz: t58 = 6.79, *P < 0.0001, n = 32 and 28 cells, respectively). b, Effect of 20-Hz stimulation of OFC–striatum prior to a baseline session (n = 8 mice). Delay to engage the next action was not changed (ANOVA followed by two-sided t-test: *P < 0.05 when comparing control and 20 Hz). oDASS rate was not modified by 20 Hz stimulation before a baseline session (t7 = 0.97, P = 0.36, n = 8 mice for control versus 20 Hz before a baseline session). Data are mean ± s.e.m. See Supplementary Table 1 for complete statistics.