==============================================================================
POWER SIMULATION -- matched_current_d0_3
==============================================================================
model: behavior ~ stim + day + stim:day + (1|rat)   (success COUNT; day within-window)
observed groups: stim n=3, control n=3   nrep=120, alpha=0.05
ground truth: stim:day=+10.20/day, rat SD=2.92, residual SD=8.54, days=4

 true stim:day interaction = +10.20 (100% of observed)
  N/group  | per-animal power | LME power
  ------------------------------------------
  3        |  0.55            |  0.91  <- observed
  5        |  0.93            |  0.98
  8        |  1.00            |  1.00
  12       |  1.00            |  1.00
  16       |  1.00            |  1.00
  24       |  1.00            |  1.00

 true stim:day interaction = +5.10 (50% of observed)
  N/group  | per-animal power | LME power
  ------------------------------------------
  3        |  0.11            |  0.33  <- observed
  5        |  0.42            |  0.57
  8        |  0.67            |  0.76
  12       |  0.89            |  0.90
  16       |  0.97            |  0.97
  24       |  1.00            |  1.00

Read the per-animal column as the honest power. At the observed N this study
is typically underpowered; per-animal power reaches ~0.8 only at larger N.