Figure 6:

Operant responses/20 minutes on an FR1 schedule of reinforcement in rats pre-treated i.p. with saline (left bars) or 0.1 mg/kg oxytocin (OT, right bars). Rats had previously been tested for cooperative responses when playing iterated Prisoner’s Dilemma (IPD) or Stag hunt (SH) with a Stooge who follows a random response strategy (IPD-Random), Win-stay/Lose-shift (IPD-WSLS), or Tit-for-tat (IPD-TFT, SH-TFT). See Figure 1 for experimental details.