Figure 3. Hemodynamic responses to uncued rewards and penalties.

(A) Mean±SEM amount of liquids consumed when both were presented ad libitum simultaneously for 20 minutes in the animal's home enclosure on 3 days. No vinegar was consumed on any day. (B) Mean±SEM Peri-event changes in Δ[HbO], Δ[HbD], and Δ[HbTot] relative to baseline for unexpected delivery of 0.5mL of pleasant liquids (pomegranate juice or water) or unpleasant liquid (vinegar). Events delivered at pseudo-random intervals (min 40s). Asterisks indicate times at which the responses in pleasant and unpleasant trials were significantly different (Welchs t-test, p<0.05). (n = 121 rewards; n = 88 penalties).