Acute pain-related depression of operant responding maintained by social interaction or food in male and female rats

Effects of environmental manipulations on cocaine-vs-social choice in male and female rats

“…Second, in contrast to cocaine dose manipulations, experimental manipulations intended to alter the magnitude of social interaction as a reinforcer did not significantly alter cocaine-vs-social choice. These results were concordant with recent results demonstrating that social-access time was not a significant factor in operant responding for social interaction (Baldwin et al, 2022;Chow et al, 2022). Finally, non-contingent "sample" presentation of reinforcers before the discrete-choice trials did not significantly impact cocaine-vs-social choice.…”

“…Therefore, we hypothesized that increasing social-reinforcer magnitude by increasing the social-interaction time would increase social choice and decrease cocaine choice. However, there were no significant differences in behavioral allocation when social-interaction time was increased from 30 to 60 s. The present results are consistent with other recent results also showing that increasing social-interaction time from 30 to 60 s was ineffective to increase socialreinforcer magnitude (Baldwin et al, 2022;Chow et al, 2022). Results of prior studies suggest the opportunity for social "rough and tumble" play is more reinforcing than generalized social interaction, as evidenced by rats only showing conditioned place preference for a "partner" rat that can participate in play behavior (Calcagnetti and Schechter, 1992;Trezza et al, 2009).…”

“…Reduction of the social reinforcer magnitude by keeping the guillotine door closed and removal of the "Partner" rat failed to significantly increase cocaine choice. This result was unexpected, as failure to open the dividing guillotine door and partner rat removal had previously been shown to decrease responding when social access was the only reinforcer available (Baldwin et al, 2022). One potential explanation for the lack of robust effect of removing the social reinforcer is that association between the social stimulus light and social interaction with the "Partner" rat was not sufficiently extinguished over the five experimental days and longer extinction training might be required.…”

“…Since prior literature indicates that social interaction maintains lower levels of operant responding relative to food reinforcers (Baldwin et al, 2022;Chow et al, 2022), the ratio requirement on the social lever was held constant at FR3 during all trials to facilitate maintenance of social responding. If a rat failed to complete a ratio requirement within the 10min trial period, the trial terminated, a 30-s time out period ensued, the trial was counted as an omission, and the ratio requirement did not increment for the next trial.…”

Effects of environmental manipulations on cocaine-vs-social choice in male and female rats

“…The procedure consisted of nine choice trials to permit high response requirements that captured the cocaine breakpoint. Since prior literature indicates that social interaction maintains lower levels of operant responding relative to food reinforcers (Baldwin et al, 2022; Chow et al, 2022), the ratio requirement on the social lever was held constant at FR3 during all trials to facilitate maintenance of social responding. If a rat failed to complete a ratio requirement within the 10-min trial period, the trial terminated, a 30-s time out period ensued, the trial was counted as an omission, and the ratio requirement did not increment for the next trial.…”