Joana Rita da Silva Carvalheiro - CIPsi, University of Minho
Title: Modulatory effects of an escape alternative in pro-social behaviour
Abstract:
Pro-social behaviour is known to occur in response to familiar rat’s distress, but the motivations underlying helping behaviour remain elusive. In this study, we adapted the experimental setting of Bartal et al. (2011) to a paradigm that seeks to identify the motivation behind helping behaviour by giving individuals a chance to pursue a self-benefit goal (escape from distress). Inspired in the Light-Dark box test, we added a dark compartment to the Bartal pro-social arena to allow the free rat to escape through a open door, while a cage-mate rat was trapped in a restrainer that could only be opened from the outside. With the present design, we aimed to explore the motivation behind pro-social behaviour giving rats the possibility to relieve their own distress by escaping to a dark compartment. We investigated also how the trapped rat’s behaviour influenced the pro-social behaviour. To test our hypothesis, 5 pairs of cage-mate male Wistar rats (PND 41-53) were tested in this arena. As a control, 4 pairs of cage-mate males were tested in the same arena but with the door to the dark area closed to eliminate the escaping possibility. Rats were video recorded in 12 sessions of 60 minutes. If the free rat failed to open the restrain door during the initial 40 minutes, the experimenter would open it in 45 degrees (not counted as door opening). Rats remained in the arena until the end of the session. The behaviour of both free and trapped rats was analysed by animal focal analysis.
Our results showed that in the group of rats with the possibility to escape, the pro-social behavior decreased significantly, when compared to rats that did not have the escape choice. The escape condition gives helper-rats an opportunity to escape, which seems to decrease their state of anxiety. This condition did not facilitate pro-social behavior, since animals showed greater latency to door opening. We observed that anxious affective state in the helper rat reduced pro-social behavior, whereas proactive/positive behavior seems to facilitate pro-social behavior in both conditions. Results also showed that the pro-social behavior of the free rat was not influenced by the distress of trapped rats. Furthermore, this distress also was not correlated with escaping choices of the free rat, suggesting that free rat’s behavior was not modulated by the stress of the trapped rat. Interestingly, positive/proactive the behavior of the trapped rat, such as exploratory behavior, was negatively correlated with the latency to door opening. In summary, the motivation underlying pro-social behavior was not the trapped rat’s distress, but its proactive behavior, such as restrainer exploration. This novel behavioral approach shed light on the importance of positive emotional states in pro-social behavior.
Title: Modulatory effects of an escape alternative in pro-social behaviour
Abstract:
Pro-social behaviour is known to occur in response to familiar rat’s distress, but the motivations underlying helping behaviour remain elusive. In this study, we adapted the experimental setting of Bartal et al. (2011) to a paradigm that seeks to identify the motivation behind helping behaviour by giving individuals a chance to pursue a self-benefit goal (escape from distress). Inspired in the Light-Dark box test, we added a dark compartment to the Bartal pro-social arena to allow the free rat to escape through a open door, while a cage-mate rat was trapped in a restrainer that could only be opened from the outside. With the present design, we aimed to explore the motivation behind pro-social behaviour giving rats the possibility to relieve their own distress by escaping to a dark compartment. We investigated also how the trapped rat’s behaviour influenced the pro-social behaviour. To test our hypothesis, 5 pairs of cage-mate male Wistar rats (PND 41-53) were tested in this arena. As a control, 4 pairs of cage-mate males were tested in the same arena but with the door to the dark area closed to eliminate the escaping possibility. Rats were video recorded in 12 sessions of 60 minutes. If the free rat failed to open the restrain door during the initial 40 minutes, the experimenter would open it in 45 degrees (not counted as door opening). Rats remained in the arena until the end of the session. The behaviour of both free and trapped rats was analysed by animal focal analysis.
Our results showed that in the group of rats with the possibility to escape, the pro-social behavior decreased significantly, when compared to rats that did not have the escape choice. The escape condition gives helper-rats an opportunity to escape, which seems to decrease their state of anxiety. This condition did not facilitate pro-social behavior, since animals showed greater latency to door opening. We observed that anxious affective state in the helper rat reduced pro-social behavior, whereas proactive/positive behavior seems to facilitate pro-social behavior in both conditions. Results also showed that the pro-social behavior of the free rat was not influenced by the distress of trapped rats. Furthermore, this distress also was not correlated with escaping choices of the free rat, suggesting that free rat’s behavior was not modulated by the stress of the trapped rat. Interestingly, positive/proactive the behavior of the trapped rat, such as exploratory behavior, was negatively correlated with the latency to door opening. In summary, the motivation underlying pro-social behavior was not the trapped rat’s distress, but its proactive behavior, such as restrainer exploration. This novel behavioral approach shed light on the importance of positive emotional states in pro-social behavior.