Trial lecture title: Prosocial Behavior in Rodents: Beyond the Social-release Paradigm.
Ordinary opponents:
- First opponent: Professor Timothy Hackenberg, Reed College, Oregon, USA
- Second opponent: Associate Professor Eelke Snoeren, UiT The Arctic University of Norway
- Leader of the committee: Associate Professor: Torunn Lian, Department of Behavioral Science, OsloMet
Leader of the public defense is Professor Magne Arve Flaten, Department of Behavioral Science, OsloMet.
The main supervisor is Professor Espen Borgå Johansen, Department of Behavioral Science, OsloMet. The co-supervisor is Professor Per Holth, Department of Behavioral Science, OsloMet.
Thesis abstract
Animal models of behaviour have been used since ancient Greece, both to study anatomy and behaviour. Social behaviour has also been modelled in non-human animals, and these models are especially important for the field of social neuroscience, which attempts to understand the neural mechanisms of social behaviour.
One such animal model is the social release paradigm, which claimed to demonstrate empathy in rats via observations of prosocial behaviour. In this paradigm, a rat is trapped inside a plastic tube and another rat can release the trapped conspecific. Empathic distress in the free rat is suggested to be the reason why opening behaviour occurs.
However, this claim of empathy in rats has been contested as findings point to social reinforcement being the most important factor for social release. Additionally, the interpretation in terms of empathy rests on a challenged premise that entrapment causes distress in the trapped rat. If entrapment is not distressing, then release from entrapment cannot be categorised as empathic or prosocial.
A systematization of previous research
The thesis points out the lack of a behaviourally focused definition of empathy fitting for animal studies. This is addressed by a novel conceptualization of empathy based on basic principles of behaviour analysis.
A systematization of previous research using the three-term contingency, also borrowed from the field of behaviour analysis, illustrates that little is known regarding antecedent stimuli in the social release paradigm.
Until the discriminative stimuli for opening is thoroughly studied and analysed, it seems premature to conclude that empathic motivation underlies social release. The current work also demonstrates how increased experimental control allows for better understanding of what controls behaviour in the social release paradigm.
Current findings
Improvements to the experimental design are demonstrated in the first experimental study, and these address the lack of both baseline and training in the original social release study.
Current findings show that latency to open the restrainer is lower for food than for a cagemate in food deprived rats.
Additionally, the premise of aversiveness due to entrapment, fundamental to the suggested empathic motivation, is tested in a second experimental paper; results of both exploration and vocalizations indicate that entrapment is not aversive.
The main contribution of the present work, in addition to the empirical findings, is the novel conceptualization and definition of empathy usable for animal studies, and the suggestion of how to systematize and integrate previous findings to identify new areas for future research.
In total, the most important takeaway message from this thesis is that an approach that focuses on what can be observed, rather than inferred, is a necessity in studies of social animal behaviour.
