An opinion on the interpretation of social release in rats

Abstract

This commentary concerns a controversial animal model in rodent social release research wherein one rat releases another rat from entrapment in a plastic tube. Release from the plastic tube has been proposed as a model to study empathically motivated behaviour. However, empathic motivations have been contested by others who have provided evidence for social reinforcement motivating release behaviour. Furthermore, helping, or other forms of pro-social behaviour could exist independent of empathy or empathetic motivation and the stimuli occasioning this helping behaviour are not known. In addition, there is a dearth in the citations of published studies whose results fail to support this model. In other words, the controversial aspect of the rodent social release model is often overlooked. This controversy is described in the current opinion piece.

No evidence tube entrapment distresses rodents in typical empathy tests

“…Subsequent work in which empathy and social-contact accounts have been compared has supported the primacy of a social process in explaining tube-based behavior (Hachiga et al 2018 ; Heslin and Brown 2021 ). As we and Blystad ( 2021 ) note, these results have generally not been addressed in reports favoring evidence for empathy as a motivating force using tube-based release behavior by free rats.…”

“…To date, few have acknowledged the importance of Kalamari et al ( 2021 ) anti-empathy finding or discussed the claims of Hachiga et al ( 2020 ). Blystad ( 2021 ) thinks this may be due to a citation bias among empathy researchers. Of course, there is a less self-serving explanation for why studies with incompatible results are not cited: perhaps investigators are unconvinced by Hachiga et al and Kalamari et al results or arguments.…”

Why help others? Insights from rodent to human early childhood research

“…Comparative research on these three species will promote a better understanding of the complex and dynamic developmental processes ( Lickliter and Bahrick, 2007 ) and clarify the roots of helping behavior. By summarizing the literature on rodent helping behavior, we found various explanations and debates surrounding the motivation for rodent helping behavior, such as altruism to empathize with others, egoism to alleviate their own distress, and the pursuit of social contact ( Bartal et al, 2011 , 2014 ; Schwartz et al, 2017 ; Carvalheiro et al, 2019 ; Blystad, 2021 ). This review aims to summarize and discuss the three types of helping behavior motivation from a cross-species perspective.…”

Spontaneous helping in pigs is mediated by helper's social attention and distress signals of individuals in need

“…Animal helping and human empathic responses share several trait features [10], including that both are mediated by the processing of social affective cues in similar brain regions (rodents: [11]; humans: [12]). Long-standing criticisms maintain that the available evidence is not sufficient to support empathy-like motivations underlying animal helping and that more parsimonious explanations are possible [13][14][15][16]. One major point of contention is about whether helping is truly goal-oriented, which would require showing not only that animals help in response to individuals in need, but also that observers modify helping appropriately when the target's needs change or when they no longer require help [17].…”

“…Moreover, some studies have assumed that their paradigms elicit distress without measuring responses of target individuals (e.g. [ 21 ]), leading others to question whether these individuals are even in need of help [ 14 , 16 , 18 ]. Interestingly, there is also evidence that high levels of distress by individuals in need may sometimes hinder helping [ 22 , 23 ].…”