The concept of prosocial behavior encompasses actions that promote the well-being of others, often motivated by emotional connections and empathy within a group. This behavior is also observed in non-human species, including rodents, frequently studied in neuroscience research. A previous study proposed the releasing of a trapped conspecific as a task to study prosocial behavior in laboratory rats. Nevertheless, the empathetic/prosocial motivation to liberate the trapped rat is controversial. In this study, we used a similar protocol to evaluate behavioral factors that may influence the performance of the conspecific release task (CRT). Adult female Wistar rats were submitted to the CRT conducted in an open field arena. An acrylic restrain box, in which a conspecific was trapped, was placed in the center of the arena. In Experiment 1, the rats were evaluated in six CRT trials, and the occurrence of the liberating behavior (opening trapping box) varied among subjects. We established a criterion for categorizing the opening behavior: the free rats that performed the CRT in 2 sessions or more were categorized into “opener” and the rats that performed the behavior one time, or never performed the CRT were categorized as “non-openers”. After separating the groups, behavioral parameters that possibly influenced CRT performance were compared between openers and non-openers. At the end of experiment 1, anxiety-like behavior was observed in animals belonging to the non-opener group, as expressed by diminished exploration of the center of the arena. In experiment 2 we applied pharmacological manipulation to modulate the anxiety-like behavior of the free rat, evaluating the effects of these variations on the liberating behavior. The rats that were categorized as non-openers were treated with the classical anxiolytic diazepam and the free rats categorized as openers received fluoxetine, that is anxiogenic when given acutely. Treatments were applied before the day of the test to evaluate performance in CRT. Non-openers treated with diazepam freed their cage mates, whereas openers treated with fluoxetine did not. The data suggests that anxiety-like levels influence CRT behavior.
KeywordsDistress RecognitionEmpathySocial BehaviorAnxietyDiazepam and Fluoxetine
Preston, S.D. and De Waal, F.B.M. (2002) The Communication of Emotions and the Possibility of Empathy in Animals. In: Altruism and Altruistic LoveScience , Philosophy , and Religion in Dialogue , Oxford University Press, 284-308. https://doi.org/10.1093/acprof:oso/9780195143584.003.0025
de Waal, F.B.M. (2008) Putting the Altruism Back into Altruism: The Evolution of Empathy. Annual Review of Psychology , 59, 279-300. https://doi.org/10.1146/annurev.psych.59.103006.093625
Batson, C.D., Eklund, J.H., Chermok, V.L., Hoyt, J.L. and Ortiz, B.G. (2007) An Additional Antecedent of Empathic Concern: Valuing the Welfare of the Person in Need. Journal of Personality and Social Psychology , 93, 65-74. https://doi.org/10.1037/0022-3514.93.1.65
Preston, S.D. and de Waal, F.B.M. (2002) Empathy: Its Ultimate and Proximate Bases. Behavioral and Brain Sciences , 25, 1-20. https://doi.org/10.1017/s0140525x02000018
Ben-Ami Bartal, I., Shan, H., Molasky, N.M.R., Murray, T.M., Williams, J.Z., Decety, J., et al. (2016) Anxiolytic Treatment Impairs Helping Behavior in Rats. Frontiers in Psychology , 7, Article ID: 850. https://doi.org/10.3389/fpsyg.2016.00850
de Waal, F.B.M. and Ferrari, P.F. (2011) The Primate Mind. Harvard University Press. https://doi.org/10.4159/harvard.9780674062917
Plutchik, R. (1990) Evolutionary Bases of Empathy. In: Eisenberg, N. and Strayer, J., Eds., Empathy and Its Development , University of Cambridge, 38-46.
Nowbahari, E., Scohier, A., Durand, J. and Hollis, K.L. (2009) Ants, Cataglyphis Cursor, Use Precisely Directed Rescue Behavior to Free Entrapped Relatives. PLOS ONE , 4, e6573. https://doi.org/10.1371/journal.pone.0006573
Luo, J. (2018) The Neural Basis of and a Common Neural Circuitry in Different Types of Pro-Social Behavior. Frontiers in Psychology , 9, Article ID: 859. https://doi.org/10.3389/fpsyg.2018.00859
Bartal, I.B., Decety, J. and Mason, P. (2011) Empathy and Pro-Social Behavior in Rats. Science , 334, 1427-1430. https://doi.org/10.1126/science.1210789
Sato, N., Tan, L., Tate, K. and Okada, M. (2015) Rats Demonstrate Helping Behavior toward a Soaked Conspecific. Animal Cognition , 18, 1039-1047. https://doi.org/10.1007/s10071-015-0872-2
Shima, T., Kawabata-Iwakawa, R., Onishi, H., Jesmin, S. and Yoshikawa, T. (2022) Four Weeks of Light-Intensity Exercise Enhances Empathic Behavior in Mice: The Possible Involvement of BDNF. Brain Research , 1787, Article 147920. https://doi.org/10.1016/j.brainres.2022.147920
Blystad, M.H. (2021) An Opinion on the Interpretation of Social Release in Rats. Biology Letters , 17, Article 20210355. https://doi.org/10.1098/rsbl.2021.0355
Marinho, G.F., Wuo, J.M., Kurita, J.P., Lima, A.C. and Silva, R.H. (2024) Motivational and Methodological Factors Involved in the Helping Behavior Test in Laboratory Rodents. Journal of Behavioral and Brain Science , 14, 240-254. https://doi.org/10.4236/jbbs.2024.148015
Silberberg, A., Allouch, C., Sandfort, S., Kearns, D., Karpel, H. and Slotnick, B. (2013) Desire for Social Contact, Not Empathy, May Explain “Rescue” Behavior in Rats. Animal Cognition , 17, 609-618. https://doi.org/10.1007/s10071-013-0692-1
Silva, A.F., Sousa, D.S., Medeiros, A.M., Macêdo, P.T., Leão, A.H., Ribeiro, A.M., et al. (2016) Sex and Estrous Cycle Influence Diazepam Effects on Anxiety and Memory: Possible Role of Progesterone. Progress in Neuro - Psychopharmacology and Biological Psychiatry , 70, 68-76. https://doi.org/10.1016/j.pnpbp.2016.05.003
Breton, J.M., Eisner, J.S., Gandhi, V.S., Musick, N., Zhang, A., Long, K.L.P., et al. (2022) Neural Activation Associated with Outgroup Helping in Adolescent Rats. iScience , 25, Article 104412. https://doi.org/10.1016/j.isci.2022.104412
Khalifeh, S., Khodagholi, F., Moghtadaei, M., Behvarmanesh, A., Kheradmand, A. and Ghazvini, H. (2019) Effects of Maternal Deprivation on Anxiety, Depression, and Empathy in Male and Female Offspring of Wistar Rats in the Face of Novel Objects. Galen Medical Journal , 8, e1093. https://doi.org/10.31661/gmj.v8i0.1093
Qu, Y., Zhang, L., An, S., Tai, F. and Qiao, H. (2023) Chronic Stress and Stressful Emotional Contagion Affect the Empathy-Like Behavior of Rats. Cognitive , Affective , & Behavioral Neuroscience , 23, 1160-1174. https://doi.org/10.3758/s13415-023-01081-9
Ketterer-Sykes, E.B., Saraceno, E., Hough, F., Wyse, M., Restifo-Bernstein, G., Blais, A.Y., et al. (2024) Anxiolytic Treatment of a Trapped Rat Reduces Helping and Anxiogenic Treatment Increases Helping: Evidence for Emotional Contagion in Altruism. Pharmacology Biochemistry and Behavior , 244, Article 173846. https://doi.org/10.1016/j.pbb.2024.173846
Yamagishi, A., Okada, M., Masuda, M. and Sato, N. (2020) Oxytocin Administration Modulates Rats’ Helping Behavior Depending on Social Context. Neuroscience Research , 153, 56-61. https://doi.org/10.1016/j.neures.2019.04.001
Kitano, K., Yamagishi, A., Horie, K., Nishimori, K. and Sato, N. (2022) Helping Behavior in Prairie Voles: A Model of Empathy and the Importance of Oxytocin. iScience , 25, Article 103991. https://doi.org/10.1016/j.isci.2022.103991
Mason, P. (2021) Lessons from Helping Behavior in Rats. Current Opinion in Neurobiology , 68, 52-56. https://doi.org/10.1016/j.conb.2021.01.001
Wu, W., Cheng, Y., Liang, K., Lee, R.X. and Yen, C. (2023) Affective Mirror and Anti-Mirror Neurons Relate to Prosocial Help in Rats. iScience , 26, Article 105865. https://doi.org/10.1016/j.isci.2022.105865
Treit, D. (1985) Evidence That Tolerance Develops to the Anxiolytic Effect of Diazepam in Rats. Pharmacology Biochemistry and Behavior , 22, 383-387. https://doi.org/10.1016/0091-3057(85)90036-x
Zienowicz, M., et al. (2006) Fluoxetine-Induced Anxiety and Nervousness. Pharmacological Reports , 58, 115-119.
Ben-Ami Bartal, I., Breton, J.M., Sheng, H., Long, K.L., Chen, S., Halliday, A., et al. (2021) Neural Correlates of Ingroup Bias for Prosociality in Rats. eLife , 10, e65582. https://doi.org/10.7554/elife.65582
Frommlet, F. (2020) Improving Reproducibility in Animal Research. Scientific Reports , 10, Article No. 19239. https://doi.org/10.1038/s41598-020-76398-3
Voelkl, B., Altman, N.S., Forsman, A., Forstmeier, W., Gurevitch, J., Jaric, I., et al. (2020) Reproducibility of Animal Research in Light of Biological Variation. Nature Reviews Neuroscience , 21, 384-393. https://doi.org/10.1038/s41583-020-0313-3
La-Vu, M., Tobias, B.C., Schuette, P.J. and Adhikari, A. (2020) To Approach or Avoid: An Introductory Overview of the Study of Anxiety Using Rodent Assays. Frontiers in Behavioral Neuroscience , 14, Article ID: 145. https://doi.org/10.3389/fnbeh.2020.00145
Seibenhener, M.L. and Wooten, M.C. (2015) Use of the Open Field Maze to Measure Locomotor and Anxiety-Like Behavior in Mice. Journal of Visualized Experiments , No. 96, e52434. https://doi.org/10.3791/52434-v
Kuniishi, H., Ichisaka, S., Yamamoto, M., Ikubo, N., Matsuda, S., Futora, E., et al. (2017) Early Deprivation Increases High-Leaning Behavior, a Novel Anxiety-Like Behavior, in the Open Field Test in Rats. Neuroscience Research , 123, 27-35. https://doi.org/10.1016/j.neures.2017.04.012
Belovicova, K., Bogi, E., Csatlosova, K. and Dubovicky, M. (2017) Animal Tests for Anxiety-Like and Depression-Like Behavior in Rats. Interdisciplinary Toxicology , 10, 40-43. https://doi.org/10.1515/intox-2017-0006
Kraeuter, A., Guest, P.C. and Sarnyai, Z. (2019) The Open Field Test for Measuring Locomotor Activity and Anxiety-Like Behavior. In: Guest, P., Ed., Methods in Molecular Biology , Springer, 99-103. https://doi.org/10.1007/978-1-4939-8994-2_9
Fontes-Dutra, M., Della-Flora Nunes, G., Santos-Terra, J., Souza-Nunes, W., Bauer-Negrini, G., Hirsch, M.M., et al. (2019) Abnormal Empathy-Like Pro-Social Behaviour in the Valproic Acid Model of Autism Spectrum Disorder. Behavioural Brain Research , 364, 11-18. https://doi.org/10.1016/j.bbr.2019.01.034
Tunçak, S., Gören, B., Uzbay, T. and Öz, P. (2025) Assessment of Empathy‐Like Behaviour in Valproic Acid-Induced Rat Model of Autism. International Journal of Developmental Neuroscience , 85, e70008. https://doi.org/10.1002/jdn.70008
Pozo, M., Milà-Guasch, M., Haddad-Tóvolli, R., Boudjadja, M.B., Chivite, I., Toledo, M., et al. (2023) Negative Energy Balance Hinders Prosocial Helping Behavior. Proceedings of the National Academy of Sciences , 120, e2218142120. https://doi.org/10.1073/pnas.2218142120
Bert, B., Fink, H., Sohr, R. and Rex, A. (2001) Different Effects of Diazepam in Fischer Rats and Two Stocks of Wistar Rats in Tests of Anxiety. Pharmacology Biochemistry and Behavior , 70, 411-420. https://doi.org/10.1016/s0091-3057(01)00629-3
Leão, A.H.F.F., Cabral, A., Izídio, G.S., Ribeiro, A.M. and Silva, R.H. (2016) Diazepam Effects on Aversive Memory Retrieval and Extinction: Role of Anxiety Levels. Pharmacology Biochemistry and Behavior , 141, 42-49. https://doi.org/10.1016/j.pbb.2015.11.012
Drapier, D., Bentueferrer, D., Laviolle, B., Millet, B., Allain, H., Bourin, M., et al. (2007) Effects of Acute Fluoxetine, Paroxetine and Desipramine on Rats Tested on the Elevated Plus-Maze. Behavioural Brain Research , 176, 202-209. https://doi.org/10.1016/j.bbr.2006.10.002
Grieb, Z.A., Voisin, D.A., Terranova, J.I., Norvelle, A., Michopoulos, V., Huhman, K.L., et al. (2022) Acute Administration of Fluoxetine Increases Social Avoidance and Risk Assessment Behaviors in a Sex-and Social Stress-Dependent Manner in Syrian Hamsters ( Mesocricetus auratus ). Pharmacology Biochemistry and Behavior , 214, Article 173353. https://doi.org/10.1016/j.pbb.2022.173353
Homberg, J.R., Schiepers, O.J.G., Schoffelmeer, A.N.M., Cuppen, E. and Vanderschuren, L.J.M.J. (2007) Acute and Constitutive Increases in Central Serotonin Levels Reduce Social Play Behaviour in Peri-Adolescent Rats. Psychopharmacology , 195, 175-182. https://doi.org/10.1007/s00213-007-0895-8
Salchner, P. and Singewald, N. (2002) Neuroanatomical Substrates Involved in the Anxiogenic-Like Effect of Acute Fluoxetine Treatment. Neuropharmacology , 43, 1238-1248. https://doi.org/10.1016/s0028-3908(02)00329-5
Robert, G., Drapier, D., Bentué-Ferrer, D., Renault, A. and Reymann, J. (2011) Acute and Chronic Anxiogenic-Like Response to Fluoxetine in Rats in the Elevated Plus-Maze: Modulation by Stressful Handling. Behavioural Brain Research , 220, 344-348. https://doi.org/10.1016/j.bbr.2011.01.051
Griebel, G., Cohen, C., Perrault, G. and Sanger, D.J. (1999) Behavioral Effects of Acute and Chronic Fluoxetine in Wistar-Kyoto Rats. Physiology & Behavior , 67, 315-320. https://doi.org/10.1016/s0031-9384(98)00298-4
Greenwood, B.N., Strong, P.V., Brooks, L. and Fleshner, M. (2008) Anxiety-Like Behaviors Produced by Acute Fluoxetine Administration in Male Fischer 344 Rats Are Prevented by Prior Exercise. Psychopharmacology , 199, 209-222. https://doi.org/10.1007/s00213-008-1167-y
Varty, G. (2002) The Gerbil Elevated Plus-Maze I Behavioral Characterization and Pharmacological Validation. Neuropsychopharmacology , 27, 357-370. https://doi.org/10.1016/s0893-133x(02)00312-3