Cassandre Vielle

PhD. Student

Contact Information

Department of Biology
Concordia University (Loyola Campus)
7141 Sherbrooke St. W. H4B 1R6
Montreal, QC, Canada
Lab: SP434
(514) 848-2424 (ext. 4021)

Cassandre.vielle@mail.concordia.ca

Education

2024 – Present: PhD in Biology, Concordia University, Montreal, Canada
2018-2022: PhD in Neuroscience, Aix-Marseille University, France
2016-2018: MSc in Cognitive Neuroscience, Aix-Marseille University, France
2013-2016: BSc in Biology of Populations and Ecosystems, Aix-Marseille University, France

My Project

The feedback loop between altruism and social structure altruism in semi-natural Norway rats (Rattus norvegicus).

Background

Altruism – defined as an act that incurs an immediate cost to the actor while benefiting the recipient (Taborsky et al., 2016) – is a cornerstone of animal and human societies. From an evolutionary perspective, altruism is primarily favored by the mechanisms of kin selection (benefiting genetically related individuals) (Hamilton, 1964; Smith, 1964) and reciprocity (increasing the likelihood to receive help in return) (Taborsky et al., 2016; Trivers, 1971).

However, altruistic behaviors are not isolated acts; they are embedded in social systems, as demonstrated by numerous examples across taxa (Raihani, 2021; Rubenstein & Abbot, 2017). Understanding how social systems facilitate altruism—via mechanisms like kin selection and reciprocity—and how altruism, in turn, shapes these systems, is crucial for comprehending the evolution of altruism and its integration into social dynamics.

Social structure, a core component of social systems, is characterized by the nature and pattern of social relationships, emerging from repeated interactions among group members, including intraspecific communication (Kappeler, 2019). Various dimensions of social structure influence altruism in animals and humans. Cooperative altruism is promoted by friendship in humans (Silk, 2003) and social bonds in animals (Freidin et al., 2017). In return, altruism fosters friendship in humans (Tooby & Cosmides, 1996) and camaraderie in animals (Lahvis, 2017), possibly enhancing group tolerance and cohesion. Cooperative altruism can also arise from coercive mechanisms (Ågren et al., 2019; Engelhardt & Taborsky, 2020), such as harassment and punishment (Clutton-Brock & Parker, 1995; Stevens, 2004). In this case of enforcement, the cost for resisting coercion outweighs the cost of complying with the coercer’s demands (Engelhardt & Taborsky, 2020). Dominance relationships also shape helping, by altering the cost and benefits of altruistic cooperation. While dominants often receive more altruistic acts, they are also more likely to share food when the cost is low (Duque & Stevens, 2016; Gachomba et al., 2024; Kalishov et al., 2005; Massen et al., 2010). Food sharing grants them with prestige and the deference of subordinates (Kafashan et al., 2014; Zahavi, 2004), thereby maintaining or enhancing their dominance status.

Here, we propose the social structure hypothesis: social relationships regulate help-seeking communication, and this interaction modulates help given and altruistic benefits (i.e., kin selection and reciprocity). In turn, help given strengthens yields altruistic cooperative benefits, and both strengthen social interactions and communication, creating a feedback loop that sustains altruistic cooperation. The experimental investigation of this hypothesis project will shed light on the underlying mechanisms facilitating the emergence and maintenance of altruistic behaviors, with potential implications for broader studies of cooperation in both animal and human societies.

Field work/Lab work

The research will be conducted using available data from Norway rat resulting from various experiments whereby colonies of female rats were exposed to different paradigms of food donation and video-taped for months.

More to come…

 

Objectives

In this thesis, I aim to investigate whether social relationships – bonding, agonistic/coercive, and dominance relationships – regulate help-seeking communication and helping (i.e., food donations), in semi-natural Rattus norvegicus colonies. I will also assess whether helping yields altruistic benefits – kin selection and reciprocity – and strengthen social interactions as outlined by the social structure hypothesis. I have three objectives, each of which forms the focus of a separate chapter:

Chapter 1.      Test the effect of social relationships on help-seeking expression: I predict that help-seeking behavior is promoted by stronger social bonding and higher dominance rank. If rats cooperate by coercion, increased initiations of agonistic interactions should also promote help-seeking requests.

Chapter 2.      Assess the influence of social relationships and help-seeking communication on altruistic helping and benefits: I expect help-seeking communication increases the frequency of food donations. Higher social bonding should reduce the latency of food donations after requests, increase food donations, and promote reciprocal food donations. High dominance rank should similarly reduce latency and increase donations to dominant individuals, without fostering reciprocity. If rats cooperate by coercion, initiations of agonistic interactions should reduce the latency between requests from the coercer and subsequent food donations and increase the frequency of these food donations, without reciprocity. Finally, I expect food donations to be preferentially directed toward kin (yielding kin selection) or social partners who have previously donated food (yielding reciprocity). Kin selection and reciprocity should also reduce the latency between requests and food donations.

Chapter 3.      Evaluate the impact of altruism on social interactions and help-seeking communication: I predict that an increase in the frequency of food donations will enhance affiliative interactions and reduce agonistic interactions, among donor-recipient pairs and among colonies. Within dyads, these effects should be amplified by kin selection and reciprocity. Reciprocity should promote help-seeking from previous donors, while kin selection should favor help-seeking from kin.

 

Publications

  1. Vielle, C. (2025) Beyond the Illusion of Controlled Environments: How to Embrace Ecological Pertinence in Research? Eur J Neurosci. 2025 Jan;61(1):e16661. doi: 10.1111/ejn.16661. PMID: 39777969.

  2. Vielle*, C., Engelhardt, S.C., Weladji, R.B. (2024). The feedback loop between altruism and social structure in semi-natural Rattus norvegicus. 49th Annual Meeting of the Société Québécoise d’Étude Biologique du Comportement. 15-17 November, 2024, Montreal, Québec, Canada, (Poster Presentation).

  3. Vignal, L., Vielle, C., Williams, M., Maurice, N., Degoulet, M., & Baunez, C. (2024). Subthalamic high-frequency deep brain stimulation reduces addiction-like alcohol use and the possible negative influence of a peer presence. Psychopharmacology, 1-13. https://doi.org/10.1007/s00213-024-06532-w.
  4. Vielle C., Montanari C., Pelloux Y., Baunez C. (2021) Evidence for a vocal signature in the rat and its reinforcing effects: a key role for the subthalamic nucleus. Proc. R. Soc. B 288: 20212260. https://doi.org/10.1098/rspb.2021.22602.
  5. Vielle C., Vignal L., Tiran-Cappello A., Degoulet M., Maurice N., Brocard C., Pelletier F., Pelloux Y., Baunez C., (submitted) Peer’s presence reverses escalated cocaine intake in rats: Involvement of the subthalamic nucleus. https://doi.org/10.1101/2023.02.07.527550
  6. Vielle C.,Maurice N., Pelletier F., Pecchi E., Baunez C., (in preparation) The subthalamic nucleus is involved in social memory recognition in rats. https://doi.org/10.1101/2023.02.07.527559
  7. Tiran-Cappello A., Vielle C., Pelloux Y., Brocard C., Degoulet M., Baunez C., (in preparation) A glimpse at deep brain stimulation mechanisms using subthalamic nucleus optogenetic manipulations.
  8. Giorla E., Nordmann S.,Vielle C., Pelloux Y., Roux P., Protopopescu C., Manrique C., Davranche K., Montanari C., Giorgi L., Vilotitch A., Huguet P., Carrieri P., Baunez C., (2022) Peer presence and familiarity as key factors to reduce cocaine intakein both rats and Humans: an effect mediated by the Subthalamic Nucleus. Psychopharmacology. https://doi.org/10.1007/s00213-021-06033-0
  9. Lguensat, A., Montanari, C., Vielle, C., Bennis, M., Ba-M’hamed, S., Baunez, C., & Garcia, R. (2021). Repeated cocaine exposure prior to fear conditioning induces persistency of PTSD-like symptoms and enhancement of hippocampal and amygdala cell density in male rats. Brain Structure and Function, 226(7), 2219-2241. https://doi.org/10.1007/s00429-021-02320-w