Fontana Barbara D, Moraes Hevelyn S, Pretzel Camilla W, Mohammed Khadija A, Canzian Julia, Bonan Carla D, Parker Matthew O, Rosemberg Denis B
Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
Graduate Program in Biological Sciences: Toxicological Biochemistry, Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil.
Eur J Neurosci. 2025 Jul;62(1):e70173. doi: 10.1111/ejn.70173.
Individual differences in traits, such as boldness, significantly impact survival and adaptability by shaping responses to environmental challenges, including stress. Bolder individuals take greater risks to access resources and often display higher impulsivity, affecting behavioral domains like memory and cognition. Coping mechanisms in response to stressful situations may also differ between bold and shy individuals, with bold fish tending towards impulsive, less inhibited responses, whereas shy fish adopt cautious, controlled strategies. Despite these distinctions, the connections between boldness, stress reactivity, cognitive performance, and maladaptive behaviors remain poorly understood. Here, we used the zebrafish (Danio rerio) to examine these relationships. Boldness was assessed using the novel tank diving test, classifying fish as bold or shy based on overall and vertical exploratory activity. We then exposed fish to conspecific alarm substance (CAS), an acute naturalistic stressor, and assessed cognitive outcomes in the FMP Y-maze. Our results revealed distinct responses, with bold zebrafish showing poorer working memory performance and higher levels of repetitive behaviors following stress compared to shy fish, underscoring the impact of individual differences on stress reactivity and cognition. A positive correlation between boldness and repetitive behaviors was found for both control and CAS-exposed fish, indicating that boldness influences the escape strategies adopted by different phenotypes on the FMP Y-maze, especially in patterns associated with repetitive behaviors. These findings advance our understanding of how boldness influences stress responses and cognitive outcomes, providing a framework to examine resilience, impulsivity, and repetitive behaviors in translational neurobehavioral research.
诸如胆量等特质的个体差异，通过塑造对包括压力在内的环境挑战的反应，显著影响生存和适应性。胆子大的个体为获取资源会冒更大风险，且往往表现出更高的冲动性，影响记忆和认知等行为领域。在应对压力情境时，大胆和害羞的个体的应对机制也可能不同，大胆的鱼倾向于冲动、较少受抑制的反应，而害羞的鱼则采取谨慎、可控的策略。尽管存在这些差异，但胆量、应激反应性、认知表现和适应不良行为之间的联系仍知之甚少。在此，我们利用斑马鱼（Danio rerio）来研究这些关系。使用新鱼缸潜水测试评估胆量，根据总体和垂直探索活动将鱼分为大胆或害羞。然后，我们让鱼接触同种警报物质（CAS），一种急性自然应激源，并在FMP Y迷宫中评估认知结果。我们的结果显示出不同的反应，与害羞的鱼相比，大胆的斑马鱼在应激后工作记忆表现较差，重复行为水平较高，这突出了个体差异对应激反应性和认知的影响。在对照鱼和接触CAS的鱼中均发现胆量与重复行为之间存在正相关，表明胆量会影响不同表型在FMP Y迷宫中采取的逃避策略，尤其是与重复行为相关的模式。这些发现推进了我们对胆量如何影响应激反应和认知结果的理解，为在转化神经行为研究中研究恢复力、冲动性和重复行为提供了一个框架。
