Ferrara Nicole C, Trask Sydney, Ritger Alexandra, Padival Mallika, Rosenkranz J Amiel
Department of Foundational Sciences and Humanities, Discipline of Cellular and Molecular Pharmacology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States.
Center for Neurobiology of Stress Resilience and Psychiatric Disorders, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States.
Front Behav Neurosci. 2022 Aug 24;16:956102. doi: 10.3389/fnbeh.2022.956102. eCollection 2022.
Adolescence is a developmental period characterized by brain maturation and changes in social engagement. Changes in the social environment influence social behaviors. Memories of social events, including remembering familiar individuals, require social engagement during encoding. Therefore, existing differences in adult and adolescent social repertoires and environmentally-driven changes in social behavior may impact novel partner preference, associated with social recognition. Several amygdala subregions are sensitive to the social environment and can influence social behavior, which is crucial for novelty preference. Amygdala neurons project to the septum and nucleus accumbens (NAc), which are linked to social engagement. Here, we investigated how the social environment impacts age-specific social behaviors during social encoding and its subsequent impact on partner preference. We then examined changes in amygdala-septal and -NAc circuits that accompany these changes. Brief isolation can drive social behavior in both adults and adolescents and was used to increase social engagement during encoding. We found that brief isolation facilitates social interaction in adolescents and adults, and analysis across time revealed that partner discrimination was intact in all groups, but there was a shift in preference within isolated and non-isolated groups. We found that this same isolation preferentially increases basal amygdala (BA) activity relative to other amygdala subregions in adults, but activity among amygdala subregions was similar in adolescents, even when considering conditions (no isolation, isolation). Further, we identify isolation-driven increases in BA-NAc and BA-septal circuits in both adults and adolescents. Together, these results provide evidence for changes in neuronal populations within amygdala subregions and their projections that are sensitive to the social environment that may influence the pattern of social interaction within briefly isolated groups during development.
青春期是一个以大脑成熟和社交参与变化为特征的发育阶段。社会环境的变化会影响社会行为。社会事件的记忆，包括记住熟悉的个体，在编码过程中需要社交参与。因此，成人和青少年社交技能的现有差异以及环境驱动的社会行为变化可能会影响与社会认知相关的新伴侣偏好。杏仁核的几个亚区域对社会环境敏感，并能影响社会行为，这对新奇偏好至关重要。杏仁核神经元投射到与社交参与相关的隔区和伏隔核（NAc）。在这里，我们研究了社会环境如何在社交编码过程中影响特定年龄的社会行为及其对伴侣偏好的后续影响。然后，我们检查了伴随这些变化的杏仁核-隔区和-NAc回路的变化。短暂隔离可以驱动成人和青少年的社会行为，并被用于增加编码过程中的社交参与。我们发现短暂隔离促进了青少年和成人的社交互动，并且跨时间分析表明所有组中的伴侣辨别能力都是完整的，但在隔离组和非隔离组中偏好发生了转变。我们发现，相对于其他杏仁核亚区域，这种相同的隔离在成人中优先增加基底杏仁核（BA）的活动，但在青少年中，即使考虑不同条件（无隔离、隔离），杏仁核亚区域之间的活动也是相似的。此外，我们确定了隔离驱动的成人和青少年BA-NAc和BA-隔区回路的增加。总之，这些结果为杏仁核亚区域内神经元群体及其投射的变化提供了证据，这些变化对社会环境敏感，可能会影响发育过程中短暂隔离群体内的社会互动模式。
