Miller Thomas H, Clements Katie, Ahn Sungwoo, Park Choongseok, Hye Ji Eoon, Issa Fadi A
Departments of Biology and.
Mathematics, East Carolina University, Greenville, North Carolina 27858.
J Neurosci. 2017 Feb 22;37(8):2137-2148. doi: 10.1523/JNEUROSCI.1548-16.2017. Epub 2017 Jan 16.
In a social group, animals make behavioral decisions that fit their social ranks. These behavioral choices are dependent on the various social cues experienced during social interactions. In vertebrates, little is known of how social status affects the underlying neural mechanisms regulating decision-making circuits that drive competing behaviors. Here, we demonstrate that social status in zebrafish () influences behavioral decisions by shifting the balance in neural circuit activation between two competing networks (escape and swim). We show that socially dominant animals enhance activation of the swim circuit. Conversely, social subordinates display a decreased activation of the swim circuit, but an enhanced activation of the escape circuit. In an effort to understand how social status mediates these effects, we constructed a neurocomputational model of the escape and swim circuits. The model replicates our findings and suggests that social status-related shift in circuit dynamics could be mediated by changes in the relative excitability of the escape and swim networks. Together, our results reveal that changes in the excitabilities of the Mauthner command neuron for escape and the inhibitory interneurons that regulate swimming provide a cellular mechanism for the nervous system to adapt to changes in social conditions by permitting the animal to select a socially appropriate behavioral response. Understanding how social factors influence nervous system function is of great importance. Using zebrafish as a model system, we demonstrate how social experience affects decision making to enable animals to produce socially appropriate behavior. Based on experimental evidence and computational modeling, we show that behavioral decisions reflect the interplay between competing neural circuits whose activation thresholds shift in accordance with social status. We demonstrate this through analysis of the behavior and neural circuit responses that drive escape and swim behaviors in fish. We show that socially subordinate animals favor escape over swimming, while socially dominants favor swimming over escape. We propose that these differences are mediated by shifts in relative circuit excitability.
在一个社会群体中，动物会做出符合其社会等级的行为决策。这些行为选择取决于社交互动过程中所经历的各种社会线索。在脊椎动物中，关于社会地位如何影响调节驱动竞争行为的决策回路的潜在神经机制，我们知之甚少。在这里，我们证明斑马鱼的社会地位通过改变两个竞争网络（逃避和游泳）之间神经回路激活的平衡来影响行为决策。我们发现，社会地位较高的动物增强了游泳回路的激活。相反，社会地位较低的动物游泳回路的激活减少，但逃避回路的激活增强。为了理解社会地位如何介导这些影响，我们构建了逃避和游泳回路的神经计算模型。该模型复制了我们的研究结果，并表明回路动力学中与社会地位相关的转变可能由逃避和游泳网络相对兴奋性的变化介导。总之，我们的结果表明，用于逃避的莫氏命令神经元和调节游泳的抑制性中间神经元兴奋性的变化为神经系统提供了一种细胞机制，使其能够通过允许动物选择符合社会情境的行为反应来适应社会条件的变化。理解社会因素如何影响神经系统功能非常重要。以斑马鱼为模型系统，我们展示了社会经验如何影响决策，使动物能够产生符合社会情境的行为。基于实验证据和计算建模，我们表明行为决策反映了竞争神经回路之间的相互作用，其激活阈值会根据社会地位而变化。我们通过分析驱动鱼类逃避和游泳行为的行为和神经回路反应来证明这一点。我们发现，社会地位较低的动物比起游泳更喜欢逃避，而社会地位较高的动物比起逃避更喜欢游泳。我们提出这些差异是由相对回路兴奋性的变化介导的。
