Context-dependent modulation of natural approach behavior in mice

Specific features of visual objects innately draw approach responses in animals, and provide natural signals of potential reward. However, visual sampling behaviors and the detection of salient, rewarding stimuli are context and behavioral state-dependent. The neural mechanisms underlying how the brain encodes naturally appetitive stimuli and conditionally transforms them into approach behavior remain unclear. To mechanistically understand this process, we probed natural approach behavior in mice by employing a virtual stimulus orienting paradigm based on prey capture to quantify the conditional expression of visual stimulus-evoked innate approach in freely moving mice. We found that specific combinations of stimulus features selectively evoked innate approach versus freezing behavioral responses when stimuli were unexpected. However, we discovered that prey capture experience, and therefore the expectation of prey in the environment, selectively modified a range of visually-evoked appe...视觉物体的特定特征天生可引发动物的趋近反应，并可作为潜在奖赏的自然信号。然而，视觉采样行为与显著性奖赏刺激的检测过程，均依赖于情境与行为状态。目前，大脑如何编码天然奖赏性刺激，并将其条件化转化为趋近行为的神经机制仍不明确。为从机制层面解析这一过程，我们采用基于猎物捕捉（prey capture）的虚拟刺激定向范式（virtual stimulus orienting paradigm），对自由活动小鼠的天然趋近行为进行探究，以量化视觉刺激诱发的先天趋近反应在自由活动小鼠中的条件性表达。我们发现，当刺激物处于意料之外的情境时，特定的刺激特征组合会选择性地引发先天趋近反应或僵滞行为反应。我们还发现，猎物捕捉经验及其所带来的环境中猎物存在的预期，会选择性地调控一系列视觉诱发的奖赏性（原文未完成）。